diff --git a/BUILD b/BUILD
index 1355c1b..d25a5db 100644
--- a/BUILD
+++ b/BUILD
@@ -43,7 +43,10 @@
 
 cc_library(
     name = "jni_inc",
-    hdrs = [":jni/jni.h", ":jni/jni_md.h"],
+    hdrs = [
+        ":jni/jni.h",
+        ":jni/jni_md.h",
+    ],
     includes = ["jni"],
 )
 
@@ -141,6 +144,64 @@
     ],
 )
 
+########################################################
+# WARNING: do not (transitively) depend on this target!
+########################################################
+cc_library(
+    name = "jni",
+    srcs = [
+        ":common_sources",
+        ":dec_sources",
+        ":enc_sources",
+        "//java/org/brotli/wrapper/common:jni_src",
+        "//java/org/brotli/wrapper/dec:jni_src",
+        "//java/org/brotli/wrapper/enc:jni_src",
+    ],
+    hdrs = [
+        ":common_headers",
+        ":dec_headers",
+        ":enc_headers",
+    ],
+    deps = [
+        ":brotli_inc",
+        ":jni_inc",
+    ],
+    alwayslink = 1,
+)
+
+########################################################
+# WARNING: do not (transitively) depend on this target!
+########################################################
+cc_library(
+    name = "jni_no_dictionary_data",
+    srcs = [
+        ":common_sources",
+        ":dec_sources",
+        ":enc_sources",
+        "//java/org/brotli/wrapper/common:jni_src",
+        "//java/org/brotli/wrapper/dec:jni_src",
+        "//java/org/brotli/wrapper/enc:jni_src",
+    ],
+    hdrs = [
+        ":common_headers",
+        ":dec_headers",
+        ":enc_headers",
+    ],
+    defines = [
+        "BROTLI_EXTERNAL_DICTIONARY_DATA=",
+    ],
+    deps = [
+        ":brotli_inc",
+        ":jni_inc",
+    ],
+    alwayslink = 1,
+)
+
+filegroup(
+    name = "dictionary",
+    srcs = ["c/common/dictionary.bin"],
+)
+
 load("@io_bazel_rules_go//go:def.bzl", "go_prefix")
 
 go_prefix("github.com/google/brotli")
diff --git a/java/org/brotli/dec/BUILD b/java/org/brotli/dec/BUILD
index e7499a9..32c5897 100755
--- a/java/org/brotli/dec/BUILD
+++ b/java/org/brotli/dec/BUILD
@@ -7,17 +7,20 @@
 
 java_library(
     name = "dec",
-    srcs = glob(["*.java"], exclude = ["*Test*.java"]),
+    srcs = glob(
+        ["*.java"],
+        exclude = ["*Test*.java"],
+    ),
 )
 
 java_library(
     name = "test_lib",
+    testonly = 1,
     srcs = glob(["*Test*.java"]),
     deps = [
         ":dec",
         "@junit_junit//jar",
     ],
-    testonly = 1,
 )
 
 java_test(
diff --git a/java/org/brotli/dec/pom.xml b/java/org/brotli/dec/pom.xml
index ac6172f..24b7aa1 100755
--- a/java/org/brotli/dec/pom.xml
+++ b/java/org/brotli/dec/pom.xml
@@ -27,16 +27,16 @@
         <artifactId>maven-compiler-plugin</artifactId>
         <configuration>
           <includes>
-            <include>**/dec/*.java</include>
+            <include>org/brotli/dec/*.java</include>
           </includes>
           <excludes>
             <exclude>**/*Test*.java</exclude>
           </excludes>
           <testIncludes>
-            <include>**/dec/*Test*.java</include>
+            <include>org/brotli/dec/*Test*.java</include>
           </testIncludes>
           <testExcludes>
-            <exclude>**/dec/SetDictionaryTest.java</exclude>
+            <exclude>org/brotli/dec/SetDictionaryTest.java</exclude>
           </testExcludes>
         </configuration>
       </plugin>
@@ -53,7 +53,7 @@
             </goals>
             <configuration>
               <includes>
-                <include>**/dec/*.java</include>
+                <include>org/brotli/dec/*.java</include>
               </includes>
               <excludes>
                 <exclude>**/*Test*.java</exclude>
diff --git a/java/org/brotli/integration/BUILD b/java/org/brotli/integration/BUILD
index 31a2be8..ac9bc2c 100755
--- a/java/org/brotli/integration/BUILD
+++ b/java/org/brotli/integration/BUILD
@@ -4,6 +4,10 @@
 java_library(
     name = "bundle_helper",
     srcs = ["BundleHelper.java"],
+    visibility = [
+        "//java/org/brotli/wrapper/dec:__pkg__",
+        "//java/org/brotli/wrapper/enc:__pkg__",
+    ],
 )
 
 java_library(
@@ -34,10 +38,26 @@
     name = "bundle_checker_fuzz_test",
     args = [
         "-s",
-        "java/org/brotli/integration/fuzz_data.zip"
+        "java/org/brotli/integration/fuzz_data.zip",
     ],
     data = ["fuzz_data.zip"],
     main_class = "org.brotli.integration.BundleChecker",
     use_testrunner = 0,
     runtime_deps = [":bundle_checker"],
 )
+
+filegroup(
+    name = "test_data",
+    srcs = ["test_data.zip"],
+    visibility = [
+        "//java/org/brotli/wrapper/dec:__pkg__",
+    ],
+)
+
+filegroup(
+    name = "test_corpus",
+    srcs = ["test_corpus.zip"],
+    visibility = [
+        "//java/org/brotli/wrapper/enc:__pkg__",
+    ],
+)
diff --git a/java/org/brotli/wrapper/common/BUILD b/java/org/brotli/wrapper/common/BUILD
new file mode 100755
index 0000000..8623272
--- /dev/null
+++ b/java/org/brotli/wrapper/common/BUILD
@@ -0,0 +1,65 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])  # MIT
+
+filegroup(
+    name = "jni_src",
+    srcs = ["common_jni.cc"],
+)
+
+#########################################
+# WARNING: do not depend on this target!
+#########################################
+java_library(
+    name = "common_no_dictionary_data",
+    srcs = glob(
+        ["*.java"],
+        exclude = ["*Test*.java"],
+    ),
+    deps = ["//:jni_no_dictionary_data"],
+)
+
+#########################################
+# WARNING: do not depend on this target!
+#########################################
+java_library(
+    name = "common",
+    srcs = glob(
+        ["*.java"],
+        exclude = ["*Test*.java"],
+    ),
+    deps = ["//:jni"],
+)
+
+java_test(
+    name = "SetZeroDictionaryTest",
+    size = "small",
+    srcs = ["SetZeroDictionaryTest.java"],
+    data = ["//:jni_no_dictionary_data"],  # Bazel JNI workaround
+    deps = [
+        ":common_no_dictionary_data",
+        "//java/org/brotli/wrapper/dec",
+        "@junit_junit//jar",
+    ],
+)
+
+filegroup(
+    name = "rfc_dictionary",
+    srcs = ["//:dictionary"],
+)
+
+java_test(
+    name = "SetRfcDictionaryTest",
+    size = "small",
+    srcs = ["SetRfcDictionaryTest.java"],
+    data = [
+        ":rfc_dictionary",
+        "//:jni_no_dictionary_data",  # Bazel JNI workaround
+    ],
+    jvm_flags = ["-DRFC_DICTIONARY=$(location :rfc_dictionary)"],
+    deps = [
+        ":common_no_dictionary_data",
+        "//java/org/brotli/wrapper/dec",
+        "@junit_junit//jar",
+    ],
+)
diff --git a/java/org/brotli/wrapper/common/BrotliCommon.java b/java/org/brotli/wrapper/common/BrotliCommon.java
new file mode 100755
index 0000000..9419e42
--- /dev/null
+++ b/java/org/brotli/wrapper/common/BrotliCommon.java
@@ -0,0 +1,130 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.common;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+
+/**
+ * JNI wrapper for brotli common.
+ */
+public class BrotliCommon {
+  public static final int RFC_DICTIONARY_SIZE = 122784;
+
+  /* 96cecd2ee7a666d5aa3627d74735b32a */
+  private static final byte[] RFC_DICTIONARY_MD5 = {
+    -106, -50, -51, 46, -25, -90, 102, -43, -86, 54, 39, -41, 71, 53, -77, 42
+  };
+
+  /* 72b41051cb61a9281ba3c4414c289da50d9a7640 */
+  private static final byte[] RFC_DICTIONARY_SHA_1 = {
+    114, -76, 16, 81, -53, 97, -87, 40, 27, -93, -60, 65, 76, 40, -99, -91, 13, -102, 118, 64
+  };
+
+  /* 20e42eb1b511c21806d4d227d07e5dd06877d8ce7b3a817f378f313653f35c70 */
+  private static final byte[] RFC_DICTIONARY_SHA_256 = {
+    32, -28, 46, -79, -75, 17, -62, 24, 6, -44, -46, 39, -48, 126, 93, -48,
+    104, 119, -40, -50, 123, 58, -127, 127, 55, -113, 49, 54, 83, -13, 92, 112
+  };
+
+  private static boolean isDictionaryDataSet;
+  private static final Object mutex = new Object();
+
+  /**
+   * Checks if the given checksum matches MD5 checksum of the RFC dictionary.
+   */
+  public static boolean checkDictionaryDataMd5(byte[] digest) {
+    return Arrays.equals(RFC_DICTIONARY_MD5, digest);
+  }
+
+  /**
+   * Checks if the given checksum matches SHA-1 checksum of the RFC dictionary.
+   */
+  public static boolean checkDictionaryDataSha1(byte[] digest) {
+    return Arrays.equals(RFC_DICTIONARY_SHA_1, digest);
+  }
+
+  /**
+   * Checks if the given checksum matches SHA-256 checksum of the RFC dictionary.
+   */
+  public static boolean checkDictionaryDataSha256(byte[] digest) {
+    return Arrays.equals(RFC_DICTIONARY_SHA_256, digest);
+  }
+
+  /**
+   * Copy bytes to a new direct ByteBuffer.
+   *
+   * Direct byte buffers are used to supply native code with large data chunks.
+   */
+  public static ByteBuffer makeNative(byte[] data) {
+    ByteBuffer result = ByteBuffer.allocateDirect(data.length);
+    result.put(data);
+    return result;
+  }
+
+  /**
+   * Copies data and sets it to be brotli dictionary.
+   */
+  public static void setDictionaryData(byte[] data) {
+    if (data.length != RFC_DICTIONARY_SIZE) {
+      throw new IllegalArgumentException("invalid dictionary size");
+    }
+    synchronized (mutex) {
+      if (isDictionaryDataSet) {
+        return;
+      }
+      setDictionaryData(makeNative(data));
+    }
+  }
+
+  /**
+   * Reads data and sets it to be brotli dictionary.
+   */
+  public static void setDictionaryData(InputStream src) throws IOException {
+    synchronized (mutex) {
+      if (isDictionaryDataSet) {
+        return;
+      }
+      ByteBuffer copy = ByteBuffer.allocateDirect(RFC_DICTIONARY_SIZE);
+      byte[] buffer = new byte[4096];
+      int readBytes;
+      while ((readBytes = src.read(buffer)) != -1) {
+        if (copy.remaining() < readBytes) {
+          throw new IllegalArgumentException("invalid dictionary size");
+        }
+        copy.put(buffer, 0, readBytes);
+      }
+      if (copy.remaining() != 0) {
+        throw new IllegalArgumentException("invalid dictionary size " + copy.remaining());
+      }
+      setDictionaryData(copy);
+    }
+  }
+
+  /**
+   * Sets data to be brotli dictionary.
+   */
+  public static void setDictionaryData(ByteBuffer data) {
+    if (!data.isDirect()) {
+      throw new IllegalArgumentException("direct byte buffer is expected");
+    }
+    if (data.capacity() != RFC_DICTIONARY_SIZE) {
+      throw new IllegalArgumentException("invalid dictionary size");
+    }
+    synchronized (mutex) {
+      if (isDictionaryDataSet) {
+        return;
+      }
+      if (!CommonJNI.nativeSetDictionaryData(data)) {
+        throw new RuntimeException("setting dictionary failed");
+      }
+      isDictionaryDataSet = true;
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/common/CommonJNI.java b/java/org/brotli/wrapper/common/CommonJNI.java
new file mode 100755
index 0000000..d662546
--- /dev/null
+++ b/java/org/brotli/wrapper/common/CommonJNI.java
@@ -0,0 +1,16 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.common;
+
+import java.nio.ByteBuffer;
+
+/**
+ * JNI wrapper for brotli common.
+ */
+class CommonJNI {
+  static native boolean nativeSetDictionaryData(ByteBuffer data);
+}
diff --git a/java/org/brotli/wrapper/common/SetRfcDictionaryTest.java b/java/org/brotli/wrapper/common/SetRfcDictionaryTest.java
new file mode 100755
index 0000000..8577800
--- /dev/null
+++ b/java/org/brotli/wrapper/common/SetRfcDictionaryTest.java
@@ -0,0 +1,102 @@
+/* Copyright 2015 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.common;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+import org.brotli.wrapper.dec.BrotliInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/**
+ * Tests for {@link BrotliCommon}.
+ */
+@RunWith(JUnit4.class)
+public class SetRfcDictionaryTest {
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni_Uno_Udictionary_Udata.so").getAbsolutePath());
+  }
+
+  @Test
+  public void testRfcDictionaryChecksums() throws IOException, NoSuchAlgorithmException {
+    FileInputStream dictionary = new FileInputStream(System.getProperty("RFC_DICTIONARY"));
+    byte[] data = new byte[BrotliCommon.RFC_DICTIONARY_SIZE + 1];
+    int offset = 0;
+    try {
+      int readBytes;
+      while ((readBytes = dictionary.read(data, offset, data.length - offset)) != -1) {
+        offset += readBytes;
+        if (offset > BrotliCommon.RFC_DICTIONARY_SIZE) {
+          break;
+        }
+      }
+    } finally {
+      dictionary.close();
+    }
+    if (offset != BrotliCommon.RFC_DICTIONARY_SIZE) {
+      fail("dictionary size mismatch");
+    }
+
+    MessageDigest md5 = MessageDigest.getInstance("MD5");
+    md5.update(data, 0, offset);
+    assertTrue(BrotliCommon.checkDictionaryDataMd5(md5.digest()));
+
+    MessageDigest sha1 = MessageDigest.getInstance("SHA-1");
+    sha1.update(data, 0, offset);
+    assertTrue(BrotliCommon.checkDictionaryDataSha1(sha1.digest()));
+
+    MessageDigest sha256 = MessageDigest.getInstance("SHA-256");
+    sha256.update(data, 0, offset);
+    assertTrue(BrotliCommon.checkDictionaryDataSha256(sha256.digest()));
+  }
+
+  @Test
+  public void testSetRfcDictionary() throws IOException {
+    /* "leftdatadataleft" encoded with dictionary words. */
+    byte[] data = {27, 15, 0, 0, 0, 0, -128, -29, -76, 13, 0, 0, 7, 91, 38, 49, 64, 2, 0, -32, 78,
+        27, 65, -128, 32, 80, 16, 36, 8, 6};
+    FileInputStream dictionary = new FileInputStream(System.getProperty("RFC_DICTIONARY"));
+    try {
+      BrotliCommon.setDictionaryData(dictionary);
+    } finally {
+      dictionary.close();
+    }
+
+    BrotliInputStream decoder = new BrotliInputStream(new ByteArrayInputStream(data));
+    byte[] output = new byte[17];
+    int offset = 0;
+    try {
+      int bytesRead;
+      while ((bytesRead = decoder.read(output, offset, 17 - offset)) != -1) {
+        offset += bytesRead;
+      }
+    } finally {
+      decoder.close();
+    }
+    assertEquals(16, offset);
+    byte[] expected = {
+      'l', 'e', 'f', 't',
+      'd', 'a', 't', 'a',
+      'd', 'a', 't', 'a',
+      'l', 'e', 'f', 't',
+      0
+    };
+    assertArrayEquals(expected, output);
+  }
+}
diff --git a/java/org/brotli/wrapper/common/SetZeroDictionaryTest.java b/java/org/brotli/wrapper/common/SetZeroDictionaryTest.java
new file mode 100755
index 0000000..9046e31
--- /dev/null
+++ b/java/org/brotli/wrapper/common/SetZeroDictionaryTest.java
@@ -0,0 +1,53 @@
+/* Copyright 2015 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.common;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+
+import org.brotli.wrapper.dec.BrotliInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/**
+ * Tests for {@link BrotliCommon}.
+ */
+@RunWith(JUnit4.class)
+public class SetZeroDictionaryTest {
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni_Uno_Udictionary_Udata.so").getAbsolutePath());
+  }
+
+  @Test
+  public void testZeroDictionary() throws IOException {
+    /* "leftdatadataleft" encoded with dictionary words. */
+    byte[] data = {27, 15, 0, 0, 0, 0, -128, -29, -76, 13, 0, 0, 7, 91, 38, 49, 64, 2, 0, -32, 78,
+        27, 65, -128, 32, 80, 16, 36, 8, 6};
+    byte[] dictionary = new byte[BrotliCommon.RFC_DICTIONARY_SIZE];
+    BrotliCommon.setDictionaryData(dictionary);
+
+    BrotliInputStream decoder = new BrotliInputStream(new ByteArrayInputStream(data));
+    byte[] output = new byte[17];
+    int offset = 0;
+    try {
+      int bytesRead;
+      while ((bytesRead = decoder.read(output, offset, 17 - offset)) != -1) {
+        offset += bytesRead;
+      }
+    } finally {
+      decoder.close();
+    }
+    assertEquals(16, offset);
+    assertArrayEquals(new byte[17], output);
+  }
+}
diff --git a/java/org/brotli/wrapper/common/common_jni.cc b/java/org/brotli/wrapper/common/common_jni.cc
new file mode 100755
index 0000000..2ea2ad8
--- /dev/null
+++ b/java/org/brotli/wrapper/common/common_jni.cc
@@ -0,0 +1,47 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+#include <jni.h>
+
+#include "../common/dictionary.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Set data to be brotli dictionary data.
+ *
+ * @param buffer direct ByteBuffer
+ * @returns false if dictionary data was already set; otherwise true
+ */
+JNIEXPORT jint JNICALL
+Java_org_brotli_wrapper_common_CommonJNI_nativeSetDictionaryData(
+    JNIEnv* env, jobject /*jobj*/, jobject buffer) {
+  jobject buffer_ref = env->NewGlobalRef(buffer);
+  if (!buffer_ref) {
+    return false;
+  }
+  uint8_t* data = static_cast<uint8_t*>(env->GetDirectBufferAddress(buffer));
+  if (!data) {
+    env->DeleteGlobalRef(buffer_ref);
+    return false;
+  }
+
+  BrotliSetDictionaryData(data);
+
+  const BrotliDictionary* dictionary = BrotliGetDictionary();
+  if (dictionary->data != data) {
+    env->DeleteGlobalRef(buffer_ref);
+  } else {
+    /* Don't release reference; it is an intended memory leak. */
+  }
+  return true;
+}
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/java/org/brotli/wrapper/dec/BUILD b/java/org/brotli/wrapper/dec/BUILD
new file mode 100755
index 0000000..58ab3d4
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/BUILD
@@ -0,0 +1,73 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])  # MIT
+
+filegroup(
+    name = "jni_src",
+    srcs = ["decoder_jni.cc"],
+)
+
+#########################################
+# WARNING: do not depend on this target!
+#########################################
+java_library(
+    name = "dec",
+    srcs = glob(
+        ["*.java"],
+        exclude = ["*Test*.java"],
+    ),
+    deps = ["//:jni"],
+)
+
+filegroup(
+    name = "test_bundle",
+    srcs = ["//java/org/brotli/integration:test_data"],
+)
+
+java_test(
+    name = "BrotliDecoderChannelTest",
+    size = "large",
+    srcs = ["BrotliDecoderChannelTest.java"],
+    data = [
+        ":test_bundle",
+        "//:jni",  # Bazel JNI workaround
+    ],
+    jvm_flags = ["-DTEST_BUNDLE=$(location :test_bundle)"],
+    deps = [
+        ":dec",
+        "//java/org/brotli/integration:bundle_helper",
+        "@junit_junit//jar",
+    ],
+)
+
+java_test(
+    name = "BrotliInputStreamTest",
+    size = "large",
+    srcs = ["BrotliInputStreamTest.java"],
+    data = [
+        ":test_bundle",
+        "//:jni",  # Bazel JNI workaround
+    ],
+    jvm_flags = ["-DTEST_BUNDLE=$(location :test_bundle)"],
+    deps = [
+        ":dec",
+        "//java/org/brotli/integration:bundle_helper",
+        "@junit_junit//jar",
+    ],
+)
+
+java_test(
+    name = "DecoderTest",
+    size = "large",
+    srcs = ["DecoderTest.java"],
+    data = [
+        ":test_bundle",
+        "//:jni",  # Bazel JNI workaround
+    ],
+    jvm_flags = ["-DTEST_BUNDLE=$(location :test_bundle)"],
+    deps = [
+        ":dec",
+        "//java/org/brotli/integration:bundle_helper",
+        "@junit_junit//jar",
+    ],
+)
diff --git a/java/org/brotli/wrapper/dec/BrotliDecoderChannel.java b/java/org/brotli/wrapper/dec/BrotliDecoderChannel.java
new file mode 100755
index 0000000..e7b4bdf
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/BrotliDecoderChannel.java
@@ -0,0 +1,74 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.dec;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.ClosedChannelException;
+import java.nio.channels.ReadableByteChannel;
+
+/**
+ * ReadableByteChannel that wraps native brotli decoder.
+ */
+public class BrotliDecoderChannel extends Decoder implements ReadableByteChannel {
+  /** The default internal buffer size used by the decoder. */
+  private static final int DEFAULT_BUFFER_SIZE = 16384;
+
+  private final Object mutex = new Object();
+
+  /**
+   * Creates a BrotliDecoderChannel.
+   *
+   * @param source underlying source
+   * @param bufferSize intermediate buffer size
+   * @param customDictionary initial LZ77 dictionary
+   */
+  public BrotliDecoderChannel(ReadableByteChannel source, int bufferSize,
+      ByteBuffer customDictionary) throws IOException {
+    super(source, bufferSize, customDictionary);
+  }
+
+  public BrotliDecoderChannel(ReadableByteChannel source, int bufferSize) throws IOException {
+    super(source, bufferSize, null);
+  }
+
+  public BrotliDecoderChannel(ReadableByteChannel source) throws IOException {
+    this(source, DEFAULT_BUFFER_SIZE);
+  }
+
+  @Override
+  public boolean isOpen() {
+    synchronized (mutex) {
+      return !closed;
+    }
+  }
+
+  @Override
+  public void close() throws IOException {
+    synchronized (mutex) {
+      super.close();
+    }
+  }
+
+  @Override
+  public int read(ByteBuffer dst) throws IOException {
+    synchronized (mutex) {
+      if (closed) {
+        throw new ClosedChannelException();
+      }
+      int result = 0;
+      while (dst.hasRemaining()) {
+        int outputSize = decode();
+        if (outputSize == -1) {
+          return result == 0 ? -1 : result;
+        }
+        result += consume(dst);
+      }
+      return result;
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/dec/BrotliDecoderChannelTest.java b/java/org/brotli/wrapper/dec/BrotliDecoderChannelTest.java
new file mode 100755
index 0000000..b6fc036
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/BrotliDecoderChannelTest.java
@@ -0,0 +1,89 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.dec;
+
+import static org.junit.Assert.assertEquals;
+
+import org.brotli.integration.BundleHelper;
+import java.io.ByteArrayInputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import java.util.List;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+import org.junit.runner.RunWith;
+import org.junit.runners.AllTests;
+
+/** Tests for {@link org.brotli.wrapper.dec.BrotliDecoderChannel}. */
+@RunWith(AllTests.class)
+public class BrotliDecoderChannelTest {
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni.so").getAbsolutePath());
+  }
+
+  static InputStream getBundle() throws IOException {
+    return new FileInputStream(System.getProperty("TEST_BUNDLE"));
+  }
+
+  /** Creates a test suite. */
+  public static TestSuite suite() throws IOException {
+    TestSuite suite = new TestSuite();
+    InputStream bundle = getBundle();
+    try {
+      List<String> entries = BundleHelper.listEntries(bundle);
+      for (String entry : entries) {
+        suite.addTest(new ChannelTestCase(entry));
+      }
+    } finally {
+      bundle.close();
+    }
+    return suite;
+  }
+
+  /** Test case with a unique name. */
+  static class ChannelTestCase extends TestCase {
+    final String entryName;
+    ChannelTestCase(String entryName) {
+      super("BrotliDecoderChannelTest." + entryName);
+      this.entryName = entryName;
+    }
+
+    @Override
+    protected void runTest() throws Throwable {
+      BrotliDecoderChannelTest.run(entryName);
+    }
+  }
+
+  private static void run(String entryName) throws Throwable {
+    InputStream bundle = getBundle();
+    byte[] compressed;
+    try {
+      compressed = BundleHelper.readEntry(bundle, entryName);
+    } finally {
+      bundle.close();
+    }
+    if (compressed == null) {
+      throw new RuntimeException("Can't read bundle entry: " + entryName);
+    }
+
+    ReadableByteChannel src = Channels.newChannel(new ByteArrayInputStream(compressed));
+    ReadableByteChannel decoder = new BrotliDecoderChannel(src);
+    long crc;
+    try {
+      crc = BundleHelper.fingerprintStream(Channels.newInputStream(decoder));
+    } finally {
+      decoder.close();
+    }
+    assertEquals(BundleHelper.getExpectedFingerprint(entryName), crc);
+  }
+}
diff --git a/java/org/brotli/wrapper/dec/BrotliInputStream.java b/java/org/brotli/wrapper/dec/BrotliInputStream.java
new file mode 100755
index 0000000..63da868
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/BrotliInputStream.java
@@ -0,0 +1,108 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.dec;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.nio.channels.Channels;
+
+/**
+ * InputStream that wraps native brotli decoder.
+ */
+public class BrotliInputStream extends InputStream {
+  /** The default internal buffer size used by the decoder. */
+  private static final int DEFAULT_BUFFER_SIZE = 16384;
+
+  private final Decoder decoder;
+
+  /**
+   * Creates a BrotliInputStream.
+   *
+   * @param source underlying source
+   * @param bufferSize intermediate buffer size
+   * @param customDictionary initial LZ77 dictionary
+   */
+  public BrotliInputStream(InputStream source, int bufferSize, ByteBuffer customDictionary)
+      throws IOException {
+    this.decoder = new Decoder(Channels.newChannel(source), bufferSize, customDictionary);
+  }
+
+  public BrotliInputStream(InputStream source, int bufferSize) throws IOException {
+    this.decoder = new Decoder(Channels.newChannel(source), bufferSize, null);
+  }
+
+  public BrotliInputStream(InputStream source) throws IOException {
+    this(source, DEFAULT_BUFFER_SIZE);
+  }
+
+  @Override
+  public void close() throws IOException {
+    decoder.close();
+  }
+
+  @Override
+  public int available() {
+    return (decoder.buffer != null) ? decoder.buffer.remaining() : 0;
+  }
+
+  @Override
+  public int read() throws IOException {
+    if (decoder.closed) {
+      throw new IOException("read after close");
+    }
+    if (decoder.decode() == -1) {
+      return -1;
+    }
+    return decoder.buffer.get() & 0xFF;
+  }
+
+  @Override
+  public int read(byte[] b) throws IOException {
+    return read(b, 0, b.length);
+  }
+
+  @Override
+  public int read(byte[] b, int off, int len) throws IOException {
+    if (decoder.closed) {
+      throw new IOException("read after close");
+    }
+    if (decoder.decode() == -1) {
+      return -1;
+    }
+    int result = 0;
+    while (len > 0) {
+      int limit = Math.min(len, decoder.buffer.remaining());
+      decoder.buffer.get(b, off, limit);
+      off += limit;
+      len -= limit;
+      result += limit;
+      if (decoder.decode() == -1) {
+        break;
+      }
+    }
+    return result;
+  }
+
+  @Override
+  public long skip(long n) throws IOException {
+    if (decoder.closed) {
+      throw new IOException("read after close");
+    }
+    long result = 0;
+    while (n > 0) {
+      if (decoder.decode() == -1) {
+        break;
+      }
+      int limit = (int) Math.min(n, (long) decoder.buffer.remaining());
+      decoder.discard(limit);
+      result += limit;
+      n -= limit;
+    }
+    return result;
+  }
+}
diff --git a/java/org/brotli/wrapper/dec/BrotliInputStreamTest.java b/java/org/brotli/wrapper/dec/BrotliInputStreamTest.java
new file mode 100755
index 0000000..aec26a0
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/BrotliInputStreamTest.java
@@ -0,0 +1,87 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.dec;
+
+import static org.junit.Assert.assertEquals;
+
+import org.brotli.integration.BundleHelper;
+import java.io.ByteArrayInputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+import org.junit.runner.RunWith;
+import org.junit.runners.AllTests;
+
+/** Tests for {@link org.brotli.wrapper.dec.BrotliInputStream}. */
+@RunWith(AllTests.class)
+public class BrotliInputStreamTest {
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni.so").getAbsolutePath());
+  }
+
+  static InputStream getBundle() throws IOException {
+    return new FileInputStream(System.getProperty("TEST_BUNDLE"));
+  }
+
+  /** Creates a test suite. */
+  public static TestSuite suite() throws IOException {
+    TestSuite suite = new TestSuite();
+    InputStream bundle = getBundle();
+    try {
+      List<String> entries = BundleHelper.listEntries(bundle);
+      for (String entry : entries) {
+        suite.addTest(new StreamTestCase(entry));
+      }
+    } finally {
+      bundle.close();
+    }
+    return suite;
+  }
+
+  /** Test case with a unique name. */
+  static class StreamTestCase extends TestCase {
+    final String entryName;
+    StreamTestCase(String entryName) {
+      super("BrotliInputStreamTest." + entryName);
+      this.entryName = entryName;
+    }
+
+    @Override
+    protected void runTest() throws Throwable {
+      BrotliInputStreamTest.run(entryName);
+    }
+  }
+
+  private static void run(String entryName) throws Throwable {
+    InputStream bundle = getBundle();
+    byte[] compressed;
+    try {
+      compressed = BundleHelper.readEntry(bundle, entryName);
+    } finally {
+      bundle.close();
+    }
+    if (compressed == null) {
+      throw new RuntimeException("Can't read bundle entry: " + entryName);
+    }
+
+    InputStream src = new ByteArrayInputStream(compressed);
+    InputStream decoder = new BrotliInputStream(src);
+    long crc;
+    try {
+      crc = BundleHelper.fingerprintStream(decoder);
+    } finally {
+      decoder.close();
+    }
+    assertEquals(BundleHelper.getExpectedFingerprint(entryName), crc);
+  }
+}
diff --git a/java/org/brotli/wrapper/dec/Decoder.java b/java/org/brotli/wrapper/dec/Decoder.java
new file mode 100755
index 0000000..366045f
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/Decoder.java
@@ -0,0 +1,160 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.dec;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.ReadableByteChannel;
+import java.util.ArrayList;
+
+/**
+ * Base class for InputStream / Channel implementations.
+ */
+class Decoder {
+  private final ReadableByteChannel source;
+  private final DecoderJNI.Wrapper decoder;
+  ByteBuffer buffer;
+  boolean closed;
+
+  /**
+   * Creates a Decoder wrapper.
+   *
+   * @param source underlying source
+   * @param inputBufferSize read buffer size
+   */
+  public Decoder(ReadableByteChannel source, int inputBufferSize, ByteBuffer customDictionary)
+      throws IOException {
+    if (inputBufferSize <= 0) {
+      throw new IllegalArgumentException("buffer size must be positive");
+    }
+    if (source == null) {
+      throw new NullPointerException("source can not be null");
+    }
+    this.source = source;
+    this.decoder = new DecoderJNI.Wrapper(inputBufferSize, customDictionary);
+  }
+
+  private void fail(String message) throws IOException {
+    try {
+      close();
+    } catch (IOException ex) {
+      /* Ignore */
+    }
+    throw new IOException(message);
+  }
+
+  /**
+   * Continue decoding.
+   *
+   * @return -1 if stream is finished, or number of bytes available in read buffer (> 0)
+   */
+  int decode() throws IOException {
+    while (true) {
+      if (buffer != null) {
+        if (!buffer.hasRemaining()) {
+          buffer = null;
+        } else {
+          return buffer.remaining();
+        }
+      }
+
+      switch (decoder.getStatus()) {
+        case DONE:
+          return -1;
+
+        case OK:
+          decoder.push(0);
+          break;
+
+        case NEEDS_MORE_INPUT:
+          ByteBuffer inputBuffer = decoder.getInputBuffer();
+          inputBuffer.clear();
+          int bytesRead = source.read(inputBuffer);
+          if (bytesRead == -1) {
+            fail("unexpected end of input");
+          }
+          decoder.push(bytesRead);
+          break;
+
+        case NEEDS_MORE_OUTPUT:
+          buffer = decoder.pull();
+          break;
+
+        default:
+          fail("corrupted input");
+      }
+    }
+  }
+
+  void discard(int length) {
+    buffer.position(buffer.position() + length);
+    if (!buffer.hasRemaining()) {
+      buffer = null;
+    }
+  }
+
+  int consume(ByteBuffer dst) {
+    ByteBuffer slice = buffer.slice();
+    int limit = Math.min(slice.remaining(), dst.remaining());
+    slice.limit(limit);
+    dst.put(slice);
+    discard(limit);
+    return limit;
+  }
+
+  void close() throws IOException {
+    if (closed) {
+      return;
+    }
+    closed = true;
+    decoder.destroy();
+    source.close();
+  }
+
+  /**
+   * Decodes the given data buffer.
+   */
+  public static byte[] decompress(byte[] data) throws IOException {
+    DecoderJNI.Wrapper decoder = new DecoderJNI.Wrapper(data.length, null);
+    ArrayList<byte[]> output = new ArrayList<byte[]>();
+    int totalOutputSize = 0;
+    try {
+      decoder.getInputBuffer().put(data);
+      decoder.push(data.length);
+      while (decoder.getStatus() != DecoderJNI.Status.DONE) {
+        switch (decoder.getStatus()) {
+          case OK:
+            decoder.push(0);
+            break;
+
+          case NEEDS_MORE_OUTPUT:
+            ByteBuffer buffer = decoder.pull();
+            byte[] chunk = new byte[buffer.remaining()];
+            buffer.get(chunk);
+            output.add(chunk);
+            totalOutputSize += chunk.length;
+            break;
+
+          default:
+            throw new IOException("corrupted input");
+        }
+      }
+    } finally {
+      decoder.destroy();
+    }
+    if (output.size() == 1) {
+      return output.get(0);
+    }
+    byte[] result = new byte[totalOutputSize];
+    int offset = 0;
+    for (byte[] chunk : output) {
+      System.arraycopy(chunk, 0, result, offset, chunk.length);
+      offset += chunk.length;
+    }
+    return result;
+  }
+}
diff --git a/java/org/brotli/wrapper/dec/DecoderJNI.java b/java/org/brotli/wrapper/dec/DecoderJNI.java
new file mode 100755
index 0000000..ffd3ce9
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/DecoderJNI.java
@@ -0,0 +1,117 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.dec;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+/**
+ * JNI wrapper for brotli decoder.
+ */
+class DecoderJNI {
+  private static native ByteBuffer nativeCreate(long[] context, ByteBuffer customDictionary);
+  private static native void nativePush(long[] context, int length);
+  private static native ByteBuffer nativePull(long[] context);
+  private static native void nativeDestroy(long[] context);
+
+  enum Status {
+    ERROR,
+    DONE,
+    NEEDS_MORE_INPUT,
+    NEEDS_MORE_OUTPUT,
+    OK
+  };
+
+  static class Wrapper {
+    private final long[] context = new long[2];
+    private final ByteBuffer inputBuffer;
+    private Status lastStatus = Status.NEEDS_MORE_INPUT;
+
+    Wrapper(int inputBufferSize, ByteBuffer customDictionary) throws IOException {
+      if (customDictionary != null && !customDictionary.isDirect()) {
+        throw new IllegalArgumentException("LZ77 dictionary must be direct ByteBuffer");
+      }
+      this.context[1] = inputBufferSize;
+      this.inputBuffer = nativeCreate(this.context, customDictionary);
+      if (this.context[0] == 0) {
+        throw new IOException("failed to initialize native brotli decoder");
+      }
+    }
+
+    void push(int length) {
+      if (length < 0) {
+        throw new IllegalArgumentException("negative block length");
+      }
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli decoder is already destroyed");
+      }
+      if (lastStatus != Status.NEEDS_MORE_INPUT && lastStatus != Status.OK) {
+        throw new IllegalStateException("pushing input to decoder in " + lastStatus + " state");
+      }
+      if (lastStatus == Status.OK && length != 0) {
+        throw new IllegalStateException("pushing input to decoder in OK state");
+      }
+      nativePush(context, length);
+      parseStatus();
+    }
+
+    private void parseStatus() {
+      long status = context[1];
+      if (status == 1) {
+        lastStatus = Status.DONE;
+      } else if (status == 2) {
+        lastStatus = Status.NEEDS_MORE_INPUT;
+      } else if (status == 3) {
+        lastStatus = Status.NEEDS_MORE_OUTPUT;
+      } else if (status == 4) {
+        lastStatus = Status.OK;
+      } else {
+        lastStatus = Status.ERROR;
+      }
+    }
+
+    Status getStatus() {
+      return lastStatus;
+    }
+
+    ByteBuffer getInputBuffer() {
+      return inputBuffer;
+    }
+
+    ByteBuffer pull() {
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli decoder is already destroyed");
+      }
+      if (lastStatus != Status.NEEDS_MORE_OUTPUT) {
+        throw new IllegalStateException("pulling output from decoder in " + lastStatus + " state");
+      }
+      ByteBuffer result = nativePull(context);
+      parseStatus();
+      return result;
+    }
+
+    /**
+     * Releases native resources.
+     */
+    void destroy() {
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli decoder is already destroyed");
+      }
+      nativeDestroy(context);
+      context[0] = 0;
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+      if (context[0] != 0) {
+        /* TODO: log resource leak? */
+        destroy();
+      }
+      super.finalize();
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/dec/DecoderTest.java b/java/org/brotli/wrapper/dec/DecoderTest.java
new file mode 100755
index 0000000..0a8970f
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/DecoderTest.java
@@ -0,0 +1,82 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.dec;
+
+import static org.junit.Assert.assertEquals;
+
+import org.brotli.integration.BundleHelper;
+import java.io.ByteArrayInputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+import org.junit.runner.RunWith;
+import org.junit.runners.AllTests;
+
+/** Tests for {@link org.brotli.wrapper.dec.Decoder}. */
+@RunWith(AllTests.class)
+public class DecoderTest {
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni.so").getAbsolutePath());
+  }
+
+  static InputStream getBundle() throws IOException {
+    return new FileInputStream(System.getProperty("TEST_BUNDLE"));
+  }
+
+  /** Creates a test suite. */
+  public static TestSuite suite() throws IOException {
+    TestSuite suite = new TestSuite();
+    InputStream bundle = getBundle();
+    try {
+      List<String> entries = BundleHelper.listEntries(bundle);
+      for (String entry : entries) {
+        suite.addTest(new DecoderTestCase(entry));
+      }
+    } finally {
+      bundle.close();
+    }
+    return suite;
+  }
+
+  /** Test case with a unique name. */
+  static class DecoderTestCase extends TestCase {
+    final String entryName;
+    DecoderTestCase(String entryName) {
+      super("DecoderTest." + entryName);
+      this.entryName = entryName;
+    }
+
+    @Override
+    protected void runTest() throws Throwable {
+      DecoderTest.run(entryName);
+    }
+  }
+
+  private static void run(String entryName) throws Throwable {
+    InputStream bundle = getBundle();
+    byte[] compressed;
+    try {
+      compressed = BundleHelper.readEntry(bundle, entryName);
+    } finally {
+      bundle.close();
+    }
+    if (compressed == null) {
+      throw new RuntimeException("Can't read bundle entry: " + entryName);
+    }
+
+    byte[] decompressed = Decoder.decompress(compressed);
+
+    long crc = BundleHelper.fingerprintStream(new ByteArrayInputStream(decompressed));
+    assertEquals(BundleHelper.getExpectedFingerprint(entryName), crc);
+  }
+}
diff --git a/java/org/brotli/wrapper/dec/decoder_jni.cc b/java/org/brotli/wrapper/dec/decoder_jni.cc
new file mode 100755
index 0000000..b06cb5d
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/decoder_jni.cc
@@ -0,0 +1,228 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+#include <jni.h>
+
+#include <new>
+
+#include <brotli/decode.h>
+
+namespace {
+/* A structure used to persist the decoder's state in between calls. */
+typedef struct DecoderHandle {
+  BrotliDecoderState* state;
+
+  jobject custom_dictionary_ref;
+
+  uint8_t* input_start;
+  size_t input_offset;
+  size_t input_length;
+} DecoderHandle;
+
+/* Obtain handle from opaque pointer. */
+DecoderHandle* getHandle(void* opaque) {
+  return static_cast<DecoderHandle*>(opaque);
+}
+
+}  /* namespace */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Creates a new Decoder.
+ *
+ * Cookie to address created decoder is stored in out_cookie. In case of failure
+ * cookie is 0.
+ *
+ * @param ctx {out_cookie, in_directBufferSize} tuple
+ * @returns direct ByteBuffer if directBufferSize is not 0; otherwise null
+ */
+JNIEXPORT jobject JNICALL
+Java_org_brotli_wrapper_dec_DecoderJNI_nativeCreate(
+    JNIEnv* env, jobject /*jobj*/, jlongArray ctx, jobject custom_dictionary) {
+  bool ok = true;
+  DecoderHandle* handle = nullptr;
+  jlong context[2];
+  env->GetLongArrayRegion(ctx, 0, 2, context);
+  size_t input_size = context[1];
+  context[0] = 0;
+  handle = new (std::nothrow) DecoderHandle();
+  ok = !!handle;
+
+  if (ok) {
+    handle->custom_dictionary_ref = nullptr;
+    handle->input_offset = 0;
+    handle->input_length = 0;
+    handle->input_start = nullptr;
+
+    if (input_size == 0) {
+      ok = false;
+    } else {
+      handle->input_start = new (std::nothrow) uint8_t[input_size];
+      ok = !!handle->input_start;
+    }
+  }
+
+  if (ok) {
+    handle->state = BrotliDecoderCreateInstance(nullptr, nullptr, nullptr);
+    ok = !!handle->state;
+  }
+
+  if (ok && !!custom_dictionary) {
+    handle->custom_dictionary_ref = env->NewGlobalRef(custom_dictionary);
+    if (!!handle->custom_dictionary_ref) {
+      uint8_t* custom_dictionary_address = static_cast<uint8_t*>(
+          env->GetDirectBufferAddress(handle->custom_dictionary_ref));
+      if (!!custom_dictionary_address) {
+        jlong capacity =
+            env->GetDirectBufferCapacity(handle->custom_dictionary_ref);
+        ok = (capacity > 0) && (capacity < (1 << 24));
+        if (ok) {
+          size_t custom_dictionary_size = static_cast<size_t>(capacity);
+          BrotliDecoderSetCustomDictionary(
+              handle->state, custom_dictionary_size, custom_dictionary_address);
+        }
+      } else {
+        ok = false;
+      }
+    } else {
+      ok = false;
+    }
+  }
+
+  if (ok) {
+    /* TODO: future versions (e.g. when 128-bit architecture comes)
+                     might require thread-safe cookie<->handle mapping. */
+    context[0] = reinterpret_cast<jlong>(handle);
+  } else if (!!handle) {
+    if (!!handle->custom_dictionary_ref) {
+      env->DeleteGlobalRef(handle->custom_dictionary_ref);
+    }
+    if (!!handle->input_start) delete[] handle->input_start;
+    delete handle;
+  }
+
+  env->SetLongArrayRegion(ctx, 0, 2, context);
+
+  if (!ok) {
+    return nullptr;
+  }
+
+  return env->NewDirectByteBuffer(handle->input_start, input_size);
+}
+
+/**
+ * Push data to decoder.
+ *
+ * status codes:
+ *  - 0 error happened
+ *  - 1 stream is finished, no more input / output expected
+ *  - 2 needs more input to process further
+ *  - 3 needs more output to process further
+ *  - 4 ok, can proceed further without additional input
+ *
+ * @param ctx {in_cookie, out_status} tuple
+ * @param input_length number of bytes provided in input or direct input;
+ *                     0 to process further previous input
+ */
+JNIEXPORT void JNICALL
+Java_org_brotli_wrapper_dec_DecoderJNI_nativePush(
+    JNIEnv* env, jobject /*jobj*/, jlongArray ctx, jint input_length) {
+  jlong context[2];
+  env->GetLongArrayRegion(ctx, 0, 2, context);
+  DecoderHandle* handle = getHandle(reinterpret_cast<void*>(context[0]));
+  context[1] = 0;  /* ERROR */
+  env->SetLongArrayRegion(ctx, 0, 2, context);
+
+  if (input_length != 0) {
+    /* Still have unconsumed data. Workflow is broken. */
+    if (handle->input_offset < handle->input_length) {
+      return;
+    }
+    handle->input_offset = 0;
+    handle->input_length = input_length;
+  }
+
+  /* Actual decompression. */
+  const uint8_t* in = handle->input_start + handle->input_offset;
+  size_t in_size = handle->input_length - handle->input_offset;
+  size_t out_size = 0;
+  BrotliDecoderResult status = BrotliDecoderDecompressStream(
+      handle->state, &in_size, &in, &out_size, nullptr, nullptr);
+  handle->input_offset = handle->input_length - in_size;
+  switch (status) {
+    case BROTLI_DECODER_RESULT_SUCCESS:
+      /* Bytes after stream end are not allowed. */
+      context[1] = (handle->input_offset == handle->input_length) ? 1 : 0;
+      break;
+
+    case BROTLI_DECODER_RESULT_NEEDS_MORE_INPUT:
+      context[1] = 2;
+      break;
+
+    case BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT:
+      context[1] = 3;
+      break;
+
+    default:
+      context[1] = 0;
+      break;
+  }
+  env->SetLongArrayRegion(ctx, 0, 2, context);
+}
+
+/**
+ * Pull decompressed data from decoder.
+ *
+ * @param ctx {in_cookie, out_status} tuple
+ * @returns direct ByteBuffer; all the produced data MUST be consumed before
+ *          any further invocation; null in case of error
+ */
+JNIEXPORT jobject JNICALL
+Java_org_brotli_wrapper_dec_DecoderJNI_nativePull(
+    JNIEnv* env, jobject /*jobj*/, jlongArray ctx) {
+  jlong context[2];
+  env->GetLongArrayRegion(ctx, 0, 2, context);
+  DecoderHandle* handle = getHandle(reinterpret_cast<void*>(context[0]));
+  size_t data_length = 0;
+  const uint8_t* data = BrotliDecoderTakeOutput(handle->state, &data_length);
+  if (BrotliDecoderHasMoreOutput(handle->state)) {
+    context[1] = 3;
+  } else if (BrotliDecoderIsFinished(handle->state)) {
+    /* Bytes after stream end are not allowed. */
+    context[1] = (handle->input_offset == handle->input_length) ? 1 : 0;
+  } else {
+    /* Can proceed, or more data is required? */
+    context[1] = (handle->input_offset == handle->input_length) ? 2 : 4;
+  }
+  env->SetLongArrayRegion(ctx, 0, 2, context);
+  return env->NewDirectByteBuffer(const_cast<uint8_t*>(data), data_length);
+}
+
+/**
+ * Releases all used resources.
+ *
+ * @param ctx {in_cookie} tuple
+ */
+JNIEXPORT void JNICALL
+Java_org_brotli_wrapper_dec_DecoderJNI_nativeDestroy(
+    JNIEnv* env, jobject /*jobj*/, jlongArray ctx) {
+  jlong context[2];
+  env->GetLongArrayRegion(ctx, 0, 2, context);
+  DecoderHandle* handle = getHandle(reinterpret_cast<void*>(context[0]));
+  BrotliDecoderDestroyInstance(handle->state);
+  if (!!handle->custom_dictionary_ref) {
+    env->DeleteGlobalRef(handle->custom_dictionary_ref);
+  }
+  delete[] handle->input_start;
+  delete handle;
+}
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/java/org/brotli/wrapper/enc/BUILD b/java/org/brotli/wrapper/enc/BUILD
new file mode 100755
index 0000000..2290ab4
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/BUILD
@@ -0,0 +1,98 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])  # MIT
+
+filegroup(
+    name = "jni_src",
+    srcs = ["encoder_jni.cc"],
+)
+
+#########################################
+# WARNING: do not depend on this target!
+#########################################
+java_library(
+    name = "enc",
+    srcs = glob(
+        ["*.java"],
+        exclude = ["*Test*.java"],
+    ),
+    deps = ["//:jni"],
+)
+
+filegroup(
+    name = "test_bundle",
+    srcs = ["//java/org/brotli/integration:test_corpus"],
+)
+
+java_test(
+    name = "BrotliEncoderChannelTest",
+    size = "large",
+    srcs = ["BrotliEncoderChannelTest.java"],
+    data = [
+        ":test_bundle",
+        "//:jni",  # Bazel JNI workaround
+    ],
+    jvm_flags = ["-DTEST_BUNDLE=$(location :test_bundle)"],
+    shard_count = 15,
+    deps = [
+        ":enc",
+        "//java/org/brotli/integration:bundle_helper",
+        "//java/org/brotli/wrapper/dec",
+        "@junit_junit//jar",
+    ],
+)
+
+java_test(
+    name = "BrotliOutputStreamTest",
+    size = "large",
+    srcs = ["BrotliOutputStreamTest.java"],
+    data = [
+        ":test_bundle",
+        "//:jni",  # Bazel JNI workaround
+    ],
+    jvm_flags = ["-DTEST_BUNDLE=$(location :test_bundle)"],
+    shard_count = 15,
+    deps = [
+        ":enc",
+        "//java/org/brotli/integration:bundle_helper",
+        "//java/org/brotli/wrapper/dec",
+        "@junit_junit//jar",
+    ],
+)
+
+java_test(
+    name = "EncoderTest",
+    size = "large",
+    srcs = ["EncoderTest.java"],
+    data = [
+        ":test_bundle",
+        "//:jni",  # Bazel JNI workaround
+    ],
+    jvm_flags = ["-DTEST_BUNDLE=$(location :test_bundle)"],
+    shard_count = 15,
+    deps = [
+        ":enc",
+        "//java/org/brotli/integration:bundle_helper",
+        "//java/org/brotli/wrapper/dec",
+        "@junit_junit//jar",
+    ],
+)
+
+java_test(
+    name = "UseCustomDictionaryTest",
+    size = "large",
+    srcs = ["UseCustomDictionaryTest.java"],
+    data = [
+        ":test_bundle",
+        "//:jni",  # Bazel JNI workaround
+    ],
+    jvm_flags = ["-DTEST_BUNDLE=$(location :test_bundle)"],
+    shard_count = 15,
+    deps = [
+        ":enc",
+        "//java/org/brotli/integration:bundle_helper",
+        "//java/org/brotli/wrapper/common",
+        "//java/org/brotli/wrapper/dec",
+        "@junit_junit//jar",
+    ],
+)
diff --git a/java/org/brotli/wrapper/enc/BrotliEncoderChannel.java b/java/org/brotli/wrapper/enc/BrotliEncoderChannel.java
new file mode 100755
index 0000000..95a8b20
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/BrotliEncoderChannel.java
@@ -0,0 +1,82 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.enc;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.ClosedChannelException;
+import java.nio.channels.WritableByteChannel;
+
+/**
+ * WritableByteChannel that wraps native brotli encoder.
+ */
+public class BrotliEncoderChannel extends Encoder implements WritableByteChannel {
+  /** The default internal buffer size used by the decoder. */
+  private static final int DEFAULT_BUFFER_SIZE = 16384;
+
+  private final Object mutex = new Object();
+
+  /**
+   * Creates a BrotliEncoderChannel.
+   *
+   * @param destination underlying destination
+   * @param params encoding settings
+   * @param bufferSize intermediate buffer size
+   * @param customDictionary initial LZ77 dictionary
+   */
+  public BrotliEncoderChannel(WritableByteChannel destination, Encoder.Parameters params,
+      int bufferSize, ByteBuffer customDictionary) throws IOException {
+    super(destination, params, bufferSize, customDictionary);
+  }
+
+  public BrotliEncoderChannel(WritableByteChannel destination, Encoder.Parameters params,
+      int bufferSize) throws IOException {
+    super(destination, params, bufferSize, null);
+  }
+
+  public BrotliEncoderChannel(WritableByteChannel destination, Encoder.Parameters params)
+      throws IOException {
+    this(destination, params, DEFAULT_BUFFER_SIZE);
+  }
+
+  public BrotliEncoderChannel(WritableByteChannel destination) throws IOException {
+    this(destination, new Encoder.Parameters());
+  }
+
+  @Override
+  public boolean isOpen() {
+    synchronized (mutex) {
+      return !closed;
+    }
+  }
+
+  @Override
+  public void close() throws IOException {
+    synchronized (mutex) {
+      super.close();
+    }
+  }
+
+  @Override
+  public int write(ByteBuffer src) throws IOException {
+    synchronized (mutex) {
+      if (closed) {
+        throw new ClosedChannelException();
+      }
+      int result = 0;
+      while (src.hasRemaining() && encode(EncoderJNI.Operation.PROCESS)) {
+        int limit = Math.min(src.remaining(), inputBuffer.remaining());
+        ByteBuffer slice = src.slice();
+        slice.limit(limit);
+        inputBuffer.put(slice);
+        result += limit;
+        src.position(src.position() + limit);
+      }
+      return result;
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/enc/BrotliEncoderChannelTest.java b/java/org/brotli/wrapper/enc/BrotliEncoderChannelTest.java
new file mode 100755
index 0000000..1ab7599
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/BrotliEncoderChannelTest.java
@@ -0,0 +1,122 @@
+package org.brotli.wrapper.enc;
+
+import static org.junit.Assert.assertEquals;
+
+import org.brotli.integration.BundleHelper;
+import org.brotli.wrapper.dec.BrotliInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.nio.channels.Channels;
+import java.nio.channels.WritableByteChannel;
+import java.util.List;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+import org.junit.runner.RunWith;
+import org.junit.runners.AllTests;
+
+/** Tests for {@link org.brotli.wrapper.enc.BrotliEncoderChannel}. */
+@RunWith(AllTests.class)
+public class BrotliEncoderChannelTest {
+
+  private enum TestMode {
+    WRITE_ALL,
+    WRITE_CHUNKS
+  }
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni.so").getAbsolutePath());
+  }
+
+  private static final int CHUNK_SIZE = 256;
+
+  static InputStream getBundle() throws IOException {
+    return new FileInputStream(System.getProperty("TEST_BUNDLE"));
+  }
+
+  /** Creates a test suite. */
+  public static TestSuite suite() throws IOException {
+    TestSuite suite = new TestSuite();
+    InputStream bundle = getBundle();
+    try {
+      List<String> entries = BundleHelper.listEntries(bundle);
+      for (String entry : entries) {
+        suite.addTest(new ChannleTestCase(entry, TestMode.WRITE_ALL));
+        suite.addTest(new ChannleTestCase(entry, TestMode.WRITE_CHUNKS));
+      }
+    } finally {
+      bundle.close();
+    }
+    return suite;
+  }
+
+  /** Test case with a unique name. */
+  static class ChannleTestCase extends TestCase {
+    final String entryName;
+    final TestMode mode;
+    ChannleTestCase(String entryName, TestMode mode) {
+      super("BrotliEncoderChannelTest." + entryName + "." + mode.name());
+      this.entryName = entryName;
+      this.mode = mode;
+    }
+
+    @Override
+    protected void runTest() throws Throwable {
+      BrotliEncoderChannelTest.run(entryName, mode);
+    }
+  }
+
+  private static void run(String entryName, TestMode mode) throws Throwable {
+    InputStream bundle = getBundle();
+    byte[] original;
+    try {
+      original = BundleHelper.readEntry(bundle, entryName);
+    } finally {
+      bundle.close();
+    }
+    if (original == null) {
+      throw new RuntimeException("Can't read bundle entry: " + entryName);
+    }
+
+    if ((mode == TestMode.WRITE_CHUNKS) && (original.length <= CHUNK_SIZE)) {
+      return;
+    }
+
+    ByteArrayOutputStream dst = new ByteArrayOutputStream();
+    WritableByteChannel encoder = new BrotliEncoderChannel(Channels.newChannel(dst));
+    ByteBuffer src = ByteBuffer.wrap(original);
+    try {
+      switch (mode) {
+        case WRITE_ALL:
+          encoder.write(src);
+          break;
+
+        case WRITE_CHUNKS:
+          while (src.hasRemaining()) {
+            int limit = Math.min(CHUNK_SIZE, src.remaining());
+            ByteBuffer slice = src.slice();
+            slice.limit(limit);
+            src.position(src.position() + limit);
+            encoder.write(slice);
+          }
+          break;
+      }
+    } finally {
+      encoder.close();
+    }
+
+    InputStream decoder = new BrotliInputStream(new ByteArrayInputStream(dst.toByteArray()));
+    try {
+      long originalCrc = BundleHelper.fingerprintStream(new ByteArrayInputStream(original));
+      long crc = BundleHelper.fingerprintStream(decoder);
+      assertEquals(originalCrc, crc);
+    } finally {
+      decoder.close();
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/enc/BrotliOutputStream.java b/java/org/brotli/wrapper/enc/BrotliOutputStream.java
new file mode 100755
index 0000000..1cee434
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/BrotliOutputStream.java
@@ -0,0 +1,95 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.enc;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+import java.nio.channels.Channels;
+
+/**
+ * Output stream that wraps native brotli encoder.
+ */
+public class BrotliOutputStream extends OutputStream {
+  /** The default internal buffer size used by the encoder. */
+  private static final int DEFAULT_BUFFER_SIZE = 16384;
+
+  private final Encoder encoder;
+
+  /**
+   * Creates a BrotliOutputStream.
+   *
+   * @param destination underlying destination
+   * @param params encoding settings
+   * @param bufferSize intermediate buffer size
+   * @param customDictionary initial LZ77 dictionary
+   */
+  public BrotliOutputStream(OutputStream destination, Encoder.Parameters params, int bufferSize,
+      ByteBuffer customDictionary) throws IOException {
+    this.encoder = new Encoder(
+        Channels.newChannel(destination), params, bufferSize, customDictionary);
+  }
+
+  public BrotliOutputStream(OutputStream destination, Encoder.Parameters params, int bufferSize)
+      throws IOException {
+    this.encoder = new Encoder(Channels.newChannel(destination), params, bufferSize, null);
+  }
+
+  public BrotliOutputStream(OutputStream destination, Encoder.Parameters params)
+      throws IOException {
+    this(destination, params, DEFAULT_BUFFER_SIZE);
+  }
+
+  public BrotliOutputStream(OutputStream destination) throws IOException {
+    this(destination, new Encoder.Parameters());
+  }
+
+  @Override
+  public void close() throws IOException {
+    encoder.close();
+  }
+
+  @Override
+  public void flush() throws IOException {
+    if (encoder.closed) {
+      throw new IOException("write after close");
+    }
+    encoder.flush();
+  }
+
+  @Override
+  public void write(int b) throws IOException {
+    if (encoder.closed) {
+      throw new IOException("write after close");
+    }
+    while (!encoder.encode(EncoderJNI.Operation.PROCESS)) {
+      // Busy-wait loop.
+    }
+    encoder.inputBuffer.put((byte) b);
+  }
+
+  @Override
+  public void write(byte[] b) throws IOException {
+    this.write(b, 0, b.length);
+  }
+
+  @Override
+  public void write(byte[] b, int off, int len) throws IOException {
+    if (encoder.closed) {
+      throw new IOException("write after close");
+    }
+    while (len > 0) {
+      if (!encoder.encode(EncoderJNI.Operation.PROCESS)) {
+        continue;
+      }
+      int limit = Math.min(len, encoder.inputBuffer.remaining());
+      encoder.inputBuffer.put(b, off, limit);
+      off += limit;
+      len -= limit;
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/enc/BrotliOutputStreamTest.java b/java/org/brotli/wrapper/enc/BrotliOutputStreamTest.java
new file mode 100755
index 0000000..a436e81
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/BrotliOutputStreamTest.java
@@ -0,0 +1,123 @@
+package org.brotli.wrapper.enc;
+
+import static org.junit.Assert.assertEquals;
+
+import org.brotli.integration.BundleHelper;
+import org.brotli.wrapper.dec.BrotliInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.List;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+import org.junit.runner.RunWith;
+import org.junit.runners.AllTests;
+
+/** Tests for {@link org.brotli.wrapper.enc.BrotliOutputStream}. */
+@RunWith(AllTests.class)
+public class BrotliOutputStreamTest {
+
+  private enum TestMode {
+    WRITE_ALL,
+    WRITE_CHUNKS,
+    WRITE_BYTE
+  }
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni.so").getAbsolutePath());
+  }
+
+  private static final int CHUNK_SIZE = 256;
+
+  static InputStream getBundle() throws IOException {
+    return new FileInputStream(System.getProperty("TEST_BUNDLE"));
+  }
+
+  /** Creates a test suite. */
+  public static TestSuite suite() throws IOException {
+    TestSuite suite = new TestSuite();
+    InputStream bundle = getBundle();
+    try {
+      List<String> entries = BundleHelper.listEntries(bundle);
+      for (String entry : entries) {
+        suite.addTest(new StreamTestCase(entry, TestMode.WRITE_ALL));
+        suite.addTest(new StreamTestCase(entry, TestMode.WRITE_CHUNKS));
+        suite.addTest(new StreamTestCase(entry, TestMode.WRITE_BYTE));
+      }
+    } finally {
+      bundle.close();
+    }
+    return suite;
+  }
+
+  /** Test case with a unique name. */
+  static class StreamTestCase extends TestCase {
+    final String entryName;
+    final TestMode mode;
+    StreamTestCase(String entryName, TestMode mode) {
+      super("BrotliOutputStreamTest." + entryName + "." + mode.name());
+      this.entryName = entryName;
+      this.mode = mode;
+    }
+
+    @Override
+    protected void runTest() throws Throwable {
+      BrotliOutputStreamTest.run(entryName, mode);
+    }
+  }
+
+  private static void run(String entryName, TestMode mode) throws Throwable {
+    InputStream bundle = getBundle();
+    byte[] original;
+    try {
+      original = BundleHelper.readEntry(bundle, entryName);
+    } finally {
+      bundle.close();
+    }
+    if (original == null) {
+      throw new RuntimeException("Can't read bundle entry: " + entryName);
+    }
+
+    if ((mode == TestMode.WRITE_CHUNKS) && (original.length <= CHUNK_SIZE)) {
+      return;
+    }
+
+    ByteArrayOutputStream dst = new ByteArrayOutputStream();
+    OutputStream encoder = new BrotliOutputStream(dst);
+    try {
+      switch (mode) {
+        case WRITE_ALL:
+          encoder.write(original);
+          break;
+
+        case WRITE_CHUNKS:
+          for (int offset = 0; offset < original.length; offset += CHUNK_SIZE) {
+            encoder.write(original, offset, Math.min(CHUNK_SIZE, original.length - offset));
+          }
+          break;
+
+        case WRITE_BYTE:
+          for (byte singleByte : original) {
+            encoder.write(singleByte);
+          }
+          break;
+      }
+    } finally {
+      encoder.close();
+    }
+
+    InputStream decoder = new BrotliInputStream(new ByteArrayInputStream(dst.toByteArray()));
+    try {
+      long originalCrc = BundleHelper.fingerprintStream(new ByteArrayInputStream(original));
+      long crc = BundleHelper.fingerprintStream(decoder);
+      assertEquals(originalCrc, crc);
+    } finally {
+      decoder.close();
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/enc/Encoder.java b/java/org/brotli/wrapper/enc/Encoder.java
new file mode 100755
index 0000000..55cc369
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/Encoder.java
@@ -0,0 +1,200 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.enc;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.WritableByteChannel;
+import java.util.ArrayList;
+
+/**
+ * Base class for OutputStream / Channel implementations.
+ */
+public class Encoder {
+  private final WritableByteChannel destination;
+  private final EncoderJNI.Wrapper encoder;
+  final ByteBuffer inputBuffer;
+  ByteBuffer buffer;
+  boolean closed;
+
+  /**
+   * Brotli encoder settings.
+   */
+  public static final class Parameters {
+    private int quality = -1;
+    private int lgwin = -1;
+
+    public Parameters() { }
+
+    private Parameters(Parameters other) {
+      this.quality = other.quality;
+      this.lgwin = other.lgwin;
+    }
+
+    /**
+     * @param quality compression quality, or -1 for default
+     */
+    public Parameters setQuality(int quality) {
+      if (quality < -1 || quality > 11) {
+        throw new IllegalArgumentException("quality should be in range [0, 11], or -1");
+      }
+      this.quality = quality;
+      return this;
+    }
+
+    /**
+     * @param lgwin log2(LZ window size), or -1 for default
+     */
+    public Parameters setWindow(int lgwin) {
+      if ((lgwin != -1) && ((lgwin < 10) || (lgwin > 24))) {
+        throw new IllegalArgumentException("lgwin should be in range [10, 24], or -1");
+      }
+      this.lgwin = lgwin;
+      return this;
+    }
+  }
+
+  /**
+   * Creates a Encoder wrapper.
+   *
+   * @param destination underlying destination
+   * @param params encoding parameters
+   * @param inputBufferSize read buffer size
+   */
+  Encoder(WritableByteChannel destination, Parameters params, int inputBufferSize,
+      ByteBuffer customDictionary) throws IOException {
+    if (inputBufferSize <= 0) {
+      throw new IllegalArgumentException("buffer size must be positive");
+    }
+    if (destination == null) {
+      throw new NullPointerException("destination can not be null");
+    }
+    this.destination = destination;
+    this.encoder = new EncoderJNI.Wrapper(
+        inputBufferSize, params.quality, params.lgwin, customDictionary);
+    this.inputBuffer = this.encoder.getInputBuffer();
+  }
+
+  private void fail(String message) throws IOException {
+    try {
+      close();
+    } catch (IOException ex) {
+      /* Ignore */
+    }
+    throw new IOException(message);
+  }
+
+  /**
+   * @param force repeat pushing until all output is consumed
+   * @return true if all encoder output is consumed
+   */
+  boolean pushOutput(boolean force) throws IOException {
+    while (buffer != null) {
+      if (buffer.hasRemaining()) {
+        destination.write(buffer);
+      }
+      if (!buffer.hasRemaining()) {
+        buffer = null;
+      } else if (!force) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  /**
+   * @return true if there is space in inputBuffer.
+   */
+  boolean encode(EncoderJNI.Operation op) throws IOException {
+    boolean force = (op != EncoderJNI.Operation.PROCESS);
+    if (force) {
+      inputBuffer.limit(inputBuffer.position());
+    } else if (inputBuffer.hasRemaining()) {
+      return true;
+    }
+    boolean hasInput = true;
+    while (true) {
+      if (!encoder.isSuccess()) {
+        fail("encoding failed");
+      } else if (!pushOutput(force)) {
+        return false;
+      } else if (encoder.hasMoreOutput()) {
+        buffer = encoder.pull();
+      } else if (encoder.hasRemainingInput()) {
+        encoder.push(op, 0);
+      } else if (hasInput) {
+        encoder.push(op, inputBuffer.limit());
+        hasInput = false;
+      } else {
+        inputBuffer.clear();
+        return true;
+      }
+    }
+  }
+
+  void flush() throws IOException {
+    encode(EncoderJNI.Operation.FLUSH);
+  }
+
+  void close() throws IOException {
+    if (closed) {
+      return;
+    }
+    closed = true;
+    try {
+      encode(EncoderJNI.Operation.FINISH);
+    } finally {
+      encoder.destroy();
+      destination.close();
+    }
+  }
+
+  /**
+   * Encodes the given data buffer.
+   */
+  public static byte[] compress(byte[] data, Parameters params) throws IOException {
+    EncoderJNI.Wrapper encoder = new EncoderJNI.Wrapper(
+        data.length, params.quality, params.lgwin, null);
+    ArrayList<byte[]> output = new ArrayList<byte[]>();
+    int totalOutputSize = 0;
+    try {
+      encoder.getInputBuffer().put(data);
+      encoder.push(EncoderJNI.Operation.FINISH, data.length);
+      while (true) {
+        if (!encoder.isSuccess()) {
+          throw new IOException("encoding failed");
+        } else if (encoder.hasMoreOutput()) {
+          ByteBuffer buffer = encoder.pull();
+          byte[] chunk = new byte[buffer.remaining()];
+          buffer.get(chunk);
+          output.add(chunk);
+          totalOutputSize += chunk.length;
+        } else if (encoder.hasRemainingInput()) {
+          encoder.push(EncoderJNI.Operation.FINISH, 0);
+        } else {
+          break;
+        }
+      }
+    } finally {
+      encoder.destroy();
+    }
+    if (output.size() == 1) {
+      return output.get(0);
+    }
+    byte[] result = new byte[totalOutputSize];
+    int offset = 0;
+    for (byte[] chunk : output) {
+      System.arraycopy(chunk, 0, result, offset, chunk.length);
+      offset += chunk.length;
+    }
+    return result;
+  }
+
+  public static byte[] compress(byte[] data) throws IOException {
+    return compress(data, new Parameters());
+  }
+}
diff --git a/java/org/brotli/wrapper/enc/EncoderJNI.java b/java/org/brotli/wrapper/enc/EncoderJNI.java
new file mode 100755
index 0000000..dd7cff3
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/EncoderJNI.java
@@ -0,0 +1,111 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.enc;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+/**
+ * JNI wrapper for brotli encoder.
+ */
+class EncoderJNI {
+  private static native ByteBuffer nativeCreate(long[] context, ByteBuffer customDictionary);
+  private static native void nativePush(long[] context, int length);
+  private static native ByteBuffer nativePull(long[] context);
+  private static native void nativeDestroy(long[] context);
+
+  enum Operation {
+    PROCESS,
+    FLUSH,
+    FINISH
+  }
+
+  static class Wrapper {
+    protected final long[] context = new long[4];
+    private final ByteBuffer inputBuffer;
+
+    Wrapper(int inputBufferSize, int quality, int lgwin, ByteBuffer customDictionary)
+        throws IOException {
+      if (customDictionary != null && !customDictionary.isDirect()) {
+        throw new IllegalArgumentException("LZ77 dictionary must be direct ByteBuffer");
+      }
+      this.context[1] = inputBufferSize;
+      this.context[2] = quality;
+      this.context[3] = lgwin;
+      this.inputBuffer = nativeCreate(this.context, customDictionary);
+      if (this.context[0] == 0) {
+        throw new IOException("failed to initialize native brotli encoder");
+      }
+      this.context[1] = 1;
+      this.context[2] = 0;
+      this.context[3] = 0;
+    }
+
+    void push(Operation op, int length) {
+      if (length < 0) {
+        throw new IllegalArgumentException("negative block length");
+      }
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli encoder is already destroyed");
+      }
+      if (!isSuccess() || hasMoreOutput()) {
+        throw new IllegalStateException("pushing input to encoder in unexpected state");
+      }
+      if (hasRemainingInput() && length != 0) {
+        throw new IllegalStateException("pushing input to encoder over previous input");
+      }
+      context[1] = op.ordinal();
+      nativePush(context, length);
+    }
+
+    boolean isSuccess() {
+      return context[1] != 0;
+    }
+
+    boolean hasMoreOutput() {
+      return context[2] != 0;
+    }
+
+    boolean hasRemainingInput() {
+      return context[3] != 0;
+    }
+
+    ByteBuffer getInputBuffer() {
+      return inputBuffer;
+    }
+
+    ByteBuffer pull() {
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli encoder is already destroyed");
+      }
+      if (!isSuccess() || !hasMoreOutput()) {
+        throw new IllegalStateException("pulling while data is not ready");
+      }
+      return nativePull(context);
+    }
+
+    /**
+     * Releases native resources.
+     */
+    void destroy() {
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli encoder is already destroyed");
+      }
+      nativeDestroy(context);
+      context[0] = 0;
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+      if (context[0] != 0) {
+        /* TODO: log resource leak? */
+        destroy();
+      }
+      super.finalize();
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/enc/EncoderTest.java b/java/org/brotli/wrapper/enc/EncoderTest.java
new file mode 100755
index 0000000..8328d45
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/EncoderTest.java
@@ -0,0 +1,83 @@
+package org.brotli.wrapper.enc;
+
+import static org.junit.Assert.assertEquals;
+
+import org.brotli.integration.BundleHelper;
+import org.brotli.wrapper.dec.BrotliInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+import org.junit.runner.RunWith;
+import org.junit.runners.AllTests;
+
+/** Tests for {@link org.brotli.wrapper.enc.Encoder}. */
+@RunWith(AllTests.class)
+public class EncoderTest {
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni.so").getAbsolutePath());
+  }
+
+  static InputStream getBundle() throws IOException {
+    return new FileInputStream(System.getProperty("TEST_BUNDLE"));
+  }
+
+  /** Creates a test suite. */
+  public static TestSuite suite() throws IOException {
+    TestSuite suite = new TestSuite();
+    InputStream bundle = getBundle();
+    try {
+      List<String> entries = BundleHelper.listEntries(bundle);
+      for (String entry : entries) {
+        suite.addTest(new EncoderTestCase(entry));
+      }
+    } finally {
+      bundle.close();
+    }
+    return suite;
+  }
+
+  /** Test case with a unique name. */
+  static class EncoderTestCase extends TestCase {
+    final String entryName;
+    EncoderTestCase(String entryName) {
+      super("EncoderTest." + entryName);
+      this.entryName = entryName;
+    }
+
+    @Override
+    protected void runTest() throws Throwable {
+      EncoderTest.run(entryName);
+    }
+  }
+
+  private static void run(String entryName) throws Throwable {
+    InputStream bundle = getBundle();
+    byte[] original;
+    try {
+      original = BundleHelper.readEntry(bundle, entryName);
+    } finally {
+      bundle.close();
+    }
+    if (original == null) {
+      throw new RuntimeException("Can't read bundle entry: " + entryName);
+    }
+
+    byte[] compressed = Encoder.compress(original, new Encoder.Parameters().setQuality(6));
+
+    InputStream decoder = new BrotliInputStream(new ByteArrayInputStream(compressed));
+    try {
+      long originalCrc = BundleHelper.fingerprintStream(new ByteArrayInputStream(original));
+      long crc = BundleHelper.fingerprintStream(decoder);
+      assertEquals(originalCrc, crc);
+    } finally {
+      decoder.close();
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/enc/UseCustomDictionaryTest.java b/java/org/brotli/wrapper/enc/UseCustomDictionaryTest.java
new file mode 100755
index 0000000..d46f997
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/UseCustomDictionaryTest.java
@@ -0,0 +1,104 @@
+package org.brotli.wrapper.enc;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import org.brotli.integration.BundleHelper;
+import org.brotli.wrapper.common.BrotliCommon;
+import org.brotli.wrapper.dec.BrotliInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+import java.util.List;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+import org.junit.runner.RunWith;
+import org.junit.runners.AllTests;
+
+/** Tests for compression / decompression aided with LZ77 dictionary. */
+@RunWith(AllTests.class)
+public class UseCustomDictionaryTest {
+
+  // TODO: remove when Bazel get JNI support.
+  static {
+    System.load(new java.io.File(new java.io.File(System.getProperty("java.library.path")),
+        "liblibjni.so").getAbsolutePath());
+  }
+
+  static InputStream getBundle() throws IOException {
+    return new FileInputStream(System.getProperty("TEST_BUNDLE"));
+  }
+
+  /** Creates a test suite. */
+  public static TestSuite suite() throws IOException {
+    TestSuite suite = new TestSuite();
+    InputStream bundle = getBundle();
+    try {
+      List<String> entries = BundleHelper.listEntries(bundle);
+      for (String entry : entries) {
+        suite.addTest(new UseCustomDictionaryTestCase(entry));
+      }
+    } finally {
+      bundle.close();
+    }
+    return suite;
+  }
+
+  /** Test case with a unique name. */
+  static class UseCustomDictionaryTestCase extends TestCase {
+    final String entryName;
+    UseCustomDictionaryTestCase(String entryName) {
+      super("UseCustomDictionaryTest." + entryName);
+      this.entryName = entryName;
+    }
+
+    @Override
+    protected void runTest() throws Throwable {
+      UseCustomDictionaryTest.run(entryName);
+    }
+  }
+
+  private static void run(String entryName) throws Throwable {
+    InputStream bundle = getBundle();
+    byte[] original;
+    try {
+      original = BundleHelper.readEntry(bundle, entryName);
+    } finally {
+      bundle.close();
+    }
+
+    if (original == null) {
+      throw new RuntimeException("Can't read bundle entry: " + entryName);
+    }
+
+    ByteBuffer dictionary = BrotliCommon.makeNative(original);
+
+    ByteArrayOutputStream dst = new ByteArrayOutputStream();
+    OutputStream encoder = new BrotliOutputStream(dst,
+        new Encoder.Parameters().setQuality(11).setWindow(23), 1 << 23, dictionary);
+    try {
+      encoder.write(original);
+    } finally {
+      encoder.close();
+    }
+
+    byte[] compressed = dst.toByteArray();
+
+    // Just copy self from LZ77 dictionary -> ultimate compression ratio.
+    assertTrue(compressed.length < 80 + original.length / 65536);
+
+    InputStream decoder = new BrotliInputStream(new ByteArrayInputStream(compressed),
+        1 << 23, dictionary);
+    try {
+      long originalCrc = BundleHelper.fingerprintStream(new ByteArrayInputStream(original));
+      long crc = BundleHelper.fingerprintStream(decoder);
+      assertEquals(originalCrc, crc);
+    } finally {
+      decoder.close();
+    }
+  }
+}
diff --git a/java/org/brotli/wrapper/enc/encoder_jni.cc b/java/org/brotli/wrapper/enc/encoder_jni.cc
new file mode 100755
index 0000000..adc7c12
--- /dev/null
+++ b/java/org/brotli/wrapper/enc/encoder_jni.cc
@@ -0,0 +1,224 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+#include <jni.h>
+
+#include <new>
+
+#include <brotli/encode.h>
+
+namespace {
+/* A structure used to persist the encoder's state in between calls. */
+typedef struct EncoderHandle {
+  BrotliEncoderState* state;
+
+  jobject custom_dictionary_ref;
+
+  uint8_t* input_start;
+  size_t input_offset;
+  size_t input_last;
+} EncoderHandle;
+
+/* Obtain handle from opaque pointer. */
+EncoderHandle* getHandle(void* opaque) {
+  return static_cast<EncoderHandle*>(opaque);
+}
+
+}  /* namespace */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Creates a new Encoder.
+ *
+ * Cookie to address created encoder is stored in out_cookie. In case of failure
+ * cookie is 0.
+ *
+ * @param ctx {out_cookie, in_directBufferSize, in_quality, in_lgwin} tuple
+ * @returns direct ByteBuffer if directBufferSize is not 0; otherwise null
+ */
+JNIEXPORT jobject JNICALL
+Java_org_brotli_wrapper_enc_EncoderJNI_nativeCreate(
+    JNIEnv* env, jobject /*jobj*/, jlongArray ctx, jobject custom_dictionary) {
+  bool ok = true;
+  EncoderHandle* handle = nullptr;
+  jlong context[4];
+  env->GetLongArrayRegion(ctx, 0, 4, context);
+  size_t input_size = context[1];
+  context[0] = 0;
+  handle = new (std::nothrow) EncoderHandle();
+  ok = !!handle;
+
+  if (ok) {
+    handle->custom_dictionary_ref = nullptr;
+    handle->input_offset = 0;
+    handle->input_last = 0;
+    handle->input_start = nullptr;
+
+    if (input_size == 0) {
+      ok = false;
+    } else {
+      handle->input_start = new (std::nothrow) uint8_t[input_size];
+      ok = !!handle->input_start;
+    }
+  }
+
+  if (ok) {
+    handle->state = BrotliEncoderCreateInstance(nullptr, nullptr, nullptr);
+    ok = !!handle->state;
+  }
+
+  if (ok) {
+    int quality = context[2];
+    if (quality >= 0) {
+      BrotliEncoderSetParameter(handle->state, BROTLI_PARAM_QUALITY, quality);
+    }
+    int lgwin = context[3];
+    if (lgwin >= 0) {
+      BrotliEncoderSetParameter(handle->state, BROTLI_PARAM_LGWIN, lgwin);
+    }
+  }
+
+  if (ok && !!custom_dictionary) {
+    handle->custom_dictionary_ref = env->NewGlobalRef(custom_dictionary);
+    if (!!handle->custom_dictionary_ref) {
+      uint8_t* custom_dictionary_address = static_cast<uint8_t*>(
+          env->GetDirectBufferAddress(handle->custom_dictionary_ref));
+      if (!!custom_dictionary_address) {
+        jlong capacity =
+            env->GetDirectBufferCapacity(handle->custom_dictionary_ref);
+        ok = (capacity > 0) && (capacity < (1 << 24));
+        if (ok) {
+          size_t custom_dictionary_size = static_cast<size_t>(capacity);
+          BrotliEncoderSetCustomDictionary(
+              handle->state, custom_dictionary_size, custom_dictionary_address);
+        }
+      } else {
+        ok = false;
+      }
+    } else {
+      ok = false;
+    }
+  }
+
+  if (ok) {
+    /* TODO: future versions (e.g. when 128-bit architecture comes)
+                     might require thread-safe cookie<->handle mapping. */
+    context[0] = reinterpret_cast<jlong>(handle);
+  } else if (!!handle) {
+    if (!!handle->custom_dictionary_ref) {
+      env->DeleteGlobalRef(handle->custom_dictionary_ref);
+    }
+    if (!!handle->input_start) delete[] handle->input_start;
+    delete handle;
+  }
+
+  env->SetLongArrayRegion(ctx, 0, 1, context);
+
+  if (!ok) {
+    return nullptr;
+  }
+
+  return env->NewDirectByteBuffer(handle->input_start, input_size);
+}
+
+/**
+ * Push data to encoder.
+ *
+ * @param ctx {in_cookie, in_operation_out_success, out_has_more_output,
+ *             out_has_remaining_input} tuple
+ * @param input_length number of bytes provided in input or direct input;
+ *                     0 to process further previous input
+ */
+JNIEXPORT void JNICALL
+Java_org_brotli_wrapper_enc_EncoderJNI_nativePush(
+    JNIEnv* env, jobject /*jobj*/, jlongArray ctx, jint input_length) {
+  jlong context[4];
+  env->GetLongArrayRegion(ctx, 0, 4, context);
+  EncoderHandle* handle = getHandle(reinterpret_cast<void*>(context[0]));
+  int operation = context[1];
+  context[1] = 0;  /* ERROR */
+  env->SetLongArrayRegion(ctx, 0, 4, context);
+
+  BrotliEncoderOperation op;
+  switch (operation) {
+    case 0: op = BROTLI_OPERATION_PROCESS; break;
+    case 1: op = BROTLI_OPERATION_FLUSH; break;
+    case 2: op = BROTLI_OPERATION_FINISH; break;
+    default: return;  /* ERROR */
+  }
+
+  if (input_length != 0) {
+    /* Still have unconsumed data. Workflow is broken. */
+    if (handle->input_offset < handle->input_last) {
+      return;
+    }
+    handle->input_offset = 0;
+    handle->input_last = input_length;
+  }
+
+  /* Actual compression. */
+  const uint8_t* in = handle->input_start + handle->input_offset;
+  size_t in_size = handle->input_last - handle->input_offset;
+  size_t out_size = 0;
+  BROTLI_BOOL status = BrotliEncoderCompressStream(
+      handle->state, op, &in_size, &in, &out_size, nullptr, nullptr);
+  handle->input_offset = handle->input_last - in_size;
+  if (!!status) {
+    context[1] = 1;
+    context[2] = BrotliEncoderHasMoreOutput(handle->state) ? 1 : 0;
+    context[3] = (handle->input_offset != handle->input_last) ? 1 : 0;
+  }
+  env->SetLongArrayRegion(ctx, 0, 4, context);
+}
+
+/**
+ * Pull decompressed data from encoder.
+ *
+ * @param ctx {in_cookie, out_success, out_has_more_output,
+ *             out_has_remaining_input} tuple
+ * @returns direct ByteBuffer; all the produced data MUST be consumed before
+ *          any further invocation; null in case of error
+ */
+JNIEXPORT jobject JNICALL
+Java_org_brotli_wrapper_enc_EncoderJNI_nativePull(
+    JNIEnv* env, jobject /*jobj*/, jlongArray ctx) {
+  jlong context[4];
+  env->GetLongArrayRegion(ctx, 0, 4, context);
+  EncoderHandle* handle = getHandle(reinterpret_cast<void*>(context[0]));
+  size_t data_length = 0;
+  const uint8_t* data = BrotliEncoderTakeOutput(handle->state, &data_length);
+  context[1] = 1;
+  context[2] = BrotliEncoderHasMoreOutput(handle->state) ? 1 : 0;
+  context[3] = (handle->input_offset != handle->input_last) ? 1 : 0;
+  env->SetLongArrayRegion(ctx, 0, 4, context);
+  return env->NewDirectByteBuffer(const_cast<uint8_t*>(data), data_length);
+}
+
+/**
+ * Releases all used resources.
+ *
+ * @param ctx {in_cookie} tuple
+ */
+JNIEXPORT void JNICALL
+Java_org_brotli_wrapper_enc_EncoderJNI_nativeDestroy(
+    JNIEnv* env, jobject /*jobj*/, jlongArray ctx) {
+  jlong context[2];
+  env->GetLongArrayRegion(ctx, 0, 2, context);
+  EncoderHandle* handle = getHandle(reinterpret_cast<void*>(context[0]));
+  BrotliEncoderDestroyInstance(handle->state);
+  if (!!handle->custom_dictionary_ref) {
+    env->DeleteGlobalRef(handle->custom_dictionary_ref);
+  }
+  delete[] handle->input_start;
+  delete handle;
+}
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/scripts/appveyor.yml b/scripts/appveyor.yml
index 617f324..b5b1294 100644
--- a/scripts/appveyor.yml
+++ b/scripts/appveyor.yml
@@ -62,7 +62,7 @@
         pip install --disable-pip-version-check --user --upgrade pip
 
         # install/upgrade setuptools and wheel to build packages
-        pip install --upgrade setuptools wheel
+        pip install --upgrade setuptools six wheel
       }
 
 before_build: