| /** |
| ******************************************************************************* |
| * Copyright (C) 2006, International Business Machines Corporation and * |
| * others. All Rights Reserved. * |
| ******************************************************************************* |
| * |
| ******************************************************************************* |
| */ |
| |
| package com.ibm.icu.charset; |
| |
| import java.io.ByteArrayInputStream; |
| import java.io.InputStreamReader; |
| import java.lang.reflect.Constructor; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.nio.ByteBuffer; |
| import java.nio.charset.Charset; |
| import java.nio.charset.IllegalCharsetNameException; |
| import java.nio.charset.UnsupportedCharsetException; |
| import java.util.HashMap; |
| |
| import com.ibm.icu.lang.UCharacter; |
| /** |
| * <p>A subclass of java.nio.Charset for providing implementation of ICU's charset converters. |
| * This API is used to convert codepage or character encoded data to and |
| * from UTF-16. You can open a converter with {@link Charset#forName } and {@link #forNameICU }. With that |
| * converter, you can get its properties, set options, convert your data.</p> |
| * |
| * <p>Since many software programs recogize different converter names for |
| * different types of converters, there are other functions in this API to |
| * iterate over the converter aliases. |
| * |
| * @draft ICU 3.6 |
| * @provisional This API might change or be removed in a future release. |
| */ |
| public abstract class CharsetICU extends Charset{ |
| |
| String icuCanonicalName; |
| String javaCanonicalName; |
| int options; |
| |
| float maxCharsPerByte; |
| |
| boolean useFallback; |
| |
| String name; /* +4: 60 internal name of the converter- invariant chars */ |
| |
| int codepage; /* +64: 4 codepage # (now IBM-$codepage) */ |
| |
| byte platform; /* +68: 1 platform of the converter (only IBM now) */ |
| byte conversionType; /* +69: 1 conversion type */ |
| |
| int minBytesPerChar; /* +70: 1 Minimum # bytes per char in this codepage */ |
| int maxBytesPerChar; /* +71: 1 Maximum # bytes output per UChar in this codepage */ |
| |
| byte subChar[/*UCNV_MAX_SUBCHAR_LEN*/]; /* +72: 4 [note: 4 and 8 byte boundary] */ |
| byte subCharLen; /* +76: 1 */ |
| |
| byte hasToUnicodeFallback; /* +77: 1 UBool needs to be changed to UBool to be consistent across platform */ |
| byte hasFromUnicodeFallback; /* +78: 1 */ |
| short unicodeMask; /* +79: 1 bit 0: has supplementary bit 1: has single surrogates */ |
| byte subChar1; /* +80: 1 single-byte substitution character for IBM MBCS (0 if none) */ |
| byte reserved[/*19*/]; /* +81: 19 to round out the structure */ |
| |
| |
| /** |
| * |
| * @param icuCanonicalName |
| * @param canonicalName |
| * @param aliases |
| * @draft ICU 3.6 |
| * @provisional This API might change or be removed in a future release. |
| */ |
| protected CharsetICU(String icuCanonicalName, String canonicalName, String[] aliases) { |
| super(canonicalName,aliases); |
| if(canonicalName.length() == 0){ |
| throw new IllegalCharsetNameException(canonicalName); |
| } |
| this.javaCanonicalName = canonicalName; |
| this.icuCanonicalName = icuCanonicalName; |
| } |
| |
| /** |
| * Ascertains if a charset is a sub set of this charset |
| * Implements the abstract method of super class. |
| * @param cs charset to test |
| * @return true if the given charset is a subset of this charset |
| * @stable ICU 3.6 |
| */ |
| public boolean contains(Charset cs){ |
| if (null == cs) { |
| return false; |
| } else if (this.equals(cs)) { |
| return true; |
| } |
| return false; |
| } |
| private static final HashMap algorithmicCharsets = new HashMap(); |
| static{ |
| /*algorithmicCharsets.put("BOCU-1", "com.ibm.icu.charset.CharsetBOCU1" ); |
| algorithmicCharsets.put("CESU-8", "com.ibm.icu.charset.CharsetCESU8" ); |
| algorithmicCharsets.put("HZ", "com.ibm.icu.charset.CharsetHZ" ); |
| algorithmicCharsets.put("imapmailboxname", "com.ibm.icu.charset.CharsetIMAP" ); |
| algorithmicCharsets.put("ISCII", "com.ibm.icu.charset.CharsetISCII" ); |
| algorithmicCharsets.put("iso2022", "com.ibm.icu.charset.CharsetISO2022" ); |
| algorithmicCharsets.put("lmbcs1", "com.ibm.icu.charset.CharsetLMBCS1" ); |
| algorithmicCharsets.put("lmbcs11", "com.ibm.icu.charset.CharsetLMBCS11" ); |
| algorithmicCharsets.put("lmbcs16", "com.ibm.icu.charset.CharsetLMBCS16" ); |
| algorithmicCharsets.put("lmbcs17", "com.ibm.icu.charset.CharsetLMBCS17" ); |
| algorithmicCharsets.put("lmbcs18", "com.ibm.icu.charset.CharsetLMBCS18" ); |
| algorithmicCharsets.put("lmbcs19", "com.ibm.icu.charset.CharsetLMBCS19" ); |
| algorithmicCharsets.put("lmbcs2", "com.ibm.icu.charset.CharsetLMBCS2" ); |
| algorithmicCharsets.put("lmbcs3", "com.ibm.icu.charset.CharsetLMBCS3" ); |
| algorithmicCharsets.put("lmbcs4", "com.ibm.icu.charset.CharsetLMBCS4" ); |
| algorithmicCharsets.put("lmbcs5", "com.ibm.icu.charset.CharsetLMBCS5" ); |
| algorithmicCharsets.put("lmbcs6", "com.ibm.icu.charset.CharsetLMBCS6" ); |
| algorithmicCharsets.put("lmbcs8", "com.ibm.icu.charset.CharsetLMBCS8" ) |
| algorithmicCharsets.put("scsu", "com.ibm.icu.charset.CharsetSCSU" ); |
| algorithmicCharsets.put("UTF-7", "com.ibm.icu.charset.CharsetUTF7" ); |
| */ |
| algorithmicCharsets.put("US-ASCII", "com.ibm.icu.charset.CharsetASCII" ); |
| algorithmicCharsets.put("ISO-8859-1", "com.ibm.icu.charset.Charset88591" ); |
| algorithmicCharsets.put("UTF-16", "com.ibm.icu.charset.CharsetUTF16" ); |
| algorithmicCharsets.put("UTF-16BE", "com.ibm.icu.charset.CharsetUTF16BE" ); |
| algorithmicCharsets.put("UTF-16LE", "com.ibm.icu.charset.CharsetUTF16LE" ); |
| algorithmicCharsets.put("UTF16_OppositeEndian", "com.ibm.icu.charset.CharsetUTF16LE" ); |
| algorithmicCharsets.put("UTF16_PlatformEndian", "com.ibm.icu.charset.CharsetUTF16" ); |
| algorithmicCharsets.put("UTF-32", "com.ibm.icu.charset.CharsetUTF32" ); |
| algorithmicCharsets.put("UTF-32BE", "com.ibm.icu.charset.CharsetUTF32BE" ); |
| algorithmicCharsets.put("UTF-32LE", "com.ibm.icu.charset.CharsetUTF32LE" ); |
| algorithmicCharsets.put("UTF32_OppositeEndian", "com.ibm.icu.charset.CharsetUTF32LE" ); |
| algorithmicCharsets.put("UTF32_PlatformEndian", "com.ibm.icu.charset.CharsetUTF32" ); |
| algorithmicCharsets.put("UTF-8", "com.ibm.icu.charset.CharsetUTF8" ); |
| } |
| |
| /*public*/ static final Charset getCharset(String icuCanonicalName, String javaCanonicalName, String[] aliases){ |
| String className = (String) algorithmicCharsets.get(icuCanonicalName); |
| if(className==null){ |
| //all the cnv files are loaded as MBCS |
| className = "com.ibm.icu.charset.CharsetMBCS"; |
| } |
| try{ |
| CharsetICU conv = null; |
| Class cs = Class.forName(className); |
| Class[] paramTypes = new Class[]{ String.class, String.class, String[].class}; |
| final Constructor c = cs.getConstructor(paramTypes); |
| Object[] params = new Object[]{ icuCanonicalName, javaCanonicalName, aliases}; |
| |
| // Run constructor |
| try { |
| Object obj = c.newInstance(params); |
| if(obj!=null && obj instanceof CharsetICU){ |
| conv = (CharsetICU)obj; |
| return conv; |
| } |
| }catch (InvocationTargetException e) { |
| throw new UnsupportedCharsetException( icuCanonicalName+": "+"Could not load " + className+ ". Exception:" + e.getTargetException()); |
| } |
| }catch(ClassNotFoundException ex){ |
| }catch(NoSuchMethodException ex){ |
| }catch (IllegalAccessException ex){ |
| }catch (InstantiationException ex){ |
| } |
| throw new UnsupportedCharsetException( icuCanonicalName+": "+"Could not load " + className); |
| } |
| |
| static final boolean isSurrogate(int c){ |
| return (((c)&0xfffff800)==0xd800); |
| } |
| |
| /** |
| * Always use fallbacks from codepage to Unicode? |
| * @draft ICU 3.6 |
| * @provisional This API might change or be removed in a future release. |
| */ |
| final boolean isToUUseFallback() { |
| return true; |
| } |
| |
| /** |
| * Use fallbacks from Unicode to codepage when useFallback or for private-use code points |
| * @param c A codepoint |
| * @draft ICU 3.6 |
| * @provisional This API might change or be removed in a future release. |
| */ |
| final boolean isFromUUseFallback(int c) { |
| return (useFallback) || isPrivateUse(c); |
| } |
| |
| /** |
| * Returns the default charset name |
| * @draft ICU 3.6 |
| * @provisional This API might change or be removed in a future release. |
| */ |
| static final String getDefaultCharsetName(){ |
| String defaultEncoding = new InputStreamReader(new ByteArrayInputStream(new byte[0])).getEncoding(); |
| return defaultEncoding; |
| } |
| |
| static final boolean isPrivateUse(int c) { |
| return (UCharacter.getType(c) == UCharacter.PRIVATE_USE); |
| } |
| |
| /** |
| * Returns a charset object for the named charset. |
| * This method gurantee that ICU charset is returned when |
| * available. If the ICU charset provider does not support |
| * the specified charset, then try other charset providers |
| * including the standard Java charset provider. |
| * |
| * @param charsetName The name of the requested charset, |
| * may be either a canonical name or an alias |
| * @return A charset object for the named charset |
| * @throws IllegalCharsetNameException If the given charset name |
| * is illegal |
| * @throws UnsupportedCharsetException If no support for the |
| * named charset is available in this instance of th Java |
| * virtual machine |
| * @draft ICU 3.6 |
| * @provisional This API might change or be removed in a future release. |
| */ |
| public static Charset forNameICU(String charsetName) throws IllegalCharsetNameException, UnsupportedCharsetException { |
| CharsetProviderICU icuProvider = new CharsetProviderICU(); |
| CharsetICU cs = (CharsetICU) icuProvider.charsetForName(charsetName); |
| if (cs != null) { |
| return cs; |
| } |
| return Charset.forName(charsetName); |
| } |
| |
| /** |
| * This follows ucnv.c method ucnv_detectUnicodeSignature() to detect the |
| * start of the stream for example U+FEFF (the Unicode BOM/signature |
| * character) that can be ignored. |
| * |
| * Detects Unicode signature byte sequences at the start of the byte stream |
| * and returns number of bytes of the BOM of the indicated Unicode charset. |
| * 0 is returned when no Unicode signature is recognized. |
| * |
| */ |
| static String detectUnicodeSignature(ByteBuffer source) { |
| int signatureLength = 0; // number of bytes of the signature |
| final int SIG_MAX_LEN = 5; |
| String sigUniCharset = null; // states what unicode charset is the BOM |
| int i = 0; |
| |
| /* |
| * initial 0xa5 bytes: make sure that if we read <SIG_MAX_LEN bytes we |
| * don't misdetect something |
| */ |
| byte start[] = { (byte) 0xa5, (byte) 0xa5, (byte) 0xa5, (byte) 0xa5, |
| (byte) 0xa5 }; |
| |
| while (i < source.remaining() && i < SIG_MAX_LEN) { |
| start[i] = source.get(i); |
| i++; |
| } |
| |
| if (start[0] == (byte) 0xFE && start[1] == (byte) 0xFF) { |
| signatureLength = 2; |
| sigUniCharset = "UTF-16BE"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } else if (start[0] == (byte) 0xFF && start[1] == (byte) 0xFE) { |
| if (start[2] == (byte) 0x00 && start[3] == (byte) 0x00) { |
| signatureLength = 4; |
| sigUniCharset = "UTF-32LE"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } else { |
| signatureLength = 2; |
| sigUniCharset = "UTF-16LE"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } |
| } else if (start[0] == (byte) 0xEF && start[1] == (byte) 0xBB |
| && start[2] == (byte) 0xBF) { |
| signatureLength = 3; |
| sigUniCharset = "UTF-8"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } else if (start[0] == (byte) 0x00 && start[1] == (byte) 0x00 |
| && start[2] == (byte) 0xFE && start[3] == (byte) 0xFF) { |
| signatureLength = 4; |
| sigUniCharset = "UTF-32BE"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } else if (start[0] == (byte) 0x0E && start[1] == (byte) 0xFE |
| && start[2] == (byte) 0xFF) { |
| signatureLength = 3; |
| sigUniCharset = "SCSU"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } else if (start[0] == (byte) 0xFB && start[1] == (byte) 0xEE |
| && start[2] == (byte) 0x28) { |
| signatureLength = 3; |
| sigUniCharset = "BOCU-1"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } else if (start[0] == (byte) 0x2B && start[1] == (byte) 0x2F |
| && start[2] == (byte) 0x76) { |
| |
| if (start[3] == (byte) 0x38 && start[4] == (byte) 0x2D) { |
| signatureLength = 5; |
| sigUniCharset = "UTF-7"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } else if (start[3] == (byte) 0x38 || start[3] == (byte) 0x39 |
| || start[3] == (byte) 0x2B || start[3] == (byte) 0x2F) { |
| signatureLength = 4; |
| sigUniCharset = "UTF-7"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } |
| } else if (start[0] == (byte) 0xDD && start[2] == (byte) 0x73 |
| && start[2] == (byte) 0x66 && start[3] == (byte) 0x73) { |
| signatureLength = 4; |
| sigUniCharset = "UTF-EBCDIC"; |
| source.position(signatureLength); |
| return sigUniCharset; |
| } |
| |
| /* no known Unicode signature byte sequence recognized */ |
| return null; |
| } |
| |
| } |
| |