/*
 * *****************************************************************************
 * Copyright (C) 2005-2008, International Business Machines Corporation and    *
 * others. All Rights Reserved.                                                *
 * *****************************************************************************
 */

package com.ibm.icu.impl;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.lang.ref.SoftReference;
import java.net.URL;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Locale;
import java.util.Map;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
import java.util.Set;

import com.ibm.icu.impl.URLHandler.URLVisitor;
import com.ibm.icu.util.StringTokenizer;
import com.ibm.icu.util.ULocale;
import com.ibm.icu.util.UResourceBundle;
import com.ibm.icu.util.UResourceBundleIterator;
import com.ibm.icu.util.VersionInfo;

public  class ICUResourceBundle extends UResourceBundle {
    /**
     * The data path to be used with getBundleInstance API
     * @draft ICU 3.0
     */
    protected static final String ICU_DATA_PATH = "com/ibm/icu/impl/";
    /**
     * The data path to be used with getBundleInstance API
     * @draft ICU 3.0
     */
    public static final String ICU_BUNDLE = "data/icudt" + VersionInfo.ICU_DATA_VERSION;

    /**
     * The base name of ICU data to be used with getBundleInstance API
     * @draft ICU 3.0
     */
    public static final String ICU_BASE_NAME = ICU_DATA_PATH + ICU_BUNDLE;

    /**
     * The base name of collation data to be used with getBundleInstance API
     * @draft ICU 3.0
     */
    public static final String ICU_COLLATION_BASE_NAME = ICU_BASE_NAME + "/coll";

    /**
     * The base name of rbbi data to be used with getData API
     * @draft ICU 3.6
     */
    public static final String ICU_BRKITR_NAME = "/brkitr";

    /**
     * The base name of rbbi data to be used with getBundleInstance API
     * @draft ICU 3.6
     */
    public static final String ICU_BRKITR_BASE_NAME = ICU_BASE_NAME + ICU_BRKITR_NAME;

    /**
     * The base name of rbnf data to be used with getBundleInstance API
     * @draft ICU 3.0
     */
    public static final String ICU_RBNF_BASE_NAME = ICU_BASE_NAME + "/rbnf";

    /**
     * The base name of transliterator data to be used with getBundleInstance API
     * @draft ICU 3.0
     */
    public static final String ICU_TRANSLIT_BASE_NAME = ICU_BASE_NAME + "/translit";

    /**
     * The actual path of the resource
     */
    protected String resPath;

    protected static final long UNSIGNED_INT_MASK = 0xffffffffL;

    /**
     * The class loader constant to be used with getBundleInstance API
     * @draft ICU 3.0
     */
    public static final ClassLoader ICU_DATA_CLASS_LOADER;
    static {
        ClassLoader loader = ICUData.class.getClassLoader();
        if (loader == null) { // boot class loader
            loader = ClassLoader.getSystemClassLoader();
        }
        ICU_DATA_CLASS_LOADER = loader;
    }

    /**
     * The name of the resource containing the installed locales
     * @draft ICU 3.0
     */
    protected static final String INSTALLED_LOCALES = "InstalledLocales";

    public static final int FROM_FALLBACK = 1, FROM_ROOT = 2, FROM_DEFAULT = 3, FROM_LOCALE = 4;

    private int loadingStatus = -1;

    public void setLoadingStatus(int newStatus) {
        loadingStatus = newStatus;
    }
    /**
     * Returns the loading status of a particular resource.
     *
     * @return FROM_FALLBACK if the resource is fetched from fallback bundle
     *         FROM_ROOT if the resource is fetched from root bundle.
     *         FROM_DEFAULT if the resource is fetched from the default locale.
     */
    public int getLoadingStatus() {
        return loadingStatus;
    }

    public void setLoadingStatus(String requestedLocale){
        String locale = getLocaleID();
        if(locale.equals("root")) {
            setLoadingStatus(FROM_ROOT);
        } else if(locale.equals(requestedLocale)) {
            setLoadingStatus(FROM_LOCALE);
        } else {
            setLoadingStatus(FROM_FALLBACK);
        }
     }


    /**
     * Returns the respath of this bundle
     * @return
     */
    public String getResPath(){
        return resPath;
    }

    /**
     * Returns a functionally equivalent locale, considering keywords as well, for the specified keyword.
     * @param baseName resource specifier
     * @param resName top level resource to consider (such as "collations")
     * @param keyword a particular keyword to consider (such as "collation" )
     * @param locID The requested locale
     * @param isAvailable If non-null, 1-element array of fillin parameter that indicates whether the
     * requested locale was available. The locale is defined as 'available' if it physically
     * exists within the specified tree and included in 'InstalledLocales'.
     * @return the locale
     * @internal ICU 3.0
     */
    public static final ULocale getFunctionalEquivalent(String baseName,
            String resName, String keyword, ULocale locID,
            boolean isAvailable[]) {
        String kwVal = locID.getKeywordValue(keyword);
        String baseLoc = locID.getBaseName();
        String defStr = null;
        ULocale parent = new ULocale(baseLoc);
        ULocale defLoc = null; // locale where default (found) resource is
        boolean lookForDefault = false; // true if kwVal needs to be set
        ULocale fullBase = null; // base locale of found (target) resource
        int defDepth = 0; // depth of 'default' marker
        int resDepth = 0; // depth of found resource;

        if ((kwVal == null) || (kwVal.length() == 0)
                || kwVal.equals(DEFAULT_TAG)) {
            kwVal = ""; // default tag is treated as no keyword
            lookForDefault = true;
        }

        // Check top level locale first
        ICUResourceBundle r = null;

        r = (ICUResourceBundle) UResourceBundle.getBundleInstance(baseName, parent);
        if (isAvailable != null) {
            isAvailable[0] = false;
            ULocale[] availableULocales = getAvailEntry(baseName).getULocaleList();
            for (int i = 0; i < availableULocales.length; i++) {
                if (parent.equals(availableULocales[i])) {
                    isAvailable[0] = true;
                    break;
                }
            }
        }
        // determine in which locale (if any) the currently relevant 'default' is
        do {
            try {
                ICUResourceBundle irb = (ICUResourceBundle) r.get(resName);
                defStr = irb.getString(DEFAULT_TAG);
                if (lookForDefault == true) {
                    kwVal = defStr;
                    lookForDefault = false;
                }
                defLoc = r.getULocale();
            } catch (MissingResourceException t) {
                // Ignore error and continue search.
            }
            if (defLoc == null) {
                r = (ICUResourceBundle) r.getParent();
                defDepth++;
            }
        } while ((r != null) && (defLoc == null));

        // Now, search for the named resource
        parent = new ULocale(baseLoc);
        r = (ICUResourceBundle) UResourceBundle.getBundleInstance(baseName, parent);
        // determine in which locale (if any) the named resource is located
        do {
            try {
                ICUResourceBundle irb = (ICUResourceBundle)r.get(resName);
                /* UResourceBundle urb = */irb.get(kwVal);
                fullBase = irb.getULocale();
                // If the get() completed, we have the full base locale
                // If we fell back to an ancestor of the old 'default',
                // we need to re calculate the "default" keyword.
                if ((fullBase != null) && ((resDepth) > defDepth)) {
                    defStr = irb.getString(DEFAULT_TAG);
                    defLoc = r.getULocale();
                    defDepth = resDepth;
                }
            } catch (MissingResourceException t) {
                // Ignore error,
            }
            if (fullBase == null) {
                r = (ICUResourceBundle) r.getParent();
                resDepth++;
            }
        } while ((r != null) && (fullBase == null));

        if (fullBase == null && // Could not find resource 'kwVal'
                (defStr != null) && // default was defined
                !defStr.equals(kwVal)) { // kwVal is not default
            // couldn't find requested resource. Fall back to default.
            kwVal = defStr; // Fall back to default.
            parent = new ULocale(baseLoc);
            r = (ICUResourceBundle) UResourceBundle.getBundleInstance(baseName, parent);
            resDepth = 0;
            // determine in which locale (if any) the named resource is located
            do {
                try {
                    ICUResourceBundle irb = (ICUResourceBundle)r.get(resName);
                    UResourceBundle urb = irb.get(kwVal);

                    // if we didn't fail before this..
                    fullBase = r.getULocale();

                    // If the fetched item (urb) is in a different locale than our outer locale (r/fullBase)
                    // then we are in a 'fallback' situation. treat as a missing resource situation.
                    if(!fullBase.toString().equals(urb.getLocale().toString())) {
                        fullBase = null; // fallback condition. Loop and try again.
                    }

                    // If we fell back to an ancestor of the old 'default',
                    // we need to re calculate the "default" keyword.
                    if ((fullBase != null) && ((resDepth) > defDepth)) {
                        defStr = irb.getString(DEFAULT_TAG);
                        defLoc = r.getULocale();
                        defDepth = resDepth;
                    }
                } catch (MissingResourceException t) {
                    // Ignore error, continue search.
                }
                if (fullBase == null) {
                    r = (ICUResourceBundle) r.getParent();
                    resDepth++;
                }
            } while ((r != null) && (fullBase == null));
        }

        if (fullBase == null) {
            throw new MissingResourceException(
                "Could not find locale containing requested or default keyword.",
                baseName, keyword + "=" + kwVal);
        }

        if (defStr.equals(kwVal) // if default was requested and
            && resDepth <= defDepth) { // default was set in same locale or child
            return fullBase; // Keyword value is default - no keyword needed in locale
        } else {
            return new ULocale(fullBase.toString() + "@" + keyword + "=" + kwVal);
        }
    }

    /**
     * Given a tree path and keyword, return a string enumeration of all possible values for that keyword.
     * @param baseName resource specifier
     * @param keyword a particular keyword to consider, must match a top level resource name
     * within the tree. (i.e. "collations")
     * @internal ICU 3.0
     */
    public static final String[] getKeywordValues(String baseName, String keyword) {
        Set keywords = new HashSet();
        ULocale locales[] = createULocaleList(baseName, ICU_DATA_CLASS_LOADER);
        int i;

        for (i = 0; i < locales.length; i++) {
            try {
                UResourceBundle b = UResourceBundle.getBundleInstance(baseName, locales[i]);
                // downcast to ICUResourceBundle?
                ICUResourceBundle irb = (ICUResourceBundle) (b.getObject(keyword));
                Enumeration e = irb.getKeys();
                Object s;
                while (e.hasMoreElements()) {
                    s = e.nextElement();
                    if ((s instanceof String) && !DEFAULT_TAG.equals(s)) {
                        // don't add 'default' items
                        keywords.add(s);
                    }
                }
            } catch (Throwable t) {
                //System.err.println("Error in - " + new Integer(i).toString()
                // + " - " + t.toString());
                // ignore the err - just skip that resource
            }
        }
        return (String[])keywords.toArray(new String[0]);
    }

    /**
     * This method performs multilevel fallback for fetching items from the
     * bundle e.g: If resource is in the form de__PHONEBOOK{ collations{
     * default{ "phonebook"} } } If the value of "default" key needs to be
     * accessed, then do: <code>
     *  UResourceBundle bundle = UResourceBundle.getBundleInstance("de__PHONEBOOK");
     *  ICUResourceBundle result = null;
     *  if(bundle instanceof ICUResourceBundle){
     *      result = ((ICUResourceBundle) bundle).getWithFallback("collations/default");
     *  }
     * </code>
     *
     * @param path
     *            The path to the required resource key
     * @return resource represented by the key
     * @exception MissingResourceException
     */
    public ICUResourceBundle getWithFallback(String path)
            throws MissingResourceException {
        ICUResourceBundle result = null;
        ICUResourceBundle actualBundle = this;

        // now recuse to pick up sub levels of the items
        result = findResourceWithFallback(path, actualBundle, null);

        if (result == null) {
            throw new MissingResourceException(
                "Can't find resource for bundle "
                + this.getClass().getName() + ", key " + getType(),
                path, getKey());
        }
        return result;
    }

    // will throw type mismatch exception if the resource is not a string
    public String getStringWithFallback(String path) throws MissingResourceException {
        return getWithFallback(path).getString();
    }

    /**
     * Return a set of the locale names supported by a collection of resource
     * bundles.
     *
     * @param bundlePrefix the prefix of the resource bundles to use.
     */
    public static Set getAvailableLocaleNameSet(String bundlePrefix) {
        return getAvailEntry(bundlePrefix).getLocaleNameSet();
    }

    /**
     * Return a set of all the locale names supported by a collection of
     * resource bundles.
     */
    public static Set getFullLocaleNameSet() {
        return getFullLocaleNameSet(ICU_BASE_NAME);
    }

    /**
     * Return a set of all the locale names supported by a collection of
     * resource bundles.
     *
     * @param bundlePrefix the prefix of the resource bundles to use.
     */
    public static Set getFullLocaleNameSet(String bundlePrefix) {
        return getAvailEntry(bundlePrefix).getFullLocaleNameSet();
    }

    /**
     * Return a set of the locale names supported by a collection of resource
     * bundles.
     */
    public static Set getAvailableLocaleNameSet() {
        return getAvailableLocaleNameSet(ICU_BASE_NAME);
    }

    /**
     * Get the set of Locales installed in the specified bundles.
     * @return the list of available locales
     * @draft ICU 3.0
     */
    public static final ULocale[] getAvailableULocales(String baseName) {
        return getAvailEntry(baseName).getULocaleList();
    }

    /**
     * Get the set of ULocales installed the base bundle.
     * @return the list of available locales
     * @draft ICU 3.0
     */
    public static final ULocale[] getAvailableULocales() {
        return getAvailableULocales(ICU_BASE_NAME);
    }

    /**
     * Get the set of Locales installed in the specified bundles.
     * @return the list of available locales
     * @draft ICU 3.0
     */
    public static final Locale[] getAvailableLocales(String baseName) {
        return getAvailEntry(baseName).getLocaleList();
    }

   /**
     * Get the set of Locales installed the base bundle.
     * @return the list of available locales
     * @draft ICU 3.0
     */
    public static final Locale[] getAvailableLocales() {
        return getAvailEntry(ICU_BASE_NAME).getLocaleList();
    }

    /**
     * Convert a list of ULocales to a list of Locales.  ULocales with a script code will not be converted
     * since they cannot be represented as a Locale.  This means that the two lists will <b>not</b> match
     * one-to-one, and that the returned list might be shorter than the input list.
     * @param ulocales a list of ULocales to convert to a list of Locales.
     * @return the list of converted ULocales
     * @draft ICU 3.0
     */
    public static final Locale[] getLocaleList(ULocale[] ulocales) {
        ArrayList list = new ArrayList();
        for (int i = 0; i < ulocales.length; i++) {
            // if the ULocale does not contain a script code
            // only then convert it to a Locale object
            if (ulocales[i].getScript().length() == 0) {
                list.add(ulocales[i].toLocale());
            }
        }
        return (Locale[]) list.toArray(new Locale[list.size()]);
    }

    /**
     * Returns the locale of this resource bundle. This method can be used after
     * a call to getBundle() to determine whether the resource bundle returned
     * really corresponds to the requested locale or is a fallback.
     *
     * @return the locale of this resource bundle
     */
    public Locale getLocale() {
        return getULocale().toLocale();
    }


    // ========== privates ==========
    private static final String ICU_RESOURCE_INDEX = "res_index";

    private static final String DEFAULT_TAG = "default";

    // Flag for enabling/disabling debugging code
    private static final boolean DEBUG = ICUDebug.enabled("localedata");

    // Cache for getAvailableLocales
    private static SoftReference GET_AVAILABLE_CACHE;
    private static final ULocale[] createULocaleList(String baseName,
            ClassLoader root) {
        // the canned list is a subset of all the available .res files, the idea
        // is we don't export them
        // all. gotta be a better way to do this, since to add a locale you have
        // to update this list,
        // and it's embedded in our binary resources.
        ICUResourceBundle bundle = (ICUResourceBundle) UResourceBundle.instantiateBundle(baseName, ICU_RESOURCE_INDEX, root, true);

        bundle = (ICUResourceBundle)bundle.get(INSTALLED_LOCALES);
        int length = bundle.getSize();
        int i = 0;
        ULocale[] locales = new ULocale[length];
        UResourceBundleIterator iter = bundle.getIterator();
        iter.reset();
        while (iter.hasNext()) {
            locales[i++] = new ULocale(iter.next().getKey());
        }
        bundle = null;
        return locales;
    }

    private static final Locale[] createLocaleList(String baseName) {
        ULocale[] ulocales = getAvailEntry(baseName).getULocaleList();
        return getLocaleList(ulocales);
    }

    private static final String[] createLocaleNameArray(String baseName,
            ClassLoader root) {
        ICUResourceBundle bundle = (ICUResourceBundle) UResourceBundle.instantiateBundle( baseName, ICU_RESOURCE_INDEX, root, true);
        bundle = (ICUResourceBundle)bundle.get(INSTALLED_LOCALES);
        int length = bundle.getSize();
        int i = 0;
        String[] locales = new String[length];
        UResourceBundleIterator iter = bundle.getIterator();
        iter.reset();
        while (iter.hasNext()) {
            locales[i++] = iter.next().getKey();
        }
        bundle = null;
        return locales;
    }

    private static final ArrayList createFullLocaleNameArray(
            final String baseName, final ClassLoader root) {

        ArrayList list = (ArrayList) java.security.AccessController
            .doPrivileged(new java.security.PrivilegedAction() {
                public Object run() {
                    // WebSphere class loader will return null for a raw
                    // directory name without trailing slash
                    String bn = baseName.endsWith("/")
                        ? baseName
                        : baseName + "/";

                    // look for prebuilt indices first
                    try {
                        InputStream s = root.getResourceAsStream(bn + ICU_RESOURCE_INDEX + ".txt");
                        if (s != null) {
                            ArrayList lst = new ArrayList();
                            BufferedReader br = new BufferedReader(new InputStreamReader(s, "ASCII"));
                            String line;
                            while ((line = br.readLine()) != null) {
                                if (line.length() != 0 && !line.startsWith("#")) {
                                    lst.add(line);
                                }
                            }
                            return lst;
                        }
                    } catch (IOException e) {
                        // swallow it
                    }

                    URL url = root.getResource(bn);
                    URLHandler handler = URLHandler.get(url);
                    if (handler != null) {
                        final ArrayList lst = new ArrayList();
                        URLVisitor v = new URLVisitor() {
                            public void visit(String s) {
                                if (s.endsWith(".res") && !"res_index.res".equals(s)) {
                                    lst.add(s.substring(0, s.length() - 4)); // strip '.res'
                                }
                            }
                        };
                        handler.guide(v, false);
                        return lst;
                    }

                    return null;
                }
            });

        return list;
    }

    private static Set createFullLocaleNameSet(String baseName) {
        ArrayList list = createFullLocaleNameArray(baseName,ICU_DATA_CLASS_LOADER);
        HashSet set = new HashSet();
        if(list==null){
            throw new MissingResourceException("Could not find "+  ICU_RESOURCE_INDEX, "", "");
        }
        set.addAll(list);
        return Collections.unmodifiableSet(set);
    }

    private static Set createLocaleNameSet(String baseName) {
        try {
            String[] locales = createLocaleNameArray(baseName, ICU_DATA_CLASS_LOADER);

            HashSet set = new HashSet();
            set.addAll(Arrays.asList(locales));
            return Collections.unmodifiableSet(set);
        } catch (MissingResourceException e) {
            if (DEBUG) {
                System.out.println("couldn't find index for bundleName: " + baseName);
                Thread.dumpStack();
            }
        }
        return Collections.EMPTY_SET;
    }

    /**
     * Holds the prefix, and lazily creates the Locale[] list or the locale name
     * Set as needed.
     */
    private static final class AvailEntry {
        private String prefix;
        private ULocale[] ulocales;
        private Locale[] locales;
        private Set nameSet;
        private Set fullNameSet;

        AvailEntry(String prefix) {
            this.prefix = prefix;
        }

        ULocale[] getULocaleList() {
            if (ulocales == null) {
                ulocales = createULocaleList(prefix, ICU_DATA_CLASS_LOADER);
            }
            return ulocales;
        }
        Locale[] getLocaleList() {
            if (locales == null) {
                locales = createLocaleList(prefix);
            }
            return locales;
        }
        Set getLocaleNameSet() {
            if (nameSet == null) {
                nameSet = createLocaleNameSet(prefix);
            }
            return nameSet;
        }
        Set getFullLocaleNameSet() {
            if (fullNameSet == null) {
                fullNameSet = createFullLocaleNameSet(prefix);
            }
            return fullNameSet;
        }
    }

    /**
     * Stores the locale information in a cache accessed by key (bundle prefix).
     * The cached objects are AvailEntries. The cache is held by a SoftReference
     * so it can be GC'd.
     */
    private static AvailEntry getAvailEntry(String key) {
        AvailEntry ae = null;
        Map lcache = null;
        if (GET_AVAILABLE_CACHE != null) {
            lcache = (Map) GET_AVAILABLE_CACHE.get();
            if (lcache != null) {
                ae = (AvailEntry) lcache.get(key);
            }
        }

        if (ae == null) {
            ae = new AvailEntry(key);
            if (lcache == null) {
                lcache = new HashMap();
                lcache.put(key, ae);
                GET_AVAILABLE_CACHE = new SoftReference(lcache);
            } else {
                lcache.put(key, ae);
            }
        }

        return ae;
    }

    protected static final ICUResourceBundle findResourceWithFallback(String path,
            UResourceBundle actualBundle, UResourceBundle requested) {
        ICUResourceBundle sub = null;
        if (requested == null) {
            requested = actualBundle;
        }
        while (actualBundle != null) {
            StringTokenizer st = new StringTokenizer(path, "/");
            ICUResourceBundle current = (ICUResourceBundle) actualBundle;
            while (st.hasMoreTokens()) {
                String subKey = st.nextToken();
                sub =  (ICUResourceBundle)current.handleGet(subKey, null, requested);
                if (sub == null) {
                    break;
                }
                current = sub;
            }
            if (sub != null) {
                //we found it
                break;
            }
            if (((ICUResourceBundle)actualBundle).resPath.length() != 0) {
                path = ((ICUResourceBundle)actualBundle).resPath + "/" + path;
            }
            // if not try the parent bundle
            actualBundle = ((ICUResourceBundle) actualBundle).getParent();

        }
        if(sub != null){
            sub.setLoadingStatus(((ICUResourceBundle)requested).getLocaleID());
        }
        return sub;
    }
    public boolean equals(Object other) {
        if (other instanceof ICUResourceBundle) {
            ICUResourceBundle o = (ICUResourceBundle) other;
            if (getBaseName().equals(o.getBaseName())
                    && getLocaleID().equals(o.getLocaleID())) {
                return true;
            }
        }
        return false;
    }
    // This method is for super class's instantiateBundle method
    public static UResourceBundle getBundleInstance(String baseName, String localeID,
                                                    ClassLoader root, boolean disableFallback){
        UResourceBundle b = instantiateBundle(baseName, localeID, root, disableFallback);
        if(b==null){
            throw new MissingResourceException("Could not find the bundle "+ baseName+"/"+ localeID+".res","","");
        }
        return b;
    }
    //  recursively build bundle .. over-ride super class method.
    protected synchronized static UResourceBundle instantiateBundle(String baseName, String localeID,
                                                                    ClassLoader root, boolean disableFallback){
        ULocale defaultLocale = ULocale.getDefault();
        String localeName = localeID;
        if(localeName.indexOf('@')>0){
            localeName = ULocale.getBaseName(localeID);
        }
        String fullName = ICUResourceBundleReader.getFullName(baseName, localeName);
        ICUResourceBundle b = (ICUResourceBundle)loadFromCache(root, fullName, defaultLocale);

        // here we assume that java type resource bundle organization
        // is required then the base name contains '.' else
        // the resource organization is of ICU type
        // so clients can instantiate resources of the type
        // com.mycompany.data.MyLocaleElements_en.res and
        // com.mycompany.data.MyLocaleElements.res
        //
        final String rootLocale = (baseName.indexOf('.')==-1) ? "root" : "";
        final String defaultID = ULocale.getDefault().toString();

        if(localeName.equals("")){
            localeName = rootLocale;
        }
        if(DEBUG) System.out.println("Creating "+fullName+ " currently b is "+b);
        if (b == null) {
            b = ICUResourceBundle.createBundle(baseName, localeName, root);

            if(DEBUG)System.out.println("The bundle created is: "+b+" and disableFallback="+disableFallback+" and bundle.getNoFallback="+(b!=null && b.getNoFallback()));
            if(disableFallback || (b!=null && b.getNoFallback())){
                addToCache(root, fullName, defaultLocale, b);
                // no fallback because the caller said so or because the bundle says so
                return b;
            }

            // fallback to locale ID parent
            if(b == null){
                int i = localeName.lastIndexOf('_');
                if (i != -1) {
                    String temp = localeName.substring(0, i);
                    b = (ICUResourceBundle)instantiateBundle(baseName, temp, root, disableFallback);
                    if(b!=null && b.getULocale().equals(temp)){
                        b.setLoadingStatus(ICUResourceBundle.FROM_FALLBACK);
                    }
                }else{
                    if(defaultID.indexOf(localeName)==-1){
                        b = (ICUResourceBundle)instantiateBundle(baseName, defaultID, root, disableFallback);
                        if(b!=null){
                            b.setLoadingStatus(ICUResourceBundle.FROM_DEFAULT);
                        }
                    }else if(rootLocale.length()!=0){
                        b = ICUResourceBundle.createBundle(baseName, rootLocale, root);
                        if(b!=null){
                            b.setLoadingStatus(ICUResourceBundle.FROM_ROOT);
                        }
                    }
                }
            }else{
                UResourceBundle parent = null;
                localeName = b.getLocaleID();
                int i = localeName.lastIndexOf('_');

                addToCache(root, fullName, defaultLocale, b);

                if (i != -1) {
                    parent = instantiateBundle(baseName, localeName.substring(0, i), root, disableFallback);
                }else if(!localeName.equals(rootLocale)){
                    parent = instantiateBundle(baseName, rootLocale, root, true);
                }

                if(!b.equals(parent)){
                    b.setParent(parent);
                }
            }
        }
        return b;
    }
    UResourceBundle get(String aKey, HashMap table, UResourceBundle requested) {
        ICUResourceBundle obj = (ICUResourceBundle)handleGet(aKey, table, requested);
        if (obj == null) {
            obj = (ICUResourceBundle)getParent();
            if (obj != null) {
                //call the get method to recursively fetch the resource
                obj = (ICUResourceBundle)obj.get(aKey, table, requested);
            }
            if (obj == null) {
                String fullName = ICUResourceBundleReader.getFullName(
                        getBaseName(), getLocaleID());
                throw new MissingResourceException(
                        "Can't find resource for bundle " + fullName + ", key "
                                + aKey, this.getClass().getName(), aKey);
            }
        }
        ((ICUResourceBundle)obj).setLoadingStatus(((ICUResourceBundle)requested).getLocaleID());
        return obj;
    }
    //protected byte[] version;
    protected byte[] rawData;
    protected long rootResource;
    protected boolean noFallback;

    protected String localeID;
    protected String baseName;
    protected ULocale ulocale;
    protected ClassLoader loader;

    //protected static final boolean ASSERT = false;

    /**
     *
     * @param baseName
     * @param localeID
     * @param root
     * @return the new bundle
     */
    public static ICUResourceBundle createBundle(String baseName,
            String localeID, ClassLoader root) {

        ICUResourceBundleReader reader = ICUResourceBundleReader.getReader( baseName, localeID, root);
        // could not open the .res file so return null
        if (reader == null) {
            return null;
        }
        return getBundle(reader, baseName, localeID, root);
    }

    protected String getLocaleID() {
        return localeID;
    }

    protected String getBaseName() {
        return baseName;
    }

    public ULocale getULocale() {
        return ulocale;
    }

    public UResourceBundle getParent() {
        return (UResourceBundle) parent;
    }

    protected void setParent(ResourceBundle parent) {
        this.parent = parent;
    }

    /**
     * Get the noFallback flag specified in the loaded bundle.
     * @return The noFallback flag.
     */
    protected boolean getNoFallback() {
        return noFallback;
    }

    private static ICUResourceBundle getBundle(ICUResourceBundleReader reader, String baseName, String localeID, ClassLoader loader) {

        long rootResource = (UNSIGNED_INT_MASK) & reader.getRootResource();

        int type = RES_GET_TYPE(rootResource);
        if (type == TABLE) {
            ICUResourceBundleImpl.ResourceTable table = new ICUResourceBundleImpl.ResourceTable(reader, baseName, localeID, loader);
            if(table.getSize()>=1){ // ticket#5683 ICU4J 3.6 data for zh_xx contains an entry other than %%ALIAS
                UResourceBundle b = table.handleGetImpl(0, null, table, null); // handleGet will cache the bundle with no parent set
                String itemKey = b.getKey();

                // %%ALIAS is such a hack!
                if (itemKey.equals("%%ALIAS")) {
                    String locale = b.getString();
                    UResourceBundle actual =  UResourceBundle.getBundleInstance(baseName, locale);
                    return (ICUResourceBundleImpl.ResourceTable) actual;
                }else{
                    return table;
                }
            }else {
                return table;
            }
        } else if (type == TABLE32) {

            // genrb does not generate Table32 with %%ALIAS
            return new ICUResourceBundleImpl.ResourceTable32(reader, baseName, localeID, loader);
        } else {
            throw new IllegalStateException("Invalid format error");
        }
    }
    // private constructor for inner classes
    protected ICUResourceBundle(){}

    public static final int RES_GET_TYPE(long res) {
        return (int) ((res) >> 28L);
    }
    protected static final int RES_GET_OFFSET(long res) {
        return (int) ((res & 0x0fffffff) << 2); // * 4
    }
    /* get signed and unsigned integer values directly from the Resource handle */
    protected static final int RES_GET_INT(long res) {
        return (((int) ((res) << 4)) >> 4);
    }
    static final long RES_GET_UINT(long res) {
        long t = ((res) & 0x0fffffffL);
        return t;
    }
    static final StringBuffer RES_GET_KEY(byte[] rawData,
            int keyOffset) {
        char ch;
        StringBuffer key = new StringBuffer();
        while ((ch = (char) rawData[keyOffset]) != 0) {
            key.append(ch);
            keyOffset++;
        }
        return key;
    }
    protected static final int getIntOffset(int offset) {
        return (offset << 2); // * 4
    }
    static final int getCharOffset(int offset) {
        return (offset << 1); // * 2
    }
    protected final ICUResourceBundle createBundleObject(String _key,
            long _resource, String _resPath, HashMap table,
            UResourceBundle requested, ICUResourceBundle bundle, boolean[] isAlias) {
        if (isAlias != null) {
            isAlias[0] = false;
        }
        //if (resource != RES_BOGUS) {
        switch (RES_GET_TYPE(_resource)) {
            case STRING : {
                return new ICUResourceBundleImpl.ResourceString(_key, _resPath, _resource, this);
            }
            case BINARY : {
                return new ICUResourceBundleImpl.ResourceBinary(_key, _resPath, _resource, this);
            }
            case ALIAS : {
                if (isAlias != null) {
                    isAlias[0] = true;
                }
                return findResource(_key, _resource, table, requested);
            }
            case INT : {
                return new ICUResourceBundleImpl.ResourceInt(_key, _resPath, _resource, this);
            }
            case INT_VECTOR : {
                return new ICUResourceBundleImpl.ResourceIntVector(_key, _resPath, _resource, this);
            }
            case ARRAY : {
                return new ICUResourceBundleImpl.ResourceArray(_key, _resPath, _resource, this);
            }
            case TABLE32 : {
                return new ICUResourceBundleImpl.ResourceTable32(_key, _resPath, _resource, this);
            }
            case TABLE : {
                return new ICUResourceBundleImpl.ResourceTable(_key, _resPath, _resource, this);
            }
            default :
                throw new IllegalStateException("The resource type is unknown");
        }
        //}
        //return null;
    }

    static final void assign(ICUResourceBundle b1, ICUResourceBundle b2){
        b1.rawData = b2.rawData;
        b1.rootResource = b2.rootResource;
        b1.noFallback = b2.noFallback;
        b1.baseName = b2.baseName;
        b1.localeID = b2.localeID;
        b1.ulocale = b2.ulocale;
        b1.loader = b2.loader;
        b1.parent = b2.parent;
    }

    int findKey(int siz, int currentOffset, ICUResourceBundle res, String target) {
        int mid = 0, start = 0, limit = siz;
        int lastMid = -1;

        int targetLength = target.length();
        char targetChar;
        char actualChar;
        int offset;

        //int myCharOffset = 0, keyOffset = 0;
        outer: for (;;) {
            mid = ((start + limit) >> 1); // compute average
            if (lastMid == mid) { /* Have we moved? */
                break; /* We haven't moved, and it wasn't found. */
            }
            lastMid = mid;

            offset = res.getOffset(currentOffset, mid);

            // compare a segment of rawData with targetArray
            for (int i=0; i<targetLength; i++) {
                targetChar = target.charAt(i);
                actualChar = (char)rawData[offset];
                if (actualChar == 0 || targetChar > actualChar ) {
                    // target > data
                    start = mid;
                    continue outer;
                }
                if (targetChar < actualChar) {
                    // target < data
                    limit = mid;
                    continue outer;
                }
                // target == data so far...
                offset++;
            }
            actualChar = (char)rawData[offset];
            if (actualChar != 0) {
                // target < data
                limit = mid;
                continue outer;
            }
            // target == data, we're sure now
            return mid;
        }
        return -1;
    }

    public int getOffset(int currentOfset, int index){
        return -1;
    }

    private static final char makeChar(byte[] data, int offset) {
        return (char)((data[offset++] << 8) | (data[offset] & 0xff));
    }
    static char getChar(byte[]data, int offset){
        return makeChar(data, offset);
    }
    private static final int makeInt(byte[] data, int offset) {
        // | is left-associative
        return (int) ((data[offset++] << 24) | ((data[offset++] & 0xff) << 16) | ((data[offset++] & 0xff) << 8) | ((data[offset] & 0xff)));
    }

    protected static int getInt(byte[] data, int offset){
        //if (ASSERT) Assert.assrt("offset < data.length", offset < data.length);
        return makeInt(data, offset);
    }

    String getStringValue(long res) {
        if (res == 0) {
            /*
             * The data structure is documented as supporting resource==0 for empty strings.
             * Return a fixed pointer in such a case.
             * This was dropped in uresdata.c 1.17 as part of Jitterbug 1005 work
             * on code coverage for ICU 2.0.
             * Re-added for consistency with the design and with other code.
             */
            return "";
        }
        int offset = RES_GET_OFFSET(res);
        int length = getInt(rawData,offset);
        int stringOffset = offset + getIntOffset(1);
        char[] dst = new char[length];
        //if (ASSERT) Assert.assrt("(stringOffset+getCharOffset(length)) < rawData.length", (stringOffset+getCharOffset(length)) < rawData.length);
        for(int i=0; i<length; i++){
            dst[i]=getChar(rawData, stringOffset+getCharOffset(i));
        }
        return new String(dst);
    }
    private static final char RES_PATH_SEP_CHAR = '/';
    private static final String RES_PATH_SEP_STR = "/";
    private static final String ICUDATA = "ICUDATA";
    private static final char HYPHEN = '-';
    private static final String LOCALE = "LOCALE";

    protected static final int getIndex(String s) {
        if (s.length() >= 1) {
            return Integer.valueOf(s).intValue();
        }
        return -1;
    }
    private ICUResourceBundle findResource(String _key, long _resource,
                                            HashMap table,
                                            UResourceBundle requested) {
        ClassLoader loaderToUse = loader;
        String locale = null, keyPath = null;
        String bundleName;
        String rpath = getStringValue(_resource);
        if (table == null) {
            table = new HashMap();
        }
        if (table.get(rpath) != null) {
            throw new IllegalArgumentException(
                    "Circular references in the resource bundles");
        }
        table.put(rpath, "");
        if (rpath.indexOf(RES_PATH_SEP_CHAR) == 0) {
            int i = rpath.indexOf(RES_PATH_SEP_CHAR, 1);
            int j = rpath.indexOf(RES_PATH_SEP_CHAR, i + 1);
            bundleName = rpath.substring(1, i);
            locale = rpath.substring(i + 1);
            if (j != -1) {
                locale = rpath.substring(i + 1, j);
                keyPath = rpath.substring(j + 1, rpath.length());
            }
            //there is a path included
            if (bundleName.equals(ICUDATA)) {
                bundleName = ICU_BASE_NAME;
                loaderToUse = ICU_DATA_CLASS_LOADER;
            }else if(bundleName.indexOf(ICUDATA)>-1){
                int idx = bundleName.indexOf(HYPHEN);
                if(idx>-1){
                    bundleName = ICU_BASE_NAME+RES_PATH_SEP_STR+bundleName.substring(idx+1,bundleName.length());
                    loaderToUse = ICU_DATA_CLASS_LOADER;
                }
            }
        } else {
            //no path start with locale
            int i = rpath.indexOf(RES_PATH_SEP_CHAR);
            keyPath = rpath.substring(i + 1);
            if (i != -1) {
                locale = rpath.substring(0, i);
            } else {
                locale = keyPath;
                keyPath = null;//keyPath.substring(i, keyPath.length());
            }
            bundleName = baseName;
        }
        ICUResourceBundle bundle = null;
        ICUResourceBundle sub = null;
        if(bundleName.equals(LOCALE)){
            bundleName = baseName;
            bundle = (ICUResourceBundle)requested;
            keyPath = rpath.substring(LOCALE.length() + 2/* prepending and appending / */, rpath.length());
            locale = ((ICUResourceBundle)requested).getLocaleID();
            sub = ICUResourceBundle.findResourceWithFallback(keyPath, requested, null);
            sub.resPath = "/" + sub.getLocaleID() + "/" + keyPath;
        }else{
            if (locale == null) {
                // {dlf} must use requestor's class loader to get resources from same jar
                bundle = (ICUResourceBundle) getBundleInstance(bundleName, "",
                         loaderToUse, false);
            } else {
                bundle = (ICUResourceBundle) getBundleInstance(bundleName, locale,
                         loaderToUse, false);
            }
            if (keyPath != null) {
                StringTokenizer st = new StringTokenizer(keyPath, "/");
                ICUResourceBundle current = bundle;
                while (st.hasMoreTokens()) {
                    String subKey = st.nextToken();
                    sub = (ICUResourceBundle)((ICUResourceBundle) current).get(subKey, table, requested);
                    if (sub == null) {
                        break;
                    }
                    current = sub;
                }
            } else {
                // if the sub resource is not found
                // try fetching the sub resource with
                // the key of this alias resource
                sub = (ICUResourceBundle)bundle.get(_key);
            }
            sub.resPath = rpath;
        }
        if (sub == null) {
            throw new MissingResourceException(localeID, baseName, _key);
        }
        return sub;
    }

    // Resource bundle lookup cache, which may be used by subclasses
    // which have nested resources
    protected ICUCache lookup;
    private static final int MAX_INITIAL_LOOKUP_SIZE = 64;

    protected void createLookupCache() {
        lookup = new SimpleCache(ICUCache.WEAK, Math.max(size*2, MAX_INITIAL_LOOKUP_SIZE));
    }

    protected UResourceBundle handleGet(String resKey, HashMap table, UResourceBundle requested) {
        UResourceBundle res = null;
        if (lookup != null) {
            res = (UResourceBundle)lookup.get(resKey);
        }
        if (res == null) {
            int[] index = new int[1];
            boolean[] alias = new boolean[1];
            res = handleGetImpl(resKey, table, requested, index, alias);
            if (res != null && lookup != null && !alias[0]) {
                // We do not want to cache a result from alias entry
                lookup.put(resKey, res);
                lookup.put(Utility.integerValueOf(index[0]), res);
            }
        }
        return res;
    }

    protected UResourceBundle handleGet(int index, HashMap table, UResourceBundle requested) {
        UResourceBundle res = null;
        Integer indexKey = null;
        if (lookup != null) {
            indexKey = Utility.integerValueOf(index);
            res = (UResourceBundle)lookup.get(indexKey);
        }
        if (res == null) {
            boolean[] alias = new boolean[1];
            res = handleGetImpl(index, table, requested, alias);
            if (res != null && lookup != null && !alias[0]) {
                // We do not want to cache a result from alias entry
                lookup.put(res.getKey(), res);
                lookup.put(indexKey, res);
            }
        }
        return res;
    }

    // Subclass which supports key based resource access to implement this method
    protected UResourceBundle handleGetImpl(String resKey, HashMap table, UResourceBundle requested,
            int[] index, boolean[] isAlias) {
        return null;
    }

    // Subclass which supports index based resource access to implement this method
    protected UResourceBundle handleGetImpl(int index, HashMap table, UResourceBundle requested,
            boolean[] isAlias) {
        return null;
    }
}