StandardCharsets.java

/*
 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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// -- This file was mechanically generated: Do not edit! -- //

package sun.nio.cs;

import java.nio.charset.Charset;
import java.nio.charset.spi.CharsetProvider;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import jdk.internal.vm.annotation.Stable;
import sun.security.action.GetPropertyAction;

// 标准"字符集"提供商，内部实现了与标准字符集相关的[规范名-别名-字符集类名-字符集实例]多重映射
public class StandardCharsets extends CharsetProvider {
    private static final String packagePrefix = "sun.nio.cs.";
    
    static String[] aliases_SJIS = new String[]{"sjis", "shift_jis", "shift-jis", "ms_kanji", "x-sjis", "csShiftJIS",};
    static String[] aliases_MS932 = new String[]{"MS932", "windows-932", "csWindows31J",};
    
    // StandardCharsets中三大映射
    @Stable
    private Map<String, String> classMap;       // [规范名-字符集类名]映射
    @Stable
    private Map<String, String> aliasMap;       // [别名-规范名]映射
    @Stable
    private Map<String, Charset> cache;         // [规范名-字符集实例]映射（初始时只包含常用实例）
    
    private boolean initialized = false;
    
    public StandardCharsets() {
    }
    
    
    
    /*▼ 返回相应的字符集别名 ████████████████████████████████████████████████████████████████████████████████┓ */
    
    static String[] aliases_US_ASCII() {
        return new String[]{"iso-ir-6", "ANSI_X3.4-1986", "ISO_646.irv:1991", "ASCII", "ISO646-US", "us", "IBM367", "cp367", "csASCII", "default", "646", "iso_646.irv:1983", "ANSI_X3.4-1968", "ascii7",};
    }
    
    static String[] aliases_UTF_8() {
        return new String[]{"UTF8", "unicode-1-1-utf-8",};
    }
    
    static String[] aliases_CESU_8() {
        return new String[]{"CESU8", "csCESU-8",};
    }
    
    static String[] aliases_UTF_16() {
        return new String[]{"UTF_16", "utf16", "unicode", "UnicodeBig",};
    }
    
    static String[] aliases_UTF_16BE() {
        return new String[]{"UTF_16BE", "ISO-10646-UCS-2", "X-UTF-16BE", "UnicodeBigUnmarked",};
    }
    
    static String[] aliases_UTF_16LE() {
        return new String[]{"UTF_16LE", "X-UTF-16LE", "UnicodeLittleUnmarked",};
    }
    
    static String[] aliases_UTF_16LE_BOM() {
        return new String[]{"UnicodeLittle",};
    }
    
    static String[] aliases_UTF_32() {
        return new String[]{"UTF_32", "UTF32",};
    }
    
    static String[] aliases_UTF_32LE() {
        return new String[]{"UTF_32LE", "X-UTF-32LE",};
    }
    
    static String[] aliases_UTF_32BE() {
        return new String[]{"UTF_32BE", "X-UTF-32BE",};
        
    }
    
    static String[] aliases_UTF_32LE_BOM() {
        return new String[]{"UTF_32LE_BOM", "UTF-32LE-BOM",};
    }
    
    static String[] aliases_UTF_32BE_BOM() {
        return new String[]{"UTF_32BE_BOM", "UTF-32BE-BOM",};
    }
    
    static String[] aliases_ISO_8859_1() {
        return new String[]{"iso-ir-100", "ISO_8859-1", "latin1", "l1", "IBM819", "cp819", "csISOLatin1", "819", "IBM-819", "ISO8859_1", "ISO_8859-1:1987", "ISO_8859_1", "8859_1", "ISO8859-1",};
    }
    
    static String[] aliases_ISO_8859_2() {
        return new String[]{"iso8859_2", "8859_2", "iso-ir-101", "ISO_8859-2", "ISO_8859-2:1987", "ISO8859-2", "latin2", "l2", "ibm912", "ibm-912", "cp912", "912", "csISOLatin2",};
    }
    
    static String[] aliases_ISO_8859_4() {
        return new String[]{"iso8859_4", "iso8859-4", "8859_4", "iso-ir-110", "ISO_8859-4", "ISO_8859-4:1988", "latin4", "l4", "ibm914", "ibm-914", "cp914", "914", "csISOLatin4",};
    }
    
    static String[] aliases_ISO_8859_5() {
        return new String[]{"iso8859_5", "8859_5", "iso-ir-144", "ISO_8859-5", "ISO_8859-5:1988", "ISO8859-5", "cyrillic", "ibm915", "ibm-915", "cp915", "915", "csISOLatinCyrillic",};
    }
    
    static String[] aliases_ISO_8859_7() {
        return new String[]{"iso8859_7", "8859_7", "iso-ir-126", "ISO_8859-7", "ISO_8859-7:1987", "ELOT_928", "ECMA-118", "greek", "greek8", "csISOLatinGreek", "sun_eu_greek", "ibm813", "ibm-813", "813", "cp813", "iso8859-7",};
    }
    
    static String[] aliases_ISO_8859_9() {
        return new String[]{"iso8859_9", "8859_9", "iso-ir-148", "ISO_8859-9", "ISO_8859-9:1989", "ISO8859-9", "latin5", "l5", "ibm920", "ibm-920", "920", "cp920", "csISOLatin5",};
    }
    
    static String[] aliases_ISO_8859_13() {
        return new String[]{"iso8859_13", "8859_13", "iso_8859-13", "ISO8859-13",};
    }
    
    static String[] aliases_ISO_8859_15() {
        return new String[]{"ISO_8859-15", "Latin-9", "csISO885915", "8859_15", "ISO-8859-15", "ISO8859_15", "ISO8859-15", "IBM923", "IBM-923", "cp923", "923", "LATIN0", "LATIN9", "L9", "csISOlatin0", "csISOlatin9", "ISO8859_15_FDIS",};
    }
    
    static String[] aliases_ISO_8859_16() {
        return new String[]{"iso-ir-226", "ISO_8859-16:2001", "ISO_8859-16", "latin10", "l10", "csISO885916",};
    }
    
    static String[] aliases_KOI8_R() {
        return new String[]{"koi8_r", "koi8", "cskoi8r",};
    }
    
    static String[] aliases_KOI8_U() {
        return new String[]{"koi8_u",};
    }
    
    static String[] aliases_MS1250() {
        return new String[]{"cp1250", "cp5346",};
    }
    
    static String[] aliases_MS1251() {
        return new String[]{"cp1251", "cp5347", "ansi-1251",};
    }
    
    static String[] aliases_MS1252() {
        return new String[]{"cp1252", "cp5348", "ibm-1252", "ibm1252",};
    }
    
    static String[] aliases_MS1253() {
        return new String[]{"cp1253", "cp5349",};
    }
    
    static String[] aliases_MS1254() {
        return new String[]{"cp1254", "cp5350",};
    }
    
    static String[] aliases_MS1257() {
        return new String[]{"cp1257", "cp5353",};
    }
    
    static String[] aliases_IBM437() {
        return new String[]{"cp437", "ibm437", "ibm-437", "437", "cspc8codepage437", "windows-437",};
    }
    
    static String[] aliases_IBM737() {
        return new String[]{"cp737", "ibm737", "ibm-737", "737",};
    }
    
    static String[] aliases_IBM775() {
        return new String[]{"cp775", "ibm775", "ibm-775", "775",};
    }
    
    static String[] aliases_IBM850() {
        return new String[]{"cp850", "ibm-850", "ibm850", "850", "cspc850multilingual",};
    }
    
    static String[] aliases_IBM852() {
        return new String[]{"cp852", "ibm852", "ibm-852", "852", "csPCp852",};
    }
    
    static String[] aliases_IBM855() {
        return new String[]{"cp855", "ibm-855", "ibm855", "855", "cspcp855",};
    }
    
    static String[] aliases_IBM857() {
        return new String[]{"cp857", "ibm857", "ibm-857", "857", "csIBM857",};
    }
    
    static String[] aliases_IBM858() {
        return new String[]{"cp858", "ccsid00858", "cp00858", "858", "PC-Multilingual-850+euro",};
    }
    
    static String[] aliases_IBM862() {
        return new String[]{"cp862", "ibm862", "ibm-862", "862", "csIBM862", "cspc862latinhebrew",};
    }
    
    static String[] aliases_IBM866() {
        return new String[]{"cp866", "ibm866", "ibm-866", "866", "csIBM866",};
    }
    
    static String[] aliases_IBM874() {
        return new String[]{"cp874", "ibm874", "ibm-874", "874",};
    }
    
    static String[] aliases_MS950_HKSCS_XP() {
        return new String[]{"MS950_HKSCS_XP",};
    }
    
    static String[] aliases_MS950_HKSCS() {
        return new String[]{"MS950_HKSCS",};
    }
    
    static String[] aliases_MS950() {
        return new String[]{"ms950", "windows-950",};
    }
    
    static String[] aliases_MS874() {
        return new String[]{"ms874", "ms-874", "windows-874",};
    }
    
    static String[] aliases_GBK() {
        return new String[]{"windows-936", "CP936",};
    }
    
    static String[] aliases_MS936() {
        return new String[]{"ms936", "ms_936",};
    }
    
    static String[] aliases_SJIS() {
        return aliases_SJIS;
    }
    
    static String[] aliases_MS932() {
        return aliases_MS932;
    }
    
    static String[] aliases_JIS_X_0201() {
        return new String[]{"JIS0201", "JIS_X0201", "X0201", "csHalfWidthKatakana",};
    }
    
    static String[] aliases_MS949() {
        return new String[]{"ms949", "windows949", "windows-949", "ms_949",};
    }
    
    static String[] aliases_Johab() {
        return new String[]{"ksc5601-1992", "ksc5601_1992", "ms1361", "johab",};
    }
    
    static String[] aliases_MS1255() {
        return new String[]{"cp1255",};
    }
    
    static String[] aliases_MS1256() {
        return new String[]{"cp1256",};
    }
    
    static String[] aliases_MS1258() {
        return new String[]{"cp1258",};
    }
    
    /*▲ 返回相应的字符集别名 ████████████████████████████████████████████████████████████████████████████████┛ */
    
    
    // 将字符集名称转为小写。专用于ASCII的版本，针对启动期间的解析进行了优化
    private static String toLower(String s) {
        int n = s.length();
        
        boolean allLower = true;
        
        // 判断该名称s是否为纯小写形式
        for(int i = 0; i < n; i++) {
            int c = s.charAt(i);
            if(((c - 'A') | ('Z' - c)) >= 0) {
                allLower = false;
                break;
            }
        }
        if(allLower){
            return s;
        }
        
        StringBuilder sb = new StringBuilder(n);
        for(int i = 0; i < n; i++) {
            int c = s.charAt(i);
            if(((c - 'A') | ('Z' - c)) >= 0)
                sb.append((char) (c + 0x20));
            else
                sb.append((char) c);
        }
        return sb.toString();
    }
    
    // 通过给定的字符集名称，查找相应的字符集
    public final Charset charsetForName(String charsetName) {
        synchronized(this) {
            return lookup(charsetName);
        }
    }
    
    // 返回一个迭代器，用来让外部程序访问标准字符集。
    public final Iterator<Charset> charsets() {
        Set<String> charsetNames;
        
        // 创建StandardCharsets中三大映射，确保在synchronized中初始化
        synchronized(this) {
            init();
            // 返回[规范名-字符集类名]映射中的规范名集合
            charsetNames = classMap().keySet();
            aliasMap();
            cache();
        }
        
        return new Iterator<>() {
            // 包装了字符集规范名集合的迭代器
            Iterator<String> it = charsetNames.iterator();
            
            // true：存在下一个规范名
            public boolean hasNext() {
                return it.hasNext();
            }
            
            // 返回下一个规范名对应的字符集实例
            public Charset next() {
                String csn = it.next();
                return lookup(csn);
            }
            
            // 此处不支持移除
            public void remove() {
                throw new UnsupportedOperationException();
            }
        };
    }
    
    /*
     * 在[别名-规范名]映射系统中查找字符集名称，并将字符集名称规范化
     * 如果找到了别名对于的规范名，则返回规范名
     * 否则，返回这个别名（可能是个错误的名字，后面还需要继续判断）
     */
    private String canonicalize(String csn) {
        String acn = aliasMap().get(csn);
        return (acn != null) ? acn : csn;
    }
    
    // 返回/新建[别名-规范名]映射系统
    private Map<String, String> aliasMap() {
        Map<String, String> map = aliasMap;
        if(map == null) {
            aliasMap = map = new Aliases();
        }
        return map;
    }
    
    // 返回/新建[规范名-字符集类名]映射系统
    private Map<String, String> classMap() {
        Map<String, String> map = classMap;
        if(map == null) {
            classMap = map = new Classes();
        }
        return map;
    }
    
    // 返回/新建[规范名-字符集实例]映射（初始时只包含常用实例）系统
    private Map<String, Charset> cache() {
        Map<String, Charset> map = cache;
        if(map == null) {
            map = new Cache();
            map.put("utf-8", UTF_8.INSTANCE);
            map.put("iso-8859-1", ISO_8859_1.INSTANCE);
            map.put("us-ascii", US_ASCII.INSTANCE);
            map.put("utf-16", java.nio.charset.StandardCharsets.UTF_16);
            map.put("utf-16be", java.nio.charset.StandardCharsets.UTF_16BE);
            map.put("utf-16le", java.nio.charset.StandardCharsets.UTF_16LE);
            cache = map;
        }
        return map;
    }
    
    // 返回指定名称的字符集实例，如果不支持该字符集，返回null
    private Charset lookup(String charsetName) {
        init();
        
        // By checking these built-ins we can avoid initializing Aliases,
        // Classes and Cache eagerly during bootstrap.
        //
        // Initialization of java.nio.charset.StandardCharsets should be avoided here to minimize time spent in System.initPhase1,
        // as it may delay initialization of performance critical VM subsystems.
        String csn;
        
        // 先尝试通过常用标准名称"UTF-8"、"US-ASCII"、"ISO-8859-1"查找这几个缓存，没有的话，再到别名系统中去查找
        switch(charsetName) {
            case "UTF-8":
                return UTF_8.INSTANCE;
            case "US-ASCII":
                return US_ASCII.INSTANCE;
            case "ISO-8859-1":
                return ISO_8859_1.INSTANCE;
            default:
                // 考虑输入的是不是别名，所以去[别名-规范名]映射系统中查找字符集名称（先转为小写），并将字符集名称规范化
                csn = canonicalize(toLower(charsetName));
                break;
        }
        
        // 在[规范名-字符集实例]映射（初始时只包含常用实例）系统中查找字符集实例
        Charset cs = cache().get(csn);
        if(cs != null)
            return cs;
        
        /* 如果还没找到，就得看是否支持这种字符集了 */
        
        // 在[规范名-字符集类名]映射系统中查找是否存在该规范名对应的类
        String cln = classMap().get(csn);
        if(cln == null)
            return null;
        
        // 实例化该字符集，并将其放入[规范名-字符集实例]映射（初始时只包含常用实例）系统
        try {
            @SuppressWarnings("deprecation")
            Object o = Class.forName(packagePrefix + cln, true, this.getClass().getClassLoader()).newInstance();
            return cache(csn, (Charset) o);
        } catch(ClassNotFoundException | IllegalAccessException | InstantiationException x) {
            return null;
        }
        
        // 无论在哪一步找到字符集都将其返回，否则就返回null
    }
    
    // 缓存规范名csn的字符集cs，到[规范名-字符集实例]映射（初始时只包含常用实例）系统
    private Charset cache(String csn, Charset cs) {
        cache().put(csn, cs);
        return cs;
    }
    
    /**
     * provider the sun.nio.cs.map property fir sjis/ms932 mapping hack
     */
    // 尝试从sun.nio.cs.map属性中加载系统支持的字符集
    private void init() {
        // StandardCharsets已初始化
        if(initialized)
            return;
        
        // 虚拟机已初始化
        if(!jdk.internal.misc.VM.isBooted())
            return;
        
        initialized = true;
        
        String map = GetPropertyAction.privilegedGetProperty("sun.nio.cs.map");
        if(map != null) {
            Map<String, String> aliasMap = aliasMap();
            Map<String, String> classMap = classMap();
            String[] maps = map.split(",");
            for(String m : maps) {
                if(m.equalsIgnoreCase("Windows-31J/Shift_JIS")) {
                    // if we dont have both sjis and ms932, do nothing
                    if(classMap.get("shift_jis") == null || classMap.get("windows-31j") == null) {
                        break;
                    }
                    aliases_MS932 = new String[]{"MS932",        // JDK historical
                        "windows-932", "csWindows31J", "shift-jis", "ms_kanji", "x-sjis", "csShiftJIS",
                        // This alias takes precedence over the actual
                        // Shift_JIS charset itself since aliases are always resolved first, before looking up canonical names.
                        "shift_jis"};
                    aliases_SJIS = new String[]{"sjis"};
            
                    for(String alias : aliases_MS932) {
                        aliasMap.put(toLower(alias), "windows-31j");
                    }
                    cache().put("shift_jis", null);
                    break;
                }
            }
        }
    }
    
    // [别名-规范名]映射系统
    private static final class Aliases extends sun.util.PreHashedMap<String> {
        
        private static final int ROWS = 1024;
        private static final int SIZE = 256;
        private static final int SHIFT = 0;
        private static final int MASK = 0x3ff;
        
        private Aliases() {
            super(ROWS, SIZE, SHIFT, MASK);
        }
        
        protected void init(Object[] ht) {
            ht[1] = new Object[]{"csisolatin0", "iso-8859-15"};
            ht[2] = new Object[]{"csisolatin1", "iso-8859-1"};
            ht[3] = new Object[]{"csisolatin2", "iso-8859-2"};
            ht[5] = new Object[]{"csisolatin4", "iso-8859-4"};
            ht[6] = new Object[]{"csisolatin5", "iso-8859-9"};
            ht[10] = new Object[]{"csisolatin9", "iso-8859-15"};
            ht[19] = new Object[]{"unicodelittle", "x-utf-16le-bom"};
            ht[24] = new Object[]{"iso646-us", "us-ascii"};
            ht[25] = new Object[]{"iso_8859-7:1987", "iso-8859-7"};
            ht[26] = new Object[]{"912", "iso-8859-2"};
            ht[28] = new Object[]{"914", "iso-8859-4"};
            ht[29] = new Object[]{"915", "iso-8859-5"};
            ht[35] = new Object[]{"latin10", "iso-8859-16"};
            ht[49] = new Object[]{"ksc5601-1992", "x-johab"};
            ht[55] = new Object[]{"ibm-1252", "windows-1252", new Object[]{"920", "iso-8859-9"}};
            ht[58] = new Object[]{"923", "iso-8859-15"};
            ht[86] = new Object[]{"csisolatincyrillic", "iso-8859-5", new Object[]{"8859_1", "iso-8859-1"}};
            ht[87] = new Object[]{"8859_2", "iso-8859-2"};
            ht[89] = new Object[]{"8859_4", "iso-8859-4"};
            ht[90] = new Object[]{"813", "iso-8859-7", new Object[]{"8859_5", "iso-8859-5"}};
            ht[92] = new Object[]{"8859_7", "iso-8859-7"};
            ht[94] = new Object[]{"8859_9", "iso-8859-9"};
            ht[95] = new Object[]{"iso_8859-1:1987", "iso-8859-1"};
            ht[96] = new Object[]{"819", "iso-8859-1"};
            ht[106] = new Object[]{"unicode-1-1-utf-8", "utf-8"};
            ht[110] = new Object[]{"ms-874", "x-windows-874"};
            ht[121] = new Object[]{"x-utf-16le", "utf-16le"};
            ht[125] = new Object[]{"ecma-118", "iso-8859-7"};
            ht[134] = new Object[]{"koi8_r", "koi8-r"};
            ht[137] = new Object[]{"koi8_u", "koi8-u"};
            ht[141] = new Object[]{"cp912", "iso-8859-2"};
            ht[143] = new Object[]{"cp914", "iso-8859-4"};
            ht[144] = new Object[]{"cp915", "iso-8859-5"};
            ht[151] = new Object[]{"jis0201", "jis_x0201"};
            ht[170] = new Object[]{"cp920", "iso-8859-9"};
            ht[173] = new Object[]{"cp923", "iso-8859-15"};
            ht[177] = new Object[]{"utf_32le_bom", "x-utf-32le-bom"};
            ht[192] = new Object[]{"utf_16be", "utf-16be"};
            ht[199] = new Object[]{"cspc8codepage437", "ibm437", new Object[]{"ansi-1251", "windows-1251"}};
            ht[205] = new Object[]{"cp813", "iso-8859-7"};
            ht[207] = new Object[]{"cp936", "gbk"};
            ht[211] = new Object[]{"850", "ibm850", new Object[]{"cp819", "iso-8859-1"}};
            ht[213] = new Object[]{"852", "ibm852"};
            ht[216] = new Object[]{"855", "ibm855"};
            ht[217] = new Object[]{"cswindows31j", "windows-31j"};
            ht[218] = new Object[]{"857", "ibm857", new Object[]{"iso-ir-6", "us-ascii"}};
            ht[219] = new Object[]{"858", "ibm00858", new Object[]{"737", "x-ibm737"}};
            ht[225] = new Object[]{"csascii", "us-ascii"};
            ht[242] = new Object[]{"ms932", "windows-31j", new Object[]{"ibm1252", "windows-1252"}};
            ht[244] = new Object[]{"862", "ibm862"};
            ht[246] = new Object[]{"ms936", "x-mswin-936"};
            ht[248] = new Object[]{"866", "ibm866"};
            ht[253] = new Object[]{"x-utf-32be", "utf-32be"};
            ht[254] = new Object[]{"iso_8859-2:1987", "iso-8859-2"};
            ht[259] = new Object[]{"unicodebig", "utf-16"};
            ht[269] = new Object[]{"iso8859_15_fdis", "iso-8859-15"};
            ht[277] = new Object[]{"874", "x-ibm874"};
            ht[280] = new Object[]{"ms949", "x-windows-949", new Object[]{"unicodelittleunmarked", "utf-16le"}};
            ht[283] = new Object[]{"iso8859_1", "iso-8859-1"};
            ht[284] = new Object[]{"iso8859_2", "iso-8859-2"};
            ht[285] = new Object[]{"csiso885915", "iso-8859-15"};
            ht[286] = new Object[]{"csiso885916", "iso-8859-16", new Object[]{"iso8859_4", "iso-8859-4"}};
            ht[287] = new Object[]{"iso8859_5", "iso-8859-5"};
            ht[289] = new Object[]{"iso8859_7", "iso-8859-7"};
            ht[291] = new Object[]{"iso8859_9", "iso-8859-9"};
            ht[294] = new Object[]{"ibm912", "iso-8859-2"};
            ht[296] = new Object[]{"ibm914", "iso-8859-4"};
            ht[297] = new Object[]{"ibm915", "iso-8859-5"};
            ht[302] = new Object[]{"ms950", "x-windows-950"};
            ht[305] = new Object[]{"iso_8859-13", "iso-8859-13"};
            ht[307] = new Object[]{"iso_8859-15", "iso-8859-15"};
            ht[308] = new Object[]{"iso_8859-16", "iso-8859-16"};
            ht[312] = new Object[]{"greek8", "iso-8859-7", new Object[]{"646", "us-ascii"}};
            ht[318] = new Object[]{"ms_kanji", "shift_jis"};
            ht[321] = new Object[]{"ibm-912", "iso-8859-2"};
            ht[323] = new Object[]{"ibm920", "iso-8859-9", new Object[]{"ibm-914", "iso-8859-4"}};
            ht[324] = new Object[]{"ibm-915", "iso-8859-5"};
            ht[325] = new Object[]{"l1", "iso-8859-1"};
            ht[326] = new Object[]{"cp850", "ibm850", new Object[]{"ibm923", "iso-8859-15", new Object[]{"l2", "iso-8859-2"}}};
            ht[327] = new Object[]{"cyrillic", "iso-8859-5"};
            ht[328] = new Object[]{"cp852", "ibm852", new Object[]{"l4", "iso-8859-4"}};
            ht[329] = new Object[]{"l5", "iso-8859-9"};
            ht[331] = new Object[]{"cp855", "ibm855"};
            ht[333] = new Object[]{"cp857", "ibm857", new Object[]{"l9", "iso-8859-15"}};
            ht[334] = new Object[]{"cp858", "ibm00858", new Object[]{"cp737", "x-ibm737"}};
            ht[336] = new Object[]{"iso_8859_1", "iso-8859-1"};
            ht[339] = new Object[]{"koi8", "koi8-r"};
            ht[341] = new Object[]{"775", "ibm775"};
            ht[345] = new Object[]{"iso_8859-9:1989", "iso-8859-9"};
            ht[350] = new Object[]{"ibm-920", "iso-8859-9"};
            ht[353] = new Object[]{"ibm-923", "iso-8859-15"};
            ht[358] = new Object[]{"ibm813", "iso-8859-7"};
            ht[359] = new Object[]{"cp862", "ibm862"};
            ht[363] = new Object[]{"cp866", "ibm866"};
            ht[364] = new Object[]{"ibm819", "iso-8859-1"};
            ht[378] = new Object[]{"ansi_x3.4-1968", "us-ascii"};
            ht[385] = new Object[]{"ibm-813", "iso-8859-7"};
            ht[391] = new Object[]{"ibm-819", "iso-8859-1"};
            ht[392] = new Object[]{"cp874", "x-ibm874"};
            ht[405] = new Object[]{"iso-ir-100", "iso-8859-1"};
            ht[406] = new Object[]{"iso-ir-101", "iso-8859-2"};
            ht[408] = new Object[]{"437", "ibm437"};
            ht[410] = new Object[]{"iso-ir-226", "iso-8859-16"};
            ht[421] = new Object[]{"iso-8859-15", "iso-8859-15"};
            ht[428] = new Object[]{"latin0", "iso-8859-15"};
            ht[429] = new Object[]{"latin1", "iso-8859-1"};
            ht[430] = new Object[]{"latin2", "iso-8859-2"};
            ht[431] = new Object[]{"ms874", "x-windows-874"};
            ht[432] = new Object[]{"latin4", "iso-8859-4"};
            ht[433] = new Object[]{"latin5", "iso-8859-9"};
            ht[436] = new Object[]{"iso-ir-110", "iso-8859-4"};
            ht[437] = new Object[]{"latin9", "iso-8859-15"};
            ht[438] = new Object[]{"ansi_x3.4-1986", "us-ascii"};
            ht[443] = new Object[]{"utf-32be-bom", "x-utf-32be-bom"};
            ht[449] = new Object[]{"sjis", "shift_jis"};
            ht[456] = new Object[]{"cp775", "ibm775"};
            ht[471] = new Object[]{"shift_jis", "shift_jis"};
            ht[473] = new Object[]{"iso-ir-126", "iso-8859-7"};
            ht[479] = new Object[]{"ibm850", "ibm850"};
            ht[481] = new Object[]{"ibm852", "ibm852"};
            ht[484] = new Object[]{"ibm855", "ibm855"};
            ht[486] = new Object[]{"ibm857", "ibm857"};
            ht[487] = new Object[]{"ibm737", "x-ibm737"};
            ht[495] = new Object[]{"ms950_hkscs", "x-ms950-hkscs"};
            ht[502] = new Object[]{"x-sjis", "shift_jis", new Object[]{"utf_16le", "utf-16le"}};
            ht[506] = new Object[]{"ibm-850", "ibm850"};
            ht[508] = new Object[]{"ibm-852", "ibm852"};
            ht[511] = new Object[]{"ibm-855", "ibm855"};
            ht[512] = new Object[]{"ibm862", "ibm862"};
            ht[513] = new Object[]{"ibm-857", "ibm857"};
            ht[514] = new Object[]{"ibm-737", "x-ibm737"};
            ht[516] = new Object[]{"ibm866", "ibm866"};
            ht[520] = new Object[]{"unicodebigunmarked", "utf-16be"};
            ht[523] = new Object[]{"cp437", "ibm437"};
            ht[524] = new Object[]{"utf16", "utf-16"};
            ht[526] = new Object[]{"windows-932", "windows-31j"};
            ht[530] = new Object[]{"windows-936", "gbk"};
            ht[533] = new Object[]{"iso-ir-144", "iso-8859-5"};
            ht[537] = new Object[]{"iso-ir-148", "iso-8859-9"};
            ht[539] = new Object[]{"ibm-862", "ibm862"};
            ht[543] = new Object[]{"ibm-866", "ibm866"};
            ht[545] = new Object[]{"ibm874", "x-ibm874"};
            ht[563] = new Object[]{"x-utf-32le", "utf-32le"};
            ht[564] = new Object[]{"windows-949", "x-windows-949"};
            ht[572] = new Object[]{"ibm-874", "x-ibm874"};
            ht[573] = new Object[]{"iso_8859-4:1988", "iso-8859-4"};
            ht[577] = new Object[]{"default", "us-ascii"};
            ht[579] = new Object[]{"ms_936", "x-mswin-936"};
            ht[582] = new Object[]{"utf32", "utf-32"};
            ht[583] = new Object[]{"pc-multilingual-850+euro", "ibm00858"};
            ht[586] = new Object[]{"windows-950", "x-windows-950"};
            ht[588] = new Object[]{"elot_928", "iso-8859-7"};
            ht[591] = new Object[]{"cshalfwidthkatakana", "jis_x0201"};
            ht[593] = new Object[]{"csisolatingreek", "iso-8859-7"};
            ht[598] = new Object[]{"csibm857", "ibm857"};
            ht[609] = new Object[]{"ibm775", "ibm775"};
            ht[613] = new Object[]{"ms_949", "x-windows-949"};
            ht[617] = new Object[]{"cp1250", "windows-1250"};
            ht[618] = new Object[]{"cp1251", "windows-1251"};
            ht[619] = new Object[]{"cp1252", "windows-1252"};
            ht[620] = new Object[]{"cp1253", "windows-1253"};
            ht[621] = new Object[]{"cp1254", "windows-1254"};
            ht[622] = new Object[]{"cp1255", "windows-1255"};
            ht[623] = new Object[]{"cp1256", "windows-1256"};
            ht[624] = new Object[]{"csibm862", "ibm862", new Object[]{"cp1257", "windows-1257"}};
            ht[625] = new Object[]{"cp1258", "windows-1258"};
            ht[628] = new Object[]{"csibm866", "ibm866", new Object[]{"cesu8", "cesu-8"}};
            ht[632] = new Object[]{"iso8859_13", "iso-8859-13"};
            ht[634] = new Object[]{"iso8859_15", "iso-8859-15", new Object[]{"utf_32be", "utf-32be"}};
            ht[635] = new Object[]{"utf_32be_bom", "x-utf-32be-bom"};
            ht[636] = new Object[]{"ibm-775", "ibm775"};
            ht[654] = new Object[]{"cp00858", "ibm00858"};
            ht[669] = new Object[]{"8859_13", "iso-8859-13"};
            ht[670] = new Object[]{"us", "us-ascii"};
            ht[671] = new Object[]{"8859_15", "iso-8859-15"};
            ht[676] = new Object[]{"ibm437", "ibm437"};
            ht[679] = new Object[]{"cp367", "us-ascii"};
            ht[686] = new Object[]{"iso-10646-ucs-2", "utf-16be"};
            ht[703] = new Object[]{"ibm-437", "ibm437"};
            ht[710] = new Object[]{"iso8859-13", "iso-8859-13"};
            ht[712] = new Object[]{"iso8859-15", "iso-8859-15"};
            ht[715] = new Object[]{"windows-874", "x-windows-874"};
            ht[732] = new Object[]{"iso_8859-5:1988", "iso-8859-5"};
            ht[733] = new Object[]{"unicode", "utf-16"};
            ht[768] = new Object[]{"greek", "iso-8859-7"};
            ht[771] = new Object[]{"ms1361", "x-johab"};
            ht[774] = new Object[]{"ascii7", "us-ascii"};
            ht[781] = new Object[]{"iso8859-1", "iso-8859-1"};
            ht[782] = new Object[]{"iso8859-2", "iso-8859-2"};
            ht[783] = new Object[]{"cskoi8r", "koi8-r"};
            ht[784] = new Object[]{"jis_x0201", "jis_x0201", new Object[]{"iso8859-4", "iso-8859-4"}};
            ht[785] = new Object[]{"iso8859-5", "iso-8859-5"};
            ht[787] = new Object[]{"iso8859-7", "iso-8859-7"};
            ht[789] = new Object[]{"iso8859-9", "iso-8859-9"};
            ht[795] = new Object[]{"windows949", "x-windows-949"};
            ht[804] = new Object[]{"johab", "x-johab"};
            ht[813] = new Object[]{"ccsid00858", "ibm00858"};
            ht[818] = new Object[]{"cspc862latinhebrew", "ibm862"};
            ht[832] = new Object[]{"ibm367", "us-ascii"};
            ht[834] = new Object[]{"iso_8859-1", "iso-8859-1"};
            ht[835] = new Object[]{"iso_8859-2", "iso-8859-2", new Object[]{"x-utf-16be", "utf-16be"}};
            ht[836] = new Object[]{"sun_eu_greek", "iso-8859-7"};
            ht[837] = new Object[]{"iso_8859-16:2001", "iso-8859-16", new Object[]{"iso_8859-4", "iso-8859-4"}};
            ht[838] = new Object[]{"iso_8859-5", "iso-8859-5"};
            ht[840] = new Object[]{"ms950_hkscs_xp", "x-ms950-hkscs-xp", new Object[]{"cspcp852", "ibm852", new Object[]{"iso_8859-7", "iso-8859-7"}}};
            ht[841] = new Object[]{"shift-jis", "shift_jis"};
            ht[842] = new Object[]{"iso_8859-9", "iso-8859-9"};
            ht[843] = new Object[]{"cspcp855", "ibm855"};
            ht[846] = new Object[]{"windows-437", "ibm437"};
            ht[849] = new Object[]{"ascii", "us-ascii"};
            ht[863] = new Object[]{"cscesu-8", "cesu-8"};
            ht[867] = new Object[]{"ksc5601_1992", "x-johab"};
            ht[881] = new Object[]{"utf8", "utf-8"};
            ht[896] = new Object[]{"iso_646.irv:1983", "us-ascii"};
            ht[907] = new Object[]{"l10", "iso-8859-16"};
            ht[909] = new Object[]{"cp5346", "windows-1250"};
            ht[910] = new Object[]{"cp5347", "windows-1251"};
            ht[911] = new Object[]{"cp5348", "windows-1252"};
            ht[912] = new Object[]{"cp5349", "windows-1253"};
            ht[925] = new Object[]{"iso_646.irv:1991", "us-ascii"};
            ht[934] = new Object[]{"cp5350", "windows-1254"};
            ht[937] = new Object[]{"cp5353", "windows-1257"};
            ht[944] = new Object[]{"latin-9", "iso-8859-15", new Object[]{"utf_32le", "utf-32le"}};
            ht[957] = new Object[]{"utf_16", "utf-16"};
            ht[962] = new Object[]{"csshiftjis", "shift_jis"};
            ht[993] = new Object[]{"cspc850multilingual", "ibm850"};
            ht[1009] = new Object[]{"utf-32le-bom", "x-utf-32le-bom"};
            ht[1015] = new Object[]{"utf_32", "utf-32"};
            ht[1019] = new Object[]{"x0201", "jis_x0201"};
        }
    }
    
    // [规范名-字符集类名]映射
    private static final class Classes extends sun.util.PreHashedMap<String> {
        
        private static final int ROWS = 64;
        private static final int SIZE = 54;
        private static final int SHIFT = 0;
        private static final int MASK = 0x3f;
        
        private Classes() {
            super(ROWS, SIZE, SHIFT, MASK);
        }
        
        protected void init(Object[] ht) {
            ht[0] = new Object[]{"ibm862", "IBM862"};
            ht[2] = new Object[]{"windows-31j", "MS932"};
            ht[4] = new Object[]{"ibm866", "IBM866", new Object[]{"utf-16le", "UTF_16LE"}};
            ht[5] = new Object[]{"utf-32", "UTF_32"};
            ht[6] = new Object[]{"windows-1250", "MS1250"};
            ht[7] = new Object[]{"windows-1251", "MS1251"};
            ht[8] = new Object[]{"windows-1252", "MS1252", new Object[]{"utf-32be", "UTF_32BE"}};
            ht[9] = new Object[]{"windows-1253", "MS1253"};
            ht[10] = new Object[]{"windows-1254", "MS1254"};
            ht[11] = new Object[]{"windows-1255", "MS1255", new Object[]{"utf-16", "UTF_16"}};
            ht[12] = new Object[]{"windows-1256", "MS1256", new Object[]{"x-ms950-hkscs", "MS950_HKSCS"}};
            ht[13] = new Object[]{"windows-1257", "MS1257"};
            ht[14] = new Object[]{"windows-1258", "MS1258", new Object[]{"utf-16be", "UTF_16BE"}};
            ht[15] = new Object[]{"x-johab", "Johab"};
            ht[16] = new Object[]{"jis_x0201", "JIS_X_0201", new Object[]{"iso-8859-1", "ISO_8859_1"}};
            ht[17] = new Object[]{"iso-8859-2", "ISO_8859_2"};
            ht[18] = new Object[]{"utf-8", "UTF_8"};
            ht[19] = new Object[]{"iso-8859-4", "ISO_8859_4"};
            ht[20] = new Object[]{"iso-8859-5", "ISO_8859_5"};
            ht[22] = new Object[]{"x-ibm874", "IBM874", new Object[]{"iso-8859-7", "ISO_8859_7"}};
            ht[23] = new Object[]{"shift_jis", "SJIS"};
            ht[24] = new Object[]{"iso-8859-9", "ISO_8859_9"};
            ht[25] = new Object[]{"x-ms950-hkscs-xp", "MS950_HKSCS_XP"};
            ht[28] = new Object[]{"x-ibm737", "IBM737"};
            ht[31] = new Object[]{"x-windows-949", "MS949", new Object[]{"ibm850", "IBM850"}};
            ht[33] = new Object[]{"ibm852", "IBM852", new Object[]{"ibm775", "IBM775"}};
            ht[34] = new Object[]{"us-ascii", "US_ASCII"};
            ht[35] = new Object[]{"iso-8859-13", "ISO_8859_13"};
            ht[36] = new Object[]{"ibm855", "IBM855", new Object[]{"ibm437", "IBM437"}};
            ht[37] = new Object[]{"iso-8859-15", "ISO_8859_15"};
            ht[38] = new Object[]{"ibm857", "IBM857", new Object[]{"iso-8859-16", "ISO_8859_16", new Object[]{"x-utf-32le-bom", "UTF_32LE_BOM"}}};
            ht[39] = new Object[]{"ibm00858", "IBM858"};
            ht[44] = new Object[]{"x-utf-16le-bom", "UTF_16LE_BOM"};
            ht[47] = new Object[]{"cesu-8", "CESU_8"};
            ht[48] = new Object[]{"x-mswin-936", "MS936", new Object[]{"gbk", "GBK", new Object[]{"x-utf-32be-bom", "UTF_32BE_BOM"}}};
            ht[53] = new Object[]{"x-windows-950", "MS950"};
            ht[54] = new Object[]{"x-windows-874", "MS874"};
            ht[56] = new Object[]{"koi8-r", "KOI8_R"};
            ht[59] = new Object[]{"koi8-u", "KOI8_U"};
            ht[62] = new Object[]{"utf-32le", "UTF_32LE"};
        }
    }
    
    // [规范名-字符集实例]映射（初始时只包含常用实例）
    private static final class Cache extends sun.util.PreHashedMap<Charset> {
        
        private static final int ROWS = 64;
        private static final int SIZE = 54;
        private static final int SHIFT = 0;
        private static final int MASK = 0x3f;
        
        private Cache() {
            super(ROWS, SIZE, SHIFT, MASK);
        }
        
        protected void init(Object[] ht) {
            ht[0] = new Object[]{"ibm862", null};
            ht[2] = new Object[]{"windows-31j", null};
            ht[4] = new Object[]{"ibm866", null, new Object[]{"utf-16le", null}};
            ht[5] = new Object[]{"utf-32", null};
            ht[6] = new Object[]{"windows-1250", null};
            ht[7] = new Object[]{"windows-1251", null};
            ht[8] = new Object[]{"windows-1252", null, new Object[]{"utf-32be", null}};
            ht[9] = new Object[]{"windows-1253", null};
            ht[10] = new Object[]{"windows-1254", null};
            ht[11] = new Object[]{"windows-1255", null, new Object[]{"utf-16", null}};
            ht[12] = new Object[]{"windows-1256", null, new Object[]{"x-ms950-hkscs", null}};
            ht[13] = new Object[]{"windows-1257", null};
            ht[14] = new Object[]{"windows-1258", null, new Object[]{"utf-16be", null}};
            ht[15] = new Object[]{"x-johab", null};
            ht[16] = new Object[]{"jis_x0201", null, new Object[]{"iso-8859-1", null}};
            ht[17] = new Object[]{"iso-8859-2", null};
            ht[18] = new Object[]{"utf-8", null};
            ht[19] = new Object[]{"iso-8859-4", null};
            ht[20] = new Object[]{"iso-8859-5", null};
            ht[22] = new Object[]{"x-ibm874", null, new Object[]{"iso-8859-7", null}};
            ht[23] = new Object[]{"shift_jis", null};
            ht[24] = new Object[]{"iso-8859-9", null};
            ht[25] = new Object[]{"x-ms950-hkscs-xp", null};
            ht[28] = new Object[]{"x-ibm737", null};
            ht[31] = new Object[]{"x-windows-949", null, new Object[]{"ibm850", null}};
            ht[33] = new Object[]{"ibm852", null, new Object[]{"ibm775", null}};
            ht[34] = new Object[]{"us-ascii", null};
            ht[35] = new Object[]{"iso-8859-13", null};
            ht[36] = new Object[]{"ibm855", null, new Object[]{"ibm437", null}};
            ht[37] = new Object[]{"iso-8859-15", null};
            ht[38] = new Object[]{"ibm857", null, new Object[]{"iso-8859-16", null, new Object[]{"x-utf-32le-bom", null}}};
            ht[39] = new Object[]{"ibm00858", null};
            ht[44] = new Object[]{"x-utf-16le-bom", null};
            ht[47] = new Object[]{"cesu-8", null};
            ht[48] = new Object[]{"x-mswin-936", null, new Object[]{"gbk", null, new Object[]{"x-utf-32be-bom", null}}};
            ht[53] = new Object[]{"x-windows-950", null};
            ht[54] = new Object[]{"x-windows-874", null};
            ht[56] = new Object[]{"koi8-r", null};
            ht[59] = new Object[]{"koi8-u", null};
            ht[62] = new Object[]{"utf-32le", null};
        }
        
    }
}