/*

 * 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

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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;

public class StandardCharsets extends CharsetProvider {

    _INCLUDE_ALIASES_TABLES_

    _INCLUDE_ALIASES_MAP_

    _INCLUDE_CLASSES_MAP_

    _INCLUDE_CACHE_MAP_

    // Maps canonical names to class names

    private @Stable Map<String,String> classMap;

    // Maps alias names to canonical names

    private @Stable Map<String,String> aliasMap;

    // Maps canonical names to cached instances

    private @Stable Map<String,Charset> cache;

    private static final String packagePrefix = "sun.nio.cs.";

    public StandardCharsets() {

    }

    private String canonicalize(String csn) {

        String acn = aliasMap().get(csn);

        return (acn != null) ? acn : csn;

    }

    private Map<String,String> aliasMap() {

        Map<String,String> map = aliasMap;

        if (map == null) {

            aliasMap = map = new Aliases();

        }

        return map;

    }

    private Map<String,String> classMap() {

        Map<String,String> map = classMap;

        if (map == null) {

            classMap = map = new Classes();

        }

        return map;

    }

    private Map<String,Charset> cache() {

        Map<String,Charset> map = cache;

        if (map == null) {

            map = new Cache();

            cache = map;

        }

        return map;

    }

    // Private ASCII-only version, optimized for interpretation during startup

    //

    private static String toLower(String s) {

        int n = s.length();

        boolean allLower = true;

        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();

    }

    private Charset lookup(String charsetName) {

        init();

        // By checking these built-ins we can avoid initializing Aliases and

        // Classes eagerly during bootstrap

        String csn;

        if (charsetName.equals("UTF-8")) {

        } else if (charsetName.equals("US-ASCII")) {

        } else if (charsetName.equals("ISO-8859-1")) {

        } else {

            csn = canonicalize(toLower(charsetName));

        }

        // Check cache first

        Charset cs = cache().get(csn);

        if (cs != null)

            return cs;

        // Do we even support this charset?

        String cln = classMap().get(csn);

        if (cln == null)

            return null;

        // Instantiate the charset and cache it

        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;

        }

    }

    private Charset cache(String csn, Charset cs) {

        cache().put(csn, cs);

        return cs;

    }

    public final Charset charsetForName(String charsetName) {

        synchronized (this) {

            return lookup(charsetName);

        }

    }

    public final Iterator<Charset> charsets() {

        Set<String> charsetNames;

        synchronized (this) {

            init();

            // Ensure initialized in synchronized block

            charsetNames = classMap().keySet();

            aliasMap();

            cache();

        }

        return new Iterator<Charset>() {

                Iterator<String> i = charsetNames.iterator();

                public boolean hasNext() {

                    return i.hasNext();

                }

                public Charset next() {

                    String csn = i.next();

                    return lookup(csn);

                }

                public void remove() {

                    throw new UnsupportedOperationException();

                }

            };

    }

    private boolean initialized = false;

    /*   provider the sun.nio.cs.map property fir sjis/ms932 mapping hack

     */

    private void init() {

        if (initialized)

            return;

        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 (int i = 0; i < maps.length; i++) {

                if (maps[i].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;

                }

            }

        }

    }

}