/*
 * Copyright (c) 2000, 2015, 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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 * questions.
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 */

// -- This file was mechanically generated: Do not edit! -- //

package sun.nio.cs.ext;

import java.lang.ref.SoftReference;
import java.nio.charset.Charset;
import java.nio.charset.spi.CharsetProvider;
import java.security.AccessController;
import java.security.PrivilegedAction;

/**
 * Provider for extended charsets.
 */

public class ExtendedCharsets extends AbstractCharsetProvider {

    static volatile ExtendedCharsets instance = null;

    public ExtendedCharsets() {

        super("sun.nio.cs.ext");  // identify provider pkg name.

        _CHARSETS_DEF_LIST_

        instance = this;

    }

    private boolean initialized = false;

    // If the sun.nio.cs.map property is defined on the command line we won't
    // see it in the system-properties table until after the charset subsystem
    // has been initialized.  We therefore delay the effect of this property
    // until after the JRE has completely booted.
    //
    // At the moment following values for this property are supported, property
    // value string is case insensitive.
    //
    // (1)"Windows-31J/Shift_JIS"
    // In 1.4.1 we added a correct implementation of the Shift_JIS charset
    // but in previous releases this charset name had been treated as an alias
    // for Windows-31J, aka MS932. Users who have existing code that depends
    // upon this alias can restore the previous behavior by defining this
    // property to have this value.
    //
    // (2)"x-windows-50221/ISO-2022-JP"
    //    "x-windows-50220/ISO-2022-JP"
    //    "x-windows-iso2022jp/ISO-2022-JP"
    // The charset ISO-2022-JP is a "standard based" implementation by default,
    // which supports ASCII, JIS_X_0201 and JIS_X_0208 mappings based encoding
    // and decoding only.
    // There are three Microsoft iso-2022-jp variants, namely x-windows-50220,
    // x-windows-50221 and x-windows-iso2022jp which behaves "slightly" differently
    // compared to the "standard based" implementation. See ISO2022_JP.java for
    // detailed description. Users who prefer the behavior of MS iso-2022-jp
    // variants should use these names explicitly instead of using "ISO-2022-JP"
    // and its aliases. However for those who need the ISO-2022-JP charset behaves
    // exactly the same as MS variants do, above properties can be defined to
    // switch.
    //
    // If we need to define other charset-alias mappings in the future then
    // this property could be further extended, the general idea being that its
    // value should be of the form
    //
    //     new-charset-1/old-charset-1,new-charset-2/old-charset-2,...
    //
    // where each charset named to the left of a slash is intended to replace
    // (most) uses of the charset named to the right of the slash.
    //
    protected void init() {
        if (initialized)
            return;
        if (!sun.misc.VM.isBooted())
            return;

        String map = getProperty("sun.nio.cs.map");
        boolean sjisIsMS932 = false;
        boolean iso2022jpIsMS50221 = false;
        boolean iso2022jpIsMS50220 = false;
        boolean iso2022jpIsMSISO2022JP = false;
        if (map != null) {
            String[] maps = map.split(",");
            for (int i = 0; i < maps.length; i++) {
                if (maps[i].equalsIgnoreCase("Windows-31J/Shift_JIS")) {
                    sjisIsMS932 = true;
                } else if (maps[i].equalsIgnoreCase("x-windows-50221/ISO-2022-JP")) {
                    iso2022jpIsMS50221 = true;
                } else if (maps[i].equalsIgnoreCase("x-windows-50220/ISO-2022-JP")) {
                    iso2022jpIsMS50220 = true;
                } else if (maps[i].equalsIgnoreCase("x-windows-iso2022jp/ISO-2022-JP")) {
                    iso2022jpIsMSISO2022JP = true;
                }
            }
        }
        if (sjisIsMS932 && hasCharset("Shift_JIS")) {
            deleteCharset("Shift_JIS",
                          new String[] {
                              // IANA aliases
                              "sjis", // historical
                              "shift_jis",
                              "shift-jis",
                              "ms_kanji",
                              "x-sjis",
                              "csShiftJIS"
                          });
            deleteCharset("windows-31j",
                          new String[] {
                              "MS932", // JDK historical
                              "windows-932",
                              "csWindows31J"
                          });
            charset("Shift_JIS", "SJIS",
                    new String[] {
                        // IANA aliases
                        "sjis"          // JDK historical
                    });
            charset("windows-31j", "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"
                    });
        }
        if (iso2022jpIsMS50221 ||
            iso2022jpIsMS50220 ||
            iso2022jpIsMSISO2022JP) {
            deleteCharset("ISO-2022-JP",
                          new String[] {
                              "iso2022jp",
                                "jis",
                                "csISO2022JP",
                                "jis_encoding",
                                "csjisencoding"
                          });
            if (iso2022jpIsMS50221) {
                deleteCharset("x-windows-50221",
                              new String[] {
                                  "cp50221",
                                  "ms50221"
                              });
                charset("x-windows-50221", "MS50221",
                        new String[] {
                            "cp50221",
                            "ms50221",
                            "iso-2022-jp",
                            "iso2022jp",
                            "jis",
                            "csISO2022JP",
                            "jis_encoding",
                            "csjisencoding"
                        });
            } else if (iso2022jpIsMS50220) {
                deleteCharset("x-windows-50220",
                              new String[] {
                                  "cp50220",
                                  "ms50220"
                              });
                charset("x-windows-50220", "MS50220",
                        new String[] {
                            "cp50220",
                            "ms50220",
                            "iso-2022-jp",
                            "iso2022jp",
                            "jis",
                            "csISO2022JP",
                            "jis_encoding",
                            "csjisencoding"
                        });
            } else {
                deleteCharset("x-windows-iso2022jp",
                              new String[] {
                                  "windows-iso2022jp"
                              });
                charset("x-windows-iso2022jp", "MSISO2022JP",
                        new String[] {
                            "windows-iso2022jp",
                            "iso-2022-jp",
                            "iso2022jp",
                            "jis",
                            "csISO2022JP",
                            "jis_encoding",
                            "csjisencoding"
                        });


            }
        }
        initialized = true;
    }

    private static String getProperty(String key) {
        // this method may be called during initialization of
        // system class loader and thus not using lambda
        return AccessController.doPrivileged(
            new PrivilegedAction<String>() {
                @Override
                public String run() {
                    return System.getProperty(key);
                }
            });
    }

    public static String[] aliasesFor(String charsetName) {
        if (instance == null)
            return null;
        return instance.aliases(charsetName);
    }

}