charsets.java

一个简单的java邮件系统

/*
 * @(#)Charsets.java
 *
 * Copyright (C) 2005 Sergey Bredikhin
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 * This program 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 for more details.
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
 * USA.
 */

package olivax.webmail;

import java.util.Comparator;
import java.util.Hashtable;

public class Charsets {
	public static final String Global[][] = { { "UTF-8", "utf-8" },
			{ "UTF-16", "utf-16" }, { "US-ASCII", "us-ascii" } };

	public static final String WestEuropean[][] = {
			{ "Western (Windows-1252)", "windows-1252" },
			{ "Western (ISO-8859-1)", "iso-8859-1" },
			{ "Western (ISO-8859-15)", "iso-8859-15" },
			{ "Greek (ISO-8859-7)", "iso-8859-7" },
			{ "Greek (Windows-1253)", "windows-1253" },
			{ "South European (ISO-8859-3)", "iso-8859-3" } };

	public static final String EastEuropean[][] = {
			{ "Baltic (ISO-8859-4)", "iso-8859-4" },
			{ "Baltic (ISO-8859-13)", "iso-8859-13" },
			{ "Baltic (Windows-1257)", "windows-1257" },
			{ "Central European (ISO-8859-2)", "iso-8859-2" },
			{ "Cyrillic (ISO-8859-5)", "iso-8859-5" },
			{ "Cyrillic (KOI8-R)", "koi8-r" },
			{ "Cyrillic (Windows-1251)", "windows-1251" } };

	public static final String EastAsian[][] = {
			{ "Chinese (EUC-CN)", "EUC-CN" },
			{ "Chinese Simplified (GBK)", "GBK" },
			{ "Chinese Simplified (GB18030)", "GB18030" },
			{ "Chinese Traditional (Big5)", "Big5" },
			{ "Chinese Traditional (Big5-HKSCS)", "Big5-HKSCS" },
			{ "Taiwanese (EUC-TW)", "EUC-TW" },
			{ "Japanese (EUC-JP)", "EUC-JP" },
			{ "Japanese (Shift_JIS)", "Shift_JIS" },
			{ "Japanese (ISO-2022-JP)", "ISO-2022-JP" },
			{ "Windows (31J)", "31J" }, { "Korean (EUC-KR)", "EUC-KR" },
			{ "Korean (JOHAB)", "JOHAB" },
			{ "Korean (ISO-2022-KR)", "ISO-2022-KR" } };

	public static final String SeAndSwAsian[][] = {
			{ "Thai (TIS-620)", "TIS-620" },
			{ "Turkish (ISO-8859-9)", "ISO-8859-9" },
			{ "Turkish (Windows-1254)", "windows-1254" },
			{ "Vietnamese (Windows-1258)", "windows-1258" } };

	private static void populateFromArray(Hashtable ht, 
			String[][] array, boolean reverse) {
		for (int i = 0; i < array.length; i++) {
			if(reverse) {
				ht.put(array[i][1], array[i][0]);
			} else {
				ht.put(array[i][0], array[i][1]);
			}
		}
	}

	private static Hashtable getHashtable(boolean reverse) {
		Hashtable result = new Hashtable(Global.length + WestEuropean.length
				+ EastEuropean.length + EastAsian.length + SeAndSwAsian.length);
		populateFromArray(result, Global, reverse);
		populateFromArray(result, WestEuropean, reverse);
		populateFromArray(result, EastEuropean, reverse);
		populateFromArray(result, EastAsian, reverse);
		populateFromArray(result, SeAndSwAsian, reverse);
		return result;
	}

	private static final Hashtable htCharsets = getHashtable(false);
	private static final Hashtable htRevCharsets = getHashtable(true);
	
	public static String getCpForName(String name) {
		return (String)htCharsets.get(name);	
	}
	
	public static String getNameForCp(String cp) {
		String name = (String)htRevCharsets.get(cp);
		if(name == null)
			name = cp;
		return name;
	}
	
	public static String[] getCpArray() {
		String cps[] = new String[Global.length + WestEuropean.length
				+ EastEuropean.length + EastAsian.length + SeAndSwAsian.length];
		System.arraycopy(getCpArray(Global), 0, cps, 0, Global.length);
		System.arraycopy(getCpArray(WestEuropean), 0, cps, Global.length,
				WestEuropean.length);
		System.arraycopy(getCpArray(EastEuropean), 0, cps, Global.length
				+ WestEuropean.length, EastEuropean.length);
		System.arraycopy(getCpArray(EastAsian), 0, cps, Global.length
				+ WestEuropean.length + EastEuropean.length, EastAsian.length);
		System.arraycopy(getCpArray(SeAndSwAsian), 0, cps, Global.length
				+ WestEuropean.length + EastEuropean.length + EastAsian.length,
				SeAndSwAsian.length);
		return cps;
	}
	
	private static String[] getCpArray(String[][] cps) {
		String[] res = new String[cps.length]; 
		for(int i = 0; i < cps.length; i++) {
			res[i] = cps[i][1];
		}
		return res;
	}
	
	public static String[] getCpArraySorted() {
		String[] result = getCpArray();
		java.util.Arrays.sort(result, new Comparator() {
			public int compare(Object a, Object b) {
				String o1 = (String) a;
				String o2 = (String) b;
				return o1.compareToIgnoreCase(o2);
			}
		});
		return result;
	}
	
}