编码转换

package com.chinabase.common.util;

import java.io.UnsupportedEncodingException;



/**
 * 转换字符串的编码
 * @author yuanji
 * @created on:Sep 19, 2008
 */
public class ChangeCharset {

    
    /** *//** 将字符编码转换成US-ASCII码     */
    public String toASCII(String str) throws UnsupportedEncodingException {
        return this.changeCharset(str, CharContents.US_ASCII);
    }
    
    /** *//** 将字符编码转换成ISO-8859-1     */
    public String toISO_8859_1(String str) throws UnsupportedEncodingException {
        return this.changeCharset(str, CharContents.ISO_8859_1);
    }
    
    /** *//** 将字符编码转换成UTF-8     */
    public String toUTF_8(String str) throws UnsupportedEncodingException {
        return this.changeCharset(str, CharContents.UTF_8);
    }
    
    /** *//** 将字符编码转换成UTF-16BE     */
    public String toUTF_16BE(String str) throws UnsupportedEncodingException{
        return this.changeCharset(str, CharContents.UTF_16BE);
    }
    
    /** *//** 将字符编码转换成UTF-16LE     */
    public String toUTF_16LE(String str) throws UnsupportedEncodingException {
        return this.changeCharset(str, CharContents.UTF_16LE);
    }
    
    /** *//** 将字符编码转换成UTF-16     */
    public String toUTF_16(String str) throws UnsupportedEncodingException {
        return this.changeCharset(str, CharContents.UTF_16);
    }
    
    /** *//** 将字符编码转换成GBK     */
    public String toGBK(String str) throws UnsupportedEncodingException {
        return this.changeCharset(str, CharContents.GBK);
    }
    
    /** *//** 将字符编码转换成GB2312     */
    public String toGB2312(String str) throws UnsupportedEncodingException {
        return this.changeCharset(str,CharContents.GB2312);
    }
    
    /** *//**
     * 字符串编码转换的实现方法
     * @param str    待转换的字符串
     * @param newCharset    目标编码
     */
    public String changeCharset(String str, String newCharset) throws UnsupportedEncodingException {
        if(str != null) {
            //用默认字符编码解码字符串。与系统相关，中文windows默认为GB2312
            byte[] bs = str.getBytes();
            return new String(bs, newCharset);    //用新的字符编码生成字符串
        }
        return null;
    }
    
    /** *//**
     * 字符串编码转换的实现方法
     * @param str    待转换的字符串
     * @param oldCharset    源字符集
     * @param newCharset    目标字符集
     */
    public String changeCharset(String str, String oldCharset, String newCharset) throws UnsupportedEncodingException {
        if(str != null) {
            //用源字符编码解码字符串
            byte[] bs = str.getBytes(oldCharset);
            return new String(bs, newCharset);
        }
        return null;
    }
    
    public static void main(String[] args) throws UnsupportedEncodingException {
        ChangeCharset test = new ChangeCharset();
        String str = "This is a 中文的 String!";
        System.out.println("str：" + str);
        
        String gbk = test.toGBK(str);
        System.out.println("转换成GBK码：" + gbk);
        System.out.println();
        
        String ascii = test.toASCII(str);
        System.out.println("转换成US-ASCII：" + ascii);
        System.out.println();
        
        String iso88591 = test.toISO_8859_1(str);
        System.out.println("转换成ISO-8859-1码：" + iso88591);
        System.out.println();
        
        gbk = test.changeCharset(iso88591, CharContents.ISO_8859_1, CharContents.GBK);
        System.out.println("再把ISO-8859-1码的字符串转换成GBK码：" + gbk);
        System.out.println();
        
        String utf8 = test.toUTF_8(str);
        System.out.println();
        System.out.println("转换成UTF-8码：" + utf8);
        String utf16be = test.toUTF_16BE(str);
        System.out.println("转换成UTF-16BE码：" + utf16be);
        gbk = test.changeCharset(utf16be, CharContents.UTF_16BE, CharContents.GBK);
        System.out.println("再把UTF-16BE编码的字符转换成GBK码：" + gbk);
        System.out.println();
        
        String utf16le = test.toUTF_16LE(str);
        System.out.println("转换成UTF-16LE码：" + utf16le);
        gbk = test.changeCharset(utf16le, CharContents.UTF_16LE, CharContents.GBK);
        System.out.println("再把UTF-16LE编码的字符串转换成GBK码：" + gbk);
        System.out.println();
        
        String utf16 = test.toUTF_16(str);
        System.out.println("转换成UTF-16码：" + utf16);
        String gb2312 = test.changeCharset(utf16, CharContents.UTF_16, CharContents.GB2312);
        System.out.println("再把UTF-16编码的字符串转换成GB2312码：" + gb2312);
    }

}