关于全角半角转换（转）

见谅未能注明出处：

    第一种方法:
    /**
     * 特殊字符串转换
     * @Class Name FullCharConverter
     * @Author v-jiangwei
     * @Create In 2012-8-24
     */
    public class FullCharConverter {

    /**
    * 全角转半角的 转换函数
    * @Methods Name full2HalfChange
    * @Create In 2012-8-24 By v-jiangwei
    * @param QJstr
    * @return String
    */
    public static final String full2HalfChange(String QJstr)
    {
    StringBuffer outStrBuf = new StringBuffer("");
    String Tstr = "";
    byte[] b = null;
    for (int i = 0; i < QJstr.length(); i++) {
    Tstr = QJstr.substring(i, i + 1);
    // 全角空格转换成半角空格
    if (Tstr.equals("　")) {
    outStrBuf.append(" ");
    continue;
    }
    try {
    b = Tstr.getBytes("unicode");
    // 得到 unicode 字节数据
    if (b[2] == -1) {
    // 表示全角
    b[3] = (byte) (b[3] + 32);
    b[2] = 0;
    outStrBuf.append(new String(b, "unicode"));
    } else {
    outStrBuf.append(Tstr);
    }
    } catch (UnsupportedEncodingException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    }

    } // end for.
    return outStrBuf.toString();


    }

     

    /**
    * 半角转全角
    * @Methods Name half2Fullchange
    * @Create In 2012-8-24 By v-jiangwei
    * @param QJstr
    * @return String
    */
    public static final String half2Fullchange(String QJstr)
    {
    StringBuffer outStrBuf = new StringBuffer("");
    String Tstr = "";
    byte[] b = null;
    for (int i = 0; i < QJstr.length(); i++) {
    Tstr = QJstr.substring(i, i + 1);
    if (Tstr.equals(" ")) {
    // 半角空格
    outStrBuf.append(Tstr);
    continue;
    }
    try {
    b = Tstr.getBytes("unicode");
    if (b[2] == 0) {
    // 半角
    b[3] = (byte) (b[3] - 32);
    b[2] = -1;
    outStrBuf.append(new String(b, "unicode"));
    } else {
    outStrBuf.append(Tstr);
    }
    return outStrBuf.toString();
    } catch (UnsupportedEncodingException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    }

    }
    return outStrBuf.toString();
    }


    /**
    * @Methods Name main
    * @Create In 2012-8-24 By v-jiangwei
    * @param args
    *            void
    */
    public static void main(String[] args) {
    // TODO Auto-generated method stub
    String QJstr = "８１４乡道";
    String result = FullCharConverter.full2HalfChange(QJstr);
    System.out.println(QJstr);
    System.out.println(result);
    System.out.println("------------------------------------");
    // 半角转全角
    String str = "G45大广高速";
    System.out.println(str);
    System.out.println(FullCharConverter.half2Fullchange(str));
    }


    }
    第二种方法:
    /**
         * 半角转全角
         * @param input String.
         * @return 全角字符串.
         */
    public static String ToSBC(String input) {
             char c[] = input.toCharArray();
             for (int i = 0; i < c.length; i++) {
               if (c[i] == ' ') {
                 c[i] = 'u3000';
               } else if (c[i] < '177') {
                 c[i] = (char) (c[i] + 65248);


               }
             }
             return new String(c);
    }
     
         /**
         * 全角转半角
         * @param input String.
         * @return 半角字符串
         */
     public static String ToDBC(String input) {
         char c[] = input.toCharArray();
              for (int i = 0; i < c.length; i++) {
                if (c[i] == 'u3000') {
                  c[i] = ' ';
                } else if (c[i] > 'uFF00' && c[i] < 'uFF5F') {
                  c[i] = (char) (c[i] - 65248);


                }
              }
              String returnString = new String(c);
              return returnString;
     }
        public static void main(String[] args) {
        String QJstr = "Ｇ４５大广高速";
    String result = StringUtil.ToDBC(QJstr);
    System.out.println(result);

    }

这里面对第一种说明下，对于一个字符，当转换为unicode编码时候，所对应的byte数组，第三个值对应0或者1,0代表半角，1代表全角