文字列指定の長さの切り取り

package com.common;

/**
 *         
 * @author S.J
 * @version 1.0, 11/03/2009
 */
public class CharactorLength {
	
	public final static int LENGTH_COMMON = 60;
	public final static int LENGTH_SHORT = 40;
	public final static int LENGTH_ICONS_VIEW = 20;
	
	/**
	 *        Ascill        （  ， ，    ）
	 * @param char c,        
	 * @return boolean,   true,Ascill  
	 */
	public static boolean isLetter(char c) {
	    int k = 0x80;
	    return c / k == 0 ? true : false;
	}
	
	/**
	 *           ,     ,           2,       1
	 * @param String s,           
	 * @return int,         
	 */
	public static int length(String s) {
	    if (s == null)
	        return 0;
	    char[] c = s.toCharArray();
	    int len = 0;
	    for (int i = 0; i < c.length; i++) {
	        len++;
	        System.out.println("compare " + c[i] + " is letter? ");
	        if (!isLetter(c[i])) {
	            len++;
	            System.out.print("No");
	        }
	        System.out.println("");
	    }
	    return len;
	}
	
	/**
	 *          ,      ,       ，        
	 * @author patriotlml
	 * @param String origin,      
	 * @param int len,     (       2  )
	 * @return String,       
	 */
	public static String substring(String originString, int len) {
		System.out.println("substring start----------------");
		String origin = null;
		try{
			origin = originString;//StringConverter.asciiToUnicode(originString);
			System.out.println(origin);
			System.out.println("ISO-8859-1-UTF8 "+new String(originString.getBytes("ISO-8859-1"), "UTF-8"));
			System.out.println("ISO-8859-1-GBK "+new String(originString.getBytes("ISO-8859-1"), "GBK"));
			System.out.println("ISO-8859-1-GB2312 "+new String(originString.getBytes("ISO-8859-1"), "GB2312"));
			System.out.println("ISO-8859-1-UNICODE "+new String(originString.getBytes("ISO-8859-1"), "UNICODE"));
			System.out.println("UNICODE-UTF8 "+new String(originString.getBytes("UNICODE"), "UTF-8"));
			System.out.println("UNICODE-GBK "+new String(originString.getBytes("UNICODE"), "GBK"));
			System.out.println("UNICODE-GB2312 "+new String(originString.getBytes("UNICODE"), "GB2312"));
			System.out.println("UNICODE-ISO-8859-1 "+new String(originString.getBytes("UNICODE"), "ISO-8859-1"));
			System.out.println("UTF8-GBK "+new String(originString.getBytes("UTF-8"), "GBK"));
			System.out.println("UTF8-GB2312 "+new String(originString.getBytes("UTF-8"), "GB2312"));
			System.out.println("UTF8-UNICODE "+new String(originString.getBytes("UTF-8"), "UNICODE"));
			System.out.println("UTF8-ISO-8859-1 "+new String(originString.getBytes("UTF-8"), "ISO-8859-1"));
			System.out.println("GBK-UTF8 "+new String(originString.getBytes("GBK"), "UTF-8"));
			System.out.println("GBK-UNICODE "+new String(originString.getBytes("GBK"), "UNICODE"));
			System.out.println("GBK-ISO-8859-1 "+new String(originString.getBytes("GBK"), "ISO-8859-1"));
			System.out.println("GBK-GB2312 "+new String(originString.getBytes("GBK"), "GB2312"));
			System.out.println("GB2312-UTF8 "+new String(originString.getBytes("GB2312"), "UTF-8"));
			System.out.println("GB2312-UNICODE "+new String(originString.getBytes("GB2312"), "UNICODE"));
			System.out.println("GB2312-ISO-8859-1 "+new String(originString.getBytes("GB2312"), "ISO-8859-1"));
			System.out.println("GB2312-GBK "+new String(originString.getBytes("GB2312"), "GBK"));
		}catch(Exception e){
			e.printStackTrace();
		}
	    if (origin == null || origin.equals("") || len < 1)
	        return "";
	    byte[] sbt = originString.getBytes();
	    System.out.println("sbt start:::::::::::::::::::::::::");
	    for(int i=0; i<sbt.length; i++){
	    	System.out.print(sbt[i]);
	    }
	    System.out.println("
sbt end:::::::::::::::::::::::::");
	    byte[] strByte = new byte[len];
	    if (len >= length(origin)){
	        return origin;
	    }
	    System.out.println("strByte.length=" + strByte.length);
	    strByte = origin.substring(0, len).getBytes();
	//	        System.arraycopy(origin , 0, strByte, 0, len);
	    int count = 0;
	    for (int i = 0; i < len; i++) {
	        int value = (int) strByte[i];
	        System.out.println("strByte_" + i + strByte[i]);
	        if (value < 0) {
	            count++;
	        }
	    }
	    System.out.println("count=" + count);
	    if (count % 2 != 0) {
	        len = (len == 1) ? ++len : --len;
	    }
	    System.out.println("len=" + len);
	    return new String(strByte, 0, len) + "...";
	}

	public static void main(String[] args) {
		String str = "-56-3-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-54-65-51-88-50-64-51-88";
		String str_cn = "                                                        ";
		System.out.println(substring(str, LENGTH_SHORT));
		System.out.println(substring(str_cn, LENGTH_SHORT));
	}

}