gbk资料转utf-8 Demo

gbk文件转utf-8 Demo
读取gbk编码的文件,并将其转为utf-8编码后输出:

import java.io.File;
import java.io.RandomAccessFile;
import java.io.UnsupportedEncodingException;


public class Test1 {
public static String readTxt(int off,int leng) {
  RandomAccessFile r;
  String str = "";
  try {
   r = new RandomAccessFile(new File("D:/test.txt"), "r");
   byte[] c = new byte[leng];
   r.seek(off);
   r.read(c);
   str = new String(c);
  } catch (Exception e) {
   e.printStackTrace();
  }
  return str;
}
   
  public static byte[] gbk2utf8(String chenese){   
   char c[] = chenese.toCharArray();   
         byte [] fullByte =new byte[3*c.length];   
         for(int i=0; i<c.length; i++){   
          int m = (int)c[i];   
          String word = Integer.toBinaryString(m);                 
          StringBuffer sb = new StringBuffer();   
          int len = 16 - word.length();  
          for(int j=0; j<len; j++){   
           sb.append("0");   
          }   
          sb.append(word);   
          sb.insert(0, "1110");   
          sb.insert(8, "10");   
          sb.insert(16, "10");   
          String s1 = sb.substring(0,8);             
          String s2 = sb.substring(8,16);             
          String s3 = sb.substring(16);   
             
          byte b0 = Integer.valueOf(s1, 2).byteValue();   
          byte b1 = Integer.valueOf(s2, 2).byteValue();   
          byte b2 = Integer.valueOf(s3, 2).byteValue();   
          byte[] bf = new byte[3];   
          bf[0] = b0;   
          fullByte[i*3] = bf[0];   
          bf[1] = b1;   
          fullByte[i*3+1] = bf[1];   
          bf[2] = b2;   
          fullByte[i*3+2] = bf[2];   
             
         }   
         return fullByte;   
  }  

public static void main(String[] args) {
  String str = readTxt(0,731);
 
  byte [] fullByte = gbk2utf8(str);  
  String fullStr = "";
        try {
   fullStr = new String(fullByte, "UTF-8");
  } catch (UnsupportedEncodingException e) {
   e.printStackTrace();
  }  
  System.out.println(fullStr);
}
}

测试文档D:\test.txt内容:
[账号],[日期],[收支种类],[币种],[收入],[支出],[余额],[摘要]

3819660311,2004-2006-01-05,支出,人民币,0,54.20, 6403.89,消费款


中文可以，正确转换
英文乱码