Example code summary of three methods to implement java character transcoding

//用于解码的构造器: 
String(byte[] bytes, int offset, int length, String charsetName)  
String(byte[] bytes, String charsetName)  
 
用于编码的方法: 
byte[] getBytes(String charsetName) //使用指定字符集进行编码 
 byte[] getBytes() //使用系统默认字符集进行编码

public void convertionString() throws UnsupportedEncodingException{ 
    String s = "清山"; 
    byte[] b = s.getBytes("gbk");//编码 
    String sa = new String(b, "gbk");//解码:用什么字符集编码就用什么字符集解码 
    System.out.println(sa); 
     
    b = sa.getBytes("utf-8");//编码 
    sa = new String(b, "utf-8");//解码 
    System.err.println(sa); 
  }

package com.qingshan.io; 
 
import java.io.FileInputStream; 
import java.io.FileOutputStream; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.InputStreamReader; 
import java.io.OutputStream; 
import java.io.OutputStreamWriter; 
import java.io.UnsupportedEncodingException; 
 
/** 
 * <pre class="brush:php;toolbar:false"> 
 * 使用java.io桥转换:对文件进行转码 
 * 

*

---

* 2012 Qingshan Group 版权所有 *

---

* @author thetopofqingshan * @version 1.0.0 * @since JDK 1.5 * @date 2012-4-28 */ public class CharsetConvertion { private FileInputStream fis;// 文件输入流:读取文件中内容 private InputStream is; private InputStreamReader isr; private OutputStream os; private OutputStreamWriter osw;//写入 private char[] ch = new char[1024]; public void convertionFile() throws IOException{ is = new FileInputStream("C:/项目进度跟踪.txt");//文件读取 isr = new InputStreamReader(is, "gbk");//解码 os = new FileOutputStream("C:/项目进度跟踪_utf-8.txt");//文件输出 osw = new OutputStreamWriter(os, "utf-8");//开始编码 char[] c = new char[1024];//缓冲 int length = 0; while(true){ length = isr.read(c); if(length == -1){ break; } System.out.println(new String(c, 0, length)); osw.write(c, 0, length); osw.flush(); } } public void convertionString() throws UnsupportedEncodingException{ String s = "清山集团"; byte[] b = s.getBytes("gbk");//编码 String sa = new String(b, "gbk");//解码:用什么字符集编码就用什么字符集解码 System.out.println(sa); b = sa.getBytes("utf-8");//编码 sa = new String(b, "utf-8");//解码 System.err.println(sa); } /** *

 
   * 关闭所有流 
   * 

* */ public void close(){ if(isr != null){ try { isr.close(); } catch (IOException e) { e.printStackTrace(); } } if(is != null){ try { is.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } if(osw != null){ try { osw.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } if(os != null){ try { os.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } /** *

 
   * 用io读取文件内容 
   * 

* * @throws IOException * 读取过程中发生错误 * */ /** *

 
   * 
   * 

* @param path * @param charset * @throws IOException * */ public void read(String path, String charset) throws IOException { fis = new FileInputStream(path); isr = new InputStreamReader(fis, charset); while (fis.available() > 0) { int length = isr.read(ch); System.out.println(new String(ch)); } } public static void main(String[] args) { try { CharsetConvertion cc = new CharsetConvertion(); cc.convertionFile(); cc.convertionString(); cc.close(); } catch (IOException e) { e.printStackTrace(); } } }

package com.qingshan.nio; 
 
import java.io.FileInputStream; 
import java.io.FileOutputStream; 
import java.io.IOException; 
import java.io.InputStreamReader; 
import java.nio.ByteBuffer; 
import java.nio.CharBuffer; 
import java.nio.channels.FileChannel; 
import java.nio.charset.Charset; 
import java.nio.charset.CharsetDecoder; 
import java.nio.charset.CharsetEncoder; 
 
/** 
 * <pre class="brush:php;toolbar:false"> 
 * 使用nio中的Charset转换字符:整个流程是文件读取-->byte-->解码(正确)-->编码--->byte-->写入文件 
 * 

*

---

* * 2012 Qingshan Group 版权所有 *

---

* * * @author thetopofqingshan * @version 1.0.0 * @since JDK 1.5 * @date 2012-4-27 */ public class CharsetConvertion { private FileInputStream fis;// 文件输入流:读取文件中内容 private FileChannel in;// 文件通道:双向,流从中而过 private FileChannel out;// 文件通道:双向,流从中而过 private FileOutputStream fos;// 文件输出流:向文件中写入内容 private ByteBuffer b = ByteBuffer.allocate(1024 * 3);// 设置缓存区的大小 private Charset inSet;// 解码字符集 private Charset outSet;// 编码字符集 private CharsetDecoder de;// 解码器 private CharsetEncoder en;// 编码器 private CharBuffer convertion;// 中间的字符数据 private ByteBuffer temp = ByteBuffer.allocate(1024 * 3);// 设置缓存区的大小:临时 private byte[] by = new byte[1024]; private InputStreamReader isr; private char[] ch = new char[1024]; /** *

 
   * 
   * 

* * @param src * @param dest * @throws IOException * */ public void convertionFile_nio(String src, String dest) throws IOException { fis = new FileInputStream(src); in = fis.getChannel(); fos = new FileOutputStream(dest); out = fos.getChannel(); inSet = Charset.forName("gbk"); outSet = Charset.forName("utf-8"); de = inSet.newDecoder(); en = outSet.newEncoder(); while (fis.available() > 0) { b.clear();// 清除标记 in.read(b); // 将文件内容读入到缓冲区内:将标记位置从0-b.capacity(), // 读取完毕标记在0-b.capacity()之间 b.flip();// 调节标记,下次读取从该位置读起 convertion = de.decode(b);// 开始编码 temp.clear();// 清除标记 temp = en.encode(convertion); b.flip(); // 将标记移到缓冲区的开始,并保存其中所有的数据:将标记移到开始0 out.write(temp); // 将缓冲区内的内容写入文件中:从标记处开始取出数据 } } /** *

 
   * 测试转码是否成功, 指定字符集读取文件 
   * 

* * @param src * 被复制文件全路径 * @param charset 解码字符集 * * @throws IOException 读取过程中的发生的异常 * */ public void read(String path, String charset) throws IOException { fis = new FileInputStream(path); isr = new InputStreamReader(fis, charset); while (fis.available() > 0) { int length = isr.read(ch); System.out.println(new String(ch)); } } /** *

 
   * 关闭所有流或通道 
   * 

* */ public void close() { try { if (in != null) { in.close(); } } catch (IOException e) { e.printStackTrace(); } try { if (out != null) { out.close(); } } catch (IOException e) { e.printStackTrace(); } try { if (fis != null) { fis.close(); } } catch (IOException e) { e.printStackTrace(); } try { if (fos != null) { fos.close(); } } catch (IOException e) { e.printStackTrace(); } } public static void main(String[] args) { CharsetConvertion n = new CharsetConvertion(); try { n.convertionFile_nio("C:/项目进度跟踪.txt", "C:/nio_write.txt"); // n.read("C:/nio_write.txt", "utf-8");// 正确 // n.read("C:/nio_write.txt", "gbk");//乱码 } catch (IOException e) { e.printStackTrace(); } finally { n.close(); } } }