import java.io.UnsupportedEncodingException; 
import java.nio.charset.Charset; 
public class TestCharset { 
  public static void main(String[] args) throws UnsupportedEncodingException {  
    String strChineseString = "中文"; 
    String encoding = System.getProperty("file.encoding"); 
    System.out.println("系统默认的字符集是:" + encoding); 
    System.out.println(strChineseString.getBytes(Charset.forName("GBK")).length); 
    System.out.println(strChineseString.getBytes(Charset.forName("UTF-8")).length); 
    System.out.println(strChineseString.getBytes().length); 
  } 
} 

import java.io.UnsupportedEncodingException; 
import java.nio.charset.Charset; 
public class TestCharset { 
  public static void main(String[] args) throws UnsupportedEncodingException { 
    String strChineseString = "中文"; 
    byte[] byteGBK = null; 
    byte[] byteUTF8 = null; 
    byteGBK = strChineseString.getBytes(Charset.forName("GBK")); 
    byteUTF8 = strChineseString.getBytes(Charset.forName("utf-8")); 
    System.out.println(new String(byteGBK,"GBK")); 
    System.out.println(new String(byteGBK,"utf-8")); 
    System.out.println("**************************"); 
    System.out.println(new String(byteUTF8,"utf-8")); 
    System.out.println(new String(byteUTF8,"GBK")); 
  } 
} 

String strSource = "你想要转码的字符串"; 
String strSomeEncoding = "utf-8";  //例如utf-8 
String strTarget = new String (strSource.getBytes(Charset.forName(strSomeEncoding)), strSomeEncoding);  

import java.io.BufferedReader; 
import java.io.DataOutputStream; 
import java.io.IOException; 
import java.io.OutputStreamWriter; 
import java.io.PrintWriter; 
import java.net.Socket; 
public class TestSocket { 
  public static void main(String[] args) throws IOException { 
    Socket socket = new Socket(); 
    DataOutputStream dos = null; 
    PrintWriter pw = null;    
    BufferedReader in = null; 
    String responseXml = "要传输的中文"; 
    //.......... 
    dos = new DataOutputStream(socket.getOutputStream()); 
    pw = new PrintWriter(new OutputStreamWriter(dos)); //不带自动刷新的Writer      
    pw.println(responseXml); 
    pw.flush(); 
  } 
} 

<%@ page contentType="text/html; charset=utf-8" language="java" errorPage="" %>  

<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />  

var url ="http://www.baidu.com/s?industry=编码" 
url = encodeURI(url);  

<%@ page import="java.net.URLEncoder" %>

<a href="xxxxx.xx?industry=<%=URLEncoder.encode(" rel="external nofollow" http://www.baidu.com/s?wd=编码", "UTF-8")%>">  

request.setCharacterEncoding("utf-8"); 
String industry = new String( 
request.getParameter("industry ").getBytes("ISO8859-1"),"UTF-8");  

xmlHttp.open("post", url , true); 
xmlHttp.setRequestHeader("Content-Type","text/xml; charset= utf-8");  
xmlHttp.send(param);  

/** 
 * @Function:writeResponse 
 * @Description:ajax方式返回字符串 
 * @param str:json 
 * @return:true:输出成功，false:输出失败 
 */ 
public boolean writeResponse(String str){ 
  boolean ret = true; 
  try{ 
    HttpServletResponse response = ServletActionContext.getResponse(); 
    response.setContentType("text/html;charset=utf-8"); 
    PrintWriter pw = response.getWriter(); 
    pw.print(str); 
    pw.close(); 
  }catch (Exception e) { 
    ret = false; 
    e.printStackTrace(); 
  } 
  return ret; 
}   

HttpServletResponse response = ServletActionContext.getResponse(); 
response.setContentType("text/html;charset=utf-8"); 
response.reset(); 
String header = "attachment; filename=" + picName; 
   header = new String(header.getBytes(), "UTF-8"); 
   response.setHeader("Content-disposition", header);