ThreadLocal的用法（小程序）

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

/**
 * 采用ThreadLocal封装Connection
 * @author Administrator
 *
 */
public class ConnectionManager {

 private static ThreadLocal<Connection> connectionHolder = new ThreadLocal<Connection>(); 
 
 public static Connection getConnection(){
  Connection conn = connectionHolder.get();
  //如果当前线程中没有绑定相应的Connection
  if(conn == null){
   try {
    JdbcConfig jdbcConfig = XmlConfigReader.getInstance().getJdbcConfig();  
    Class.forName(jdbcConfig.getDirverName());
    conn = DriverManager.getConnection(jdbcConfig.getUrl(), jdbcConfig.getUserName(), jdbcConfig.getPassword());
    //将Connection设置到线程变量中
    connectionHolder.set(conn);
   } catch (ClassNotFoundException e) {
    e.printStackTrace();
    throw new ApplicationException("系统错误，请联系系统管理员!");
   } catch (SQLException e) {
    e.printStackTrace();
    throw new ApplicationException("系统错误，请联系系统管理员!");
   }
  }

  return conn;
 }
 
 public static void closeConnection(){
  Connection conn = connectionHolder.get();
  if(conn != null){
   try {
    conn.close();
    //从ThreadLocal 中清除Connection
    connectionHolder.remove();
   } catch (SQLException e) {    
    e.printStackTrace();
   }
  }
 }
 
}