JDBC ??????????

???????????? ???????[ 2013/8/6 10:21:11 ] ????????

????Code

package xgn.jdbc;

import java.io.InputStream;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.sql.Connection;
import java.sql.DriverManager;
import java.util.LinkedList;
import java.util.Properties;

/***
* ???????????????
* @author dream
*
*/
public class JDBCPool {
//???????????
private static LinkedList<Connection> dblist=new LinkedList<Connection>();
//?????????
private static final int number=100;
static{
try{
   Properties config=new Properties();
   InputStream in= JDBCPool.class.getClassLoader().getResourceAsStream("config.properties");
   config.load(in);
   for(int i=0;i<number;i++){
    Connection cn= DriverManager.getConnection(config.getProperty("Connstr")??config.getProperty("user")??config.getProperty("pwd"));
    ConnectionProxy conn=new ConnectionProxy(cn);
    Connection proxycn=conn.getConnectionProxy(cn??new Class[]{Connection.class}??conn);
    dblist.addFirst(proxycn);
   }
}catch(Exception ex){
   throw new RuntimeException(ex);
}
}
public static void recoverConnection(Connection cn){
dblist.addFirst(cn);
}
public static Connection getConnection(){
if(dblist.size()<=0){
   throw new RuntimeException("??????????????????????");
}
return dblist.removeFirst();
}
public static int getConnectionNumber(){
return dblist.size();
}

/***
* ??????????????
* @author dream
*
*/
public static class ConnectionProxy implements InvocationHandler {
private Object obj=null;
private Object proxyobj=null;
@Override
public Object invoke(Object arg0?? Method arg1?? Object[] arg2)throws Throwable {
   Object ret=null;//?????????
   if(arg1.getName()=="close"){
    System.out.println("close");
    JDBCPool.recoverConnection((Connection)this.proxyobj);
    return ret;
   }
   ret=arg1.invoke(this.obj?? arg2);
   return ret;
}
public ConnectionProxy(Connection cn){
   this.obj=cn;
}

public Connection getConnectionProxy(Connection cn??Class[] cls??InvocationHandler h){
   this.proxyobj= Proxy.newProxyInstance(cn.getClass().getClassLoader()??cls??h);
   return (Connection)this.proxyobj;
}

}
}