JDBC 数据库连接池

作者：网络转载发布时间：[ 2013/8/6 10:21:11 ] 推荐标签：

　　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;

/***
* 数据库连接池实现类
* @author dream
*
*/
public class JDBCPool {
//存放连接的集合
private static LinkedList<Connection> dblist=new LinkedList<Connection>();
//连接池容量
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("数据库连接池无数据库连接！");
}
return dblist.removeFirst();
}
public static int getConnectionNumber(){
return dblist.size();
}

/***
* 数据库连接代理类
* @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;//方法返回值
   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;
}

}
}