1 //实现DataSource接口
2 public class MyConn implements DataSource {
3 //声明池管理对象
4 private LinkedList<Connection> pool =new LinkedList<Connection>();
5 //在构造函数中初始化，创建多个连接
6 public MyConn()
7 {
8 try {
9 Class.forName("com.mysql.jdbc.Driver");
10 String url="jdbc:mysql://localhost:3306/jdbcdb";
11 for(int i=0;i<3;i++)
12 {
13 final Connection conn =DriverManager.getConnection(url,"root","mysql");
14
15 Object ProxyedConn= Proxy.newProxyInstance(
16 MyConn.class.getClassLoader(), //类加载器
17 new Class[]{Connection.class}, //被代理类的父接口
18 new InvocationHandler() { //句柄，获取代理类的方法
19 public Object invoke(Object proxyedConnection, Method method, Object[] args)
20 throws Throwable {
21
22 if(method.getName().equals("close"))
23 {
24 synchronized (pool) {
25 pool.addLast((Connection)proxyedConnection);
26 pool.notify();
27 }
28 return null;
29 }
30 //目标方法的返回值
31 Object returnValue=method.invoke(conn, args);//conn，你要代理的对象
32 return returnValue;
33 }
34 });
35
36 pool.add((Connection)ProxyedConn);
37 }
38 } catch (Exception e) {
39 e.printStackTrace();
40 }
41 }
42
43 public Connection getConnection() throws SQLException {
44
45 synchronized (pool) {
46 if(pool.size()==0)//池中是否还有连接，如果没有等待
47 {
48 try {
49 pool.wait();
50 } catch (InterruptedException e) {
51 e.printStackTrace();
52 }
53 return getConnection();//递归
54 }
55
56 Connection conn= pool.removeFirst();//移除第一个
57 return conn;
58 }
59
60 }
