JDBC实现简单的连接池代码

JDBC实现简单的连接池代码

博客分类：

JDBC

JDBCJavaSQLMicrosoft

连接池类：MyDataSource.java

Java代码


package com.itcast.myjdbc.pool;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

import java.util.LinkedList;

public class MyDataSource {

private static final String url="jdbc:sqlserver://localhost:1433;DatabaseName=mytest";

private static final String username="sa";

private static final String password="123456";

//LinkedListy用来添加链接，添加、删除元素比较快。

private LinkedList<Connection> pool = new LinkedList<Connection>();

private int initCount =5;//容器中初始化添加数目

private int maxCount = 10;//容器中最大可以添加的数目

int currentCount = 0;//当前使用的连接数

public MyDataSource() {//初始化添加链接

for(int i=0; i<initCount; i++) {

this.pool.addLast(createConnection());

this.currentCount++;

}

}

public Connection getConnection() throws SQLException {//获取链接

synchronized(pool) {

if(this.pool.size()>0) {

return pool.removeFirst();

}

if(this.currentCount<maxCount) {

return createConnection();

}

throw new SQLException("已没有链接");

}

}

public void free(Connection conn) {//释放链接

pool.addLast(conn);

}

public Connection createConnection() {//创建连接

Connection conns = null;

try {

conns = DriverManager.getConnection(url, username, password);

} catch (SQLException e) {

System.out.println("创建链接失败");

}

return conns;

}

public LinkedList<Connection> getPool() {

return pool;

}

public void setPool(LinkedList<Connection> pool) {

this.pool = pool;

}

}

测试类：Test .java

Java代码


package com.itcast.myjdbc.pool;

import java.sql.Connection;

import java.sql.SQLException;

public class Test {

public static void main(String[] args) throws SQLException {

try {

Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

} catch (ClassNotFoundException e) {

System.out.println("加载驱动失败");

}

MyDataSource myDatasource = new MyDataSource();

for(int i=0; i<30; i++) {//输出三十个连接

Connection conn = myDatasource.getConnection();

System.out.println(conn);

myDatasource.free(conn);

}

}

}