用C3P0完成数据库的连接

1.封装的javabean

package com.csdn.hbsi.domain;

public class User {

private int id;

private String name;

private double price;

private String author;

private String description;

public int getId() {

return id;

}

public void setId(int id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public double getPrice() {

return price;

}

public void setPrice(double price) {

this.price = price;

}

public String getAuthor() {

return author;

}

public void setAuthor(String author) {

this.author = author;

}

public String getDescription() {

return description;

}

public void setDescription(String description) {

this.description = description;

}

}

2.package com.csdn.hbsi.demo;

import java.sql.SQLException;

import java.util.List;

import org.apache.commons.dbutils.QueryRunner;

import org.apache.commons.dbutils.ResultSetHandler;

import org.apache.commons.dbutils.handlers.BeanHandler;

import org.apache.commons.dbutils.handlers.BeanListHandler;

import org.junit.Test;

import com.csdn.hbsi.domain.User;

import com.csdn.hbsi.utils.DBManager;

public class demo_crud {

@Test

public void insert() throws SQLException {

QueryRunner runner = new QueryRunner(DBManager.getDataSource());

String sql = "insert into book(id,name,price,author,description) values(?,?,?,?,?)";

Object params[] = { 5, "cc", "66", "cccc", "dd" };

runner.update(sql, params);

}

@Test

public void update() throws SQLException {

QueryRunner runner = new QueryRunner(DBManager.getDataSource());

String sql = "update book set name=? where id=?";

Object params[] = { "eeee", 3 };

runner.update(sql, params);

}

@Test

public void delete() throws SQLException {

QueryRunner runner = new QueryRunner(DBManager.getDataSource());

String sql = "delete from book where id=?";

Object params[] = { 3 };

runner.update(sql, params);

}

@SuppressWarnings("deprecation")

@Test

public void find() throws SQLException {

QueryRunner runner = new QueryRunner(DBManager.getDataSource());

String sql="select * from book where id=?";

User user=(User) runner.query(sql, 1, new BeanHandler(User.class));

System.out.println(user);

}

@Test

public void findall() throws SQLException {

QueryRunner runner = new QueryRunner(DBManager.getDataSource());

String sql="select * from book";

List list=(List) runner.query(sql, new BeanListHandler(User.class));

System.out.println(list.size());

}

}

3.配置文件

com.mysql.jdbc.Driverjdbc:mysql://localhost:3306/testroot123510530com.mysql.jdbc.Driverjdbc:mysql://localhost:3306/testroot123510530

4.package com.csdn.hbsi.utils;

import com.mchange.v2.c3p0.ComboPooledDataSource;

public class DBManager {

private static ComboPooledDataSource ds=null;

static{

ds = new ComboPooledDataSource();

}

public static ComboPooledDataSource getDataSource(){

return ds;

}

}