快速配置优化数据库连接的c3p0

1.导入两个jar包 :c3p0及mchange包

2. 在src路径下创建c3p0-config.xml,注意名字固定，不能自己随意取,不然识别不了

  
    
    
    com.mysql.jdbc.Driver
    jdbc:mysql://localhost:3306/springmvc
    root
    root
    
    10
    10
    5
    100
    30
    18000
  

3.编写测试类

package com.Jdbc;

import java.sql.Connection;

import javax.sql.DataSource;

import org.junit.Test;

import com.mchange.v2.c3p0.ComboPooledDataSource;


public class C3p0Util {
	 DataSource dataSource = new ComboPooledDataSource();
     @Test
	  public void sd() throws Exception{
    	 Connection connection = dataSource.getConnection();
    	 System.out.println(connection);
    	 
    	 
     }
}

输出连接字符串则表示成功

4.测试通过，封装成c3p0工具类

package com.Jdbc;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.sql.DataSource;


import com.mchange.v2.c3p0.ComboPooledDataSource;


public class C3p0Util {
	 
	 private static DataSource dataSource = new ComboPooledDataSource();
	//获取c3p0连接池连接的方法
	 public static DataSource getDataSource(){
			return dataSource;
	     }
	//获得数据库连接的方法
	 public static Connection getconnection(){
    	Connection connection = null;
		try {
			connection = dataSource.getConnection();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return connection;
     }
	 
    //关闭数据库连接、数据预编译作工具、数据操作读取工具 
 	public void clos(Connection ct,PreparedStatement ps,ResultSet rs){
		if(ct!=null){
			try {
				ct.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		if(ps!=null){
			try {
				ct.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		if(rs!=null){
			try {
				ct.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
}

5.编写查询测试类

package com.util;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.junit.Test;

import com.Jdbc.C3p0Util;


public class TestAll {

	@Test
	public void sad() throws SQLException{
		C3p0Util util = new C3p0Util();
		Connection connection = util.getconnection();
		PreparedStatement ps = connection.prepareStatement("select * from user");
		ResultSet rs = ps.executeQuery();
		while(rs.next()){
			System.out.println(rs.getString("username"));
			System.out.println(rs.getString("password"));
		}
	}
	
}

6.成功输出数据库数据