JDBC连接池(三)DBCP连接池

JDBC连接池(三)DBCP连接池

在前面的随笔中提到 了  1.JDBC自定义连接池  2.　C3P0连接池

今天将介绍DBCP连接池

第一步要导入jar包   (注意：mysql和mysql 驱动的版本问题  ，驱动过低会造成下图异常)

创建db.properties 配置文件

DBCPUtils.java 文件

 package com.study.jdbc.Utils;

 import java.io.InputStream;
 import java.sql.Connection;
 import java.sql.SQLException;
 import java.util.Properties;

 import javax.sql.DataSource;

 import org.apache.commons.dbcp.BasicDataSourceFactory;

 public class DBCPUtils {

     private static DataSource dataSource;
     static{

         try {
             InputStream is=DBCPUtils.class.getClassLoader().getResourceAsStream("db.properties");
             Properties props=new Properties();
             props.load(is);
             //创建数据源
             System.out.println(props.getProperty("driver"));
             dataSource=BasicDataSourceFactory.createDataSource(props);
             System.out.println(dataSource);
         } catch (Exception e) {
             throw new RuntimeException(e);
         }

     }
     public static DataSource getDataSource(){
         return dataSource;
     }
     public static Connection getConnection(){

         try {
             return dataSource.getConnection();
         } catch (SQLException e) {
             throw new RuntimeException(e);
         }
     }
 }

TestDBCP.java

package cn.itheima.jdbc.test;

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

import org.junit.Test;

import cn.itheima.jdbc.utils.DBCPUtils;

public class TestDBCP {

    @Test
    public void test1(){
        Connection conn=null;
        PreparedStatement pstm=null;
        ResultSet rs=null;
        try {
            conn=DBCPUtils.getConnection();
            String sql="select * from user";
            pstm=conn.prepareStatement(sql);
            rs=pstm.executeQuery();
            while(rs.next()){
                System.out.print(" userId ="+rs.getObject("userId")+"   ");
                System.out.println(" userName ="+rs.getObject("userName"));

            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

    }

    public static void main(String[] args) {
        Connection conn=null;
        PreparedStatement pstm=null;
        ResultSet rs=null;
        try {
            conn=DBCPUtils.getConnection();
            String sql="select * from user";
            pstm=conn.prepareStatement(sql);
            rs=pstm.executeQuery();
            while(rs.next()){
                System.out.print(" userId ="+rs.getObject("userId")+"   ");
                System.out.println(" userName ="+rs.getObject("userName"));

            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

    }
}