DBCP 连接池的使用

1、配置文件

db.properties

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/web08?useUnicode=true&characterEncoding=utf8
username=root
password=root

2、DBCP连接池 获取连接

DBCPUtils.java

package cn.itheima.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 {
            //1.加载找properties文件输入流
            InputStream is = DBCPUtils.class.getClassLoader().getResourceAsStream("db.properties");
            //2.加载输入流
            Properties props = new Properties();
            props.load(is);
            //3.创建数据源
            dataSource = BasicDataSourceFactory.createDataSource(props);
        } 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);
        }
    }
}

3、测试类

TestDBCP.java

package cn.itheima.jdbc.test;

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

import org.junit.Test;

import cn.itheima.jdbc.utils.DBCPUtils;

public class TestDBCP {

    @Test
    public void testUpdateUserById(){
        Connection conn = null;
        PreparedStatement pstmt = null;
        try {
            conn = DBCPUtils.getConnection();
            String sql ="update tbl_user set upassword=? where uid=?";
            pstmt= conn.prepareStatement(sql);
            pstmt.setString(1, "柳岩");
            pstmt.setInt(2, 20);
            int rows = pstmt.executeUpdate();
            if(rows>0){
                System.out.println("更新成功!");
            }else{
                System.out.println("更新失败!");
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}