c3p0 连接池使用

1. 导入依赖

  <dependency>
      <groupId>com.mchange</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.2</version>
    </dependency>

2. 编写配置文件

package com.beyond.nothing.utils;

import com.mchange.v2.c3p0.ComboPooledDataSource;

import java.beans.PropertyVetoException;
import java.sql.*;

public class JDBCUtil {
    private static final String USERNAME = "root";
    private static final String PWD = "210374520";
    private static final String URL = "jdbc:mysql://localhost:3308/thedemo";
    private static final String DRIVER = "com.mysql.jdbc.Driver";

    // 使用 c3p0 连接池
    private static final ComboPooledDataSource datasource = new ComboPooledDataSource();

    static {
//        // 注册驱动
//        try {
//            Class.forName(DRIVER);
//        } catch (ClassNotFoundException e) {
//            e.printStackTrace();
//        }
       try {
           datasource.setUser(USERNAME);
           datasource.setPassword(PWD);
           datasource.setJdbcUrl(URL);
           datasource.setDriverClass(DRIVER);
       }catch (PropertyVetoException e){
           e.printStackTrace();
       }

        // 设置最大连接数
        datasource.setMaxPoolSize(10);
        // 设置最低保持的连接数
        datasource.setMinPoolSize(5);

    }


    public static Connection getCoon() throws SQLException {
//        return DriverManager.getConnection(URL,USERNAME,PWD);
        return datasource.getConnection();
    }


    public static void main(String[] args) throws SQLException {
        Connection coon = getCoon();
        System.out.println(coon.toString());
    }

    public static void close(ResultSet resultSet, PreparedStatement preparedStatement, Connection connection) {
        try {
            if (null != resultSet){
                resultSet.close();
            }
            if (null != preparedStatement){
                preparedStatement.close();
            }
            if (null != connection){
                connection.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}