使用JDBC连接MySQL数据库

package com.jason.netctoss.util;

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

import org.apache.tomcat.dbcp.dbcp.BasicDataSource;

public class DBUtil {

//声明连接池
private static BasicDataSource ds;

static{
Properties p = new Properties();
try{
//读取配置文件
p.load(DBUtil.class.getClassLoader().getResourceAsStream("db.properties"));
//数据库连接参数
String driverClassName = p.getProperty("driverClassName");
String url = p.getProperty("url");
String username = p.getProperty("username");
String pwd = p.getProperty("pwd");
//连接池参数
String initialSize = p.getProperty("initialSize");
String maxActive = p.getProperty("maxActive");
//创建连接池，并给它设置参数
ds = new BasicDataSource();
ds.setDriverClassName(driverClassName);
ds.setUrl(url);
ds.setUsername(username);
ds.setPassword(pwd);
ds.setInitialSize(Integer.parseInt(initialSize));
ds.setMaxActive(Integer.parseInt(maxActive));
}catch(IOException e){
e.printStackTrace();
throw new RuntimeException("找不到文件",e);
}
}

//获取连接
public static Connection getConnection() throws SQLException{
return ds.getConnection();
}

//归还连接
public static void close(Connection conn){
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
throw new RuntimeException("归还连接失败",e);
}
}
}

//测试是否访问上了MySQL数据库
public static void main(String[] args) throws SQLException{
Connection conn = DBUtil.getConnection();
System.out.println(conn);
DBUtil.close(conn);
}

}

# db params
driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/admin
username=root
pwd=j****3
#DataSource params
initialSize=4
maxActive=50