java 简单jdbc

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

/**
*  @author ny
*  @Drecisption  jdbc 工具类
*/

public class DBconn {

Connection con = null;
static DBconn db = null;

/**
* @param DBdriver 驱动路径
*/
public static final String DBdriver = "com.mysql.jdbc.Driver";
/**
* @param DBurl 数据库连接地址
*/
public static final String DBurl = "jdbc:mysql://localhost:3306/bookstore";
/**
* @param DBusre 数据库用户名
*/
public static final String DBusre = "root";
/**
* @param DBpwd 数据库密码
*/
public static final String DBpwd = "123456";
/**
* @param 加载驱动类
*/
static{
try {
Class.forName(DBdriver);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
/**
*
* 私有化构造函数
*
*/
private DBconn(){}
/**
* @param 单例模式下获取实例或者抽象类获得子类
* @return db 实例
*/
public static DBconn getInstence(){
if(db==null){
db = new DBconn();
}
return db;
}
/**
* 获得数据库连接
* @return 数据库连接
*/

public  Connection getConnection(){
try {
con = DriverManager.getConnection(DBurl, DBusre, DBpwd);
} catch (SQLException e) {
e.printStackTrace();
}
return con;
}
/**
* 关闭连接
*/
public void closeConnection(){
try {
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}

}