数据库操作CURD

代码目录结构：

domain javabean；

util 工具类 jdbcUtil是连接数据mysql数据库的工具类

dbcfg.properties是数据库的参数信息

dbcfg.properties

最重要的jdbutil

package com.itheima.util;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.Properties;
public class JdbcUtil {
private static String driverClassName;
private static String url;
private static String username;
private static String password;
static{
//为以上参数赋值
try {
InputStream in = JdbcUtil.class.getClassLoader().getResourceAsStream("dbcfg.properties");
Properties props = new Properties();
props.load(in);
driverClassName = props.getProperty("driverClassName");
url = props.getProperty("url");
username = props.getProperty("username");
password = props.getProperty("password");
Class.forName(driverClassName);//注册驱动
} catch (Exception e) {
throw new RuntimeException(e);
}
}
public static Connection getConnection() throws Exception{
return DriverManager.getConnection(url, username, password);//连接
}
//释放资源
public static void release(ResultSet rs,Statement stmt,Connection conn){
if(rs!=null){
try{
rs.close();
}catch(Exception e){
}
rs=null;
}
if(stmt!=null){
try{
stmt.close();
}catch(Exception e){
}
stmt=null;
}
if(conn!=null){
try{
conn.close();
}catch(Exception e){
}
conn=null;
}
}
}

User实例

数据库操作CURD

JDBCCURD操作实例