JDBC工具类抽取方式一（测试根据id查询）

package cn.itheima.jdbc;
/**
* 提供获取连接和释放资源的方法
* @author XING
*
*/

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

public class JDBCUtils_V1 {
/**
* 获取连接方法
*
* @return
*/
public static Connection getConnection(){
Connection conn = null;
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/web08", "root", "root");
} catch (Exception e) {
e.printStackTrace();
}
return conn;
}

public static void release(Connection conn, PreparedStatement pstmt, ResultSet rs){
if (rs !=null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (pstmt !=null) {
try {
pstmt.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(conn !=null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}

package cn.itheima.jdbc.test;

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

import org.junit.Test;

import cn.itheima.jdbc.JDBCUtils_V1;

/**
* 测试工具类
*
* @author XING
*
*/
public class TestUtils {

/**
* 根据id查询用户信息
*/
@Test
public void testFindUserById(){
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try {
//1.获取连接
conn = JDBCUtils_V1.getConnection();
//2.编写SQL语句
String sql = "select * from tbl_user where uid=?";
//3.获取执行SQL语句对象
pstmt = conn.prepareStatement(sql);
//4.设置参数
pstmt.setInt(1, 2);
//5.执行查询操作
rs = pstmt.executeQuery();
//6.处理结果集
while(rs.next()){
System.out.println(rs.getString(2)+"----"+rs.getString("upassword"));
}
//释放资源能放在此处行么？【不行滴！】

} catch (Exception e) {
e.printStackTrace();
}finally{
//7.释放资源
JDBCUtils_V1.release(conn, pstmt, rs);
}
}
}