package com.java.test1;
import java.security.interfaces.RSAKey;
import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.omg.PortableServer.ID_ASSIGNMENT_POLICY_ID;
public class JdbcTest2 {
public static void main(String[] args) {
Connection connection = null;
Statement st = null;
ResultSet resultSet = null;
//Driver driver =
//1.注册驱动
try {
DriverManager.registerDriver(new com.mysql.jdbc.Driver());
//建立连接 参数一 参数二 参数三
connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/student1", "root", "root");
connection.createStatement();
// 3创建statement,和数据库打交道一定需要这个对像
st = connection.createStatement();
//4查询
String sql = "select *from list";
resultSet = st.executeQuery(sql);
while(resultSet.next()){
int id = resultSet.getInt("id");
String name = resultSet.getString("name");
String age = resultSet.getString("age");
//输出的上面变量接收的返回值
System.out.println("id="+id+"name="+name+"age="+age);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
//第五步骤是严格按照jdbc的api格式进行书写代码的
}finally {
//5.释放order 按照顺序进行释放
if(resultSet != null){
try {
resultSet.close();
}
catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
resultSet = null;
}
if(st != null ){
try {
st.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
st = null;
}
if(connection != null){
try {
connection.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
connection = null;
}
}
}
}