JDBC-API详解-ResultSet

package Test;

import org.junit.Test;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class JDBCdemo4_ResultSet {
    @Test
    public void testResultSet() throws Exception {//DQL查询语句
        //1.注册驱动
        //Class.forName("com.mysql.jdbc.Driver");
        //2.获取连接
        String url = "jdbc:mysql:///test?useSSL=false";
        String username = "root";
        String password = "1234";
        Connection conn = DriverManager.getConnection(url, username, password);
        //3.定义sql
        String sql="select * from test";
        //4.获取statement对象
        Statement stmt = conn.createStatement();
        //5.执行sql
        ResultSet rs = stmt.executeQuery(sql);
        //6.处理结果，遍历rs中所有的数据
        //6.1光标向下移动一行，并且判断当前行是否有数据
        /*while (rs.next()){
            //6.2获取数据 getXxx()
            int id = rs.getInt(1);
            String name = rs.getNString(2);
            double money = rs.getDouble(3);

            System.out.println(id);
            System.out.println(name);
            System.out.println(money);
            System.out.println("--------------------");
        }*/
        //第二种写法
        while (rs.next()){
            //6.2获取数据 getXxx()
            int id = rs.getInt("id");
            String name = rs.getNString("name");
            double money = rs.getDouble("money");

            System.out.println(id);
            System.out.println(name);
            System.out.println(money);
            System.out.println("--------------------");
        }
        //7.释放资源
        rs.close();
        stmt.close();
        conn.close();
    }

}