【Java】最簡單的jdbc連接查詢

package com.demo.ten;

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

import org.junit.Test;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
/**
 * jdbc 連接數據庫進行查詢
 * @author root
 * @date 2016年11月8日
 */
public class Test1 {
	
	public static final String url = "jdbc:mysql://127.0.0.1/learn";
	public static final String driver = "com.mysql.jdbc.Driver";
	public static final String user = "root";
	public static final String password = "root";
	
	//聲明連接對象
	public Connection conn = null;
	//聲明執行對象
	PreparedStatement ps = null;
	//聲明結果集對象
	ResultSet rs = null;
	@Test
	public void test1() throws ClassNotFoundException, SQLException{
		//顯示加載驅動類
		Class.forName(driver);
		//獲取連接對象
		conn = DriverManager.getConnection(url, user, password);
		//獲取執行對象
		ps = conn.prepareStatement("select * from user");
		//獲取結果集對象
		rs = ps.executeQuery();			
		while(rs.next()){
			//輸出
			System.out.println(rs.getInt("id")+" "+rs.getString("username")+" "+rs.getString("password"));
		}
		
	}
}