package cn.hncu;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Scanner;
import java.util.UUID;
import org.junit.Test;
import cn.hncu.pubs.ConnFactory;
public class JdbcDemo {
	
	//查
	@Test
	public void readDemo() throws Exception{
		Class.forName("com.mysql.jdbc.Driver");//驱动 ---jdbc4.0开始,这一句可以省略。
		//hibernate框架,上一句不要省。 
		
		String url = "jdbc:mysql://127.0.0.1:3306/hncu?useUnicode=true&characterEncoding=utf-8";//hncu这个是你要使用账号登陆数据库3306是你数据库的接
口;
		Connection con = DriverManager.getConnection(url,"root","1234");
		//System.out.println(con);
		Statement st = con.createStatement();
		ResultSet rs = st.executeQuery("select * from person2"); //该方法专用于查询
		while(rs.next()){
			String id0 = rs.getString(1);
			Object id = rs.getObject(1);//字段序号
			Object nm = rs.getObject("name"); //字段名
			String ch = rs.getString(3);
			if(ch.trim().equals("0")){
				ch="女";
			}else if(ch.trim().equals("1")){
				ch="男";
			}else{
				ch="未知";
			}		
			System.out.println(id0+"-"+id+","+nm+","+ch);
		}
		
		con.close();
	}
	
	//增
	@Test
	public void saveDemo() throws Exception{
		Connection con = ConnFactory.getConn();
		Scanner sc = new Scanner(System.in);
		String name = sc.nextLine();
		
		//增
		//String uuid = UUID.randomUUID().toString().replace("-", "");
		//String sql = "INSERT INTO person2 VALUES(‘"+uuid+"‘,‘"+name+"‘,‘1‘)";
		//INSERT INTO person2 VALUES(‘P09‘,‘赵子龙‘,‘1‘);
		
		//改
		//String sql = "UPDATE person2 SET NAME = CONCAT(NAME,‘"+name+"‘) WHERE LENGTH(id)<4";
		//UPDATE person2 SET NAME = CONCAT(NAME,"x") WHERE LENGTH(id)<4;
		
		//删
		String sex="0";
		String sql = "delete from person2 where sex=‘"+sex+"‘";
		//delete from person2 where sex=‘0‘;
		
		System.out.println("sql: "+ sql);
		
		Statement st  = con.createStatement();
		int a = st.executeUpdate(sql); //该方法一般用于如下操作:增insert、删delete、改update  
		//上面方法的返回值: 影响的行数
		System.out.println("影响的行数:"+a);
		con.close();
	}
}
原文:http://www.cnblogs.com/1314wamm/p/6044687.html