java 简单的数据增删该查

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


public class test {
	public static void main(String[] args) {
	
		System.out.println("aaa");
		try {
		String url = "jdbc:mysql://localhost:3306/demo1?"
              + "user=root&password=root&useUnicode=true&characterEncoding=UTF8";
			Class.forName("com.mysql.jdbc.Driver");
		
			Connection con=	DriverManager.getConnection(url);
//			创建查询
			Statement st=con.createStatement();
//			添加数据
			String sqlAdd="insert into student(sname,spass) values(‘掌柜的‘,‘1236547‘)";
			int add=st.executeUpdate(sqlAdd);
			if(add!=0)
			{
				System.out.println("添加数据成功！");
			}
//			删除数据
			String sqlDel="delete from student where sid=2";
			int del=st.executeUpdate(sqlDel);
			if(del!=0)
			{
				System.out.println("删除成功！");
			}
//		更新数据
		String sqlUpdate="update student set sname=‘战鹰‘ where sname=‘wanghu‘";
		int a=	st.executeUpdate(sqlUpdate);
//		判断是否更新成功
		if(a!=0)
		{
			System.out.println("修改成功");
		}
//		查询结果
		String sqlSelect="select * from student";
			ResultSet rs=	st.executeQuery(sqlSelect);
			while(rs.next())
			{
				int id=rs.getInt("sid");
				String name=rs.getString("sname");
				String pass=rs.getString("spass");
				System.out.println("id="+id+",  name="+name+", pass="+pass);
			}
		} catch (Exception e) {
			e.printStackTrace();
			System.out.println(e.getMessage());
		}
	}
}