JavaWeb-JavaBean

一、JavaBean

实体类

  • JavaBean有特定的写法：
    • 必须要有一个无参构造
    • 属性必须私有化
    • 必须有对应的 get/set方法

一般用来和数据库的字段做映射 ORM；

  • ORM：对象关系映射
    • 表 --> 类
    • 字段 --> 属性
    • 行记录 --> 对象

实体类

package com.kuang.pojo;

public class People {

	private int id;
	private String name;
	private int age;
	private String address;



	public People() {
	}
	public People(int id, String name, int age, String address) {
		super();
		this.id = id;
		this.name = name;
		this.age = age;
		this.address = address;
	}
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	
	@Override
	public String toString() {
		return "People [id=" + id + ", name=" + name + ", age=" + age + ", address=" + address + "]";
	}

}

index.jsp

<%@page import="com.kuang.pojo.People"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
   
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>

<%
// 原型

// People people = new People();
// people.setAddress("西安");
// people.setId(1);
// people.setAge(3);
// people.setName("小狂神");
%>

<%-- 使用一个对象 --%>
<%--		变量名	   class的路径  作用域 --%>
<jsp:useBean id="people" class="com.kuang.pojo.People" scope="page" />

<jsp:setProperty name="people" property="address" value="西安"/>
<jsp:setProperty name="people" property="id" value="1"/>
<jsp:setProperty name="people" property="age" value="3"/>
<jsp:setProperty name="people" property="name" value="小狂神"/>

姓名：<jsp:getProperty property="name" name="people"/>
id：<jsp:getProperty property="id" name="people"/>
年龄：<jsp:getProperty property="age" name="people"/>
地址：<jsp:getProperty property="address" name="people"/>

</body>
</html>
posted @ 2021-02-21 09:43  魍  阅读(51)  评论(0)    收藏  举报