Spring实战——Bean的作用域request

冷不防 2021-07-25 01:01 414阅读 0赞

**一 配置**

1 applicationContext.xml

<?xml version="1.0" encoding="GBK"?>
    <beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns="http://www.springframework.org/schema/beans"
        xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-4.0.xsd">
        
        <bean id="p" class="org.crazyit.app.service.Person"
            scope="request"/>
    </beans>

2 web.xml

<?xml version="1.0" encoding="GBK"?>
    <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
        http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" version="3.1">
        <listener>
            <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
        </listener>
        <listener>
            <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
        </listener>
    </web-app>

**二 Bean**

package org.crazyit.app.service;
    
    public class Person
    {
        private int age;
    }

**三 视图**

<%@ page contentType="text/html; charset=GBK" language="java" errorPage="" %>
    <%@ page import="org.springframework.web.context.*" %>
    <%@ page import="org.springframework.web.context.support.*" %>
    <%@ page import="org.crazyit.app.service.*"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title>Spring Bean的作用域</title>
    </head>
    <body>
    <%
    // 获取Web应用初始化的Spring容器
    WebApplicationContext ctx =
        WebApplicationContextUtils.getWebApplicationContext(application);
    // 两次获取容器中id为p的Bean
    Person p1 = (Person)ctx.getBean("p");
    Person p2 = (Person)ctx.getBean("p");
    out.println((p1 == p2) + "<br/>");
    out.println(p1);
    %>
    </body>
    </html>

**四 测试**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70]: /images/20210724/0b95e1962751479a8af4d23940e8bd6e.png