SpringMVC-02 HandlerMapping的常见种类及注解

Posted 2022-09-28 dt-demo

目录

• HandlerMapping的常见种类
  • BeanNameUrlHandlerMapping
  • SimpleUrlHandlerMapping
  • ControllerClassNameHandlerMapping
• 使用注解替代配置

HandlerMapping的常见种类

HandleMapping:处理映射器,可以理解为为请求的url查找对应的Controller类.

BeanNameUrlHandlerMapping

根据bean标签的名称找到对应的Controller类。

SimpleUrlHandlerMapping

根据bean的id查找对应的Controller类。

ControllerClassNameHandlerMapping

根据controller类的名字找到对应的Controller。

使用注解替代配置

引入指定jar

1.包扫描：扫描注解所在包
2.开启注解标签：Annotation

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" 
?????xmlns:mvc="http://www.springframework.org/schema/mvc"
?????xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
?????xmlns:context="http://www.springframework.org/schema/context"
?????xsi:schemaLocation="http://www.springframework.org/schema/beans 
       ?http://www.springframework.org/schema/beans/spring-beans.xsd
????????http://www.springframework.org/schema/context
??????? http://www.springframework.org/schema/context/spring-context.xsd
??????? http://www.springframework.org/schema/mvc
??????? http://www.springframework.org/schema/mvc/spring-mvc.xsd">
?????<!-- 包扫描 -->
?????<context:component-scan base-package="com.hw.lb.controller.annotation"></context:component-scan>
?????<!-- 启动注解器 -->
?????<mvc:annotation-driven/>????
?????<!-- 配置视图解析器 -->
? ????<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
? ?????????<property name="prefix" value="/WEB-INF/view/"/>
? ?????????<property name="suffix" value=".jsp"/>
? ????</bean>
</beans>

3.创建Controller类（在类中添加Controller注解,可以创建多个方法）

package com.hw.lb.controller.annotation;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
@Controller
public class FirstAnnotation 
?????@RequestMapping("/list.do")
?????public String list() 
???????????System.out.println("查询所有");
???????????return "login";
?????