JAVA entry-level [5]-initial setup of SpringMVC, javaspringmvc

JAVA entry-level [5]-initial setup of SpringMVC, javaspringmvc
1. Create a Module

1. Create a Module, as shown in the following figure:

<Dependency> <groupId> org. springframework </groupId> <artifactId> spring-webmvc </artifactId> <version> 4.3.5.RELEASE </version> </dependency>2. Configure web. xml

Spring MVC comes with a Dispatcher Servlet, whose full name is org. springframework. web. servlet. DispatcherServlet.

1. Configure the node servlet and servlet-mapping in web. xml:

<servlet>  <servlet-name>springmvc</servlet-name>  <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  <load-on-startup>1</load-on-startup></servlet><servlet-mapping>  <servlet-name>springmvc</servlet-name>  <url-pattern>/</url-pattern></servlet-mapping>

2. Description:

• If url-pattern is/, all requests are mapped to DispatcherServlet.
• As agreed, the file named {servletname}-servlet. xml under the WEB-INF is automatically searched at initialization, which corresponds to the springmvc-servlet.xml in this example.

3. If you want to put it in another directory, you need to set the init-param node in the servlet. param-name must be contextConfigLocation, And param-value must be the target path. For example, we want to put the spring configuration file in/WEB-INF/config/springmvc. xml, you can configure as follows:

<servlet>    <servlet-name>springmvc</servlet-name>    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>    <init-param>        <param-name>contextConfigLocation</param-name>        <param-value>/WEB-INF/config/springmvc.xml</param-value>    </init-param>    <load-on-startup>1</load-on-startup></servlet>

In this project, we use the first method.

Iii. controller and view

The MVC framework consists of model, view, and controller. The model is generally a few basic Java Beans. The controller is used to process website requests, and the view is used to display corresponding pages.

1. controller

Create a new package named com. cathy. controller in src \ main \ java, and then create the class CategroyController. java.

@Controllerpublic class CategoryController {    @RequestMapping(value = "/category/edit")    public String Edit() {        return "edit";    }    @RequestMapping("/category/detail")    public String Detail(){        return "detail";    }}

 

Notes:

① @ Controller annotation: The annotation method can be used to clearly define the class as the Controller class for processing requests;

② @ RequestMapping () annotation: used to define a request ing. value is the request url;

③ Return "edit": the page returned after processing the request. The edit. jsp page is returned for this request.

2. view

Create two jsp pages in the WEB-INF/jsp/directory: edit. jsp and detail. jsp

3. Configure springmvc-servlet.xml

Go back to the mvc-dispatcher-servlet.xml for configuration. Add the component-scan label, specify the controller package, and scan the Annotation

<context:component-scan base-package="com.cathy.controller"></context:component-scan><mvc:annotation-driven></mvc:annotation-driven>

Then configure ViewResolver

<!--View Resolver--><bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">    <property name="prefix" value="/WEB-INF/jsp/"/>    <property name="suffix" value=".jsp"/></bean>

3. Problems:

① Running error:

org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'cacheManager' available

② Solution:

Modify springmvc-servlet.xml

xmlns:mvc="http://www.springframework.org/schema/cache

Change

xmlns:mvc="http://www.springframework.org/schema/mvc

Xsi is also modified accordingly

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"

 

③ The complete xml file is as follows:

<? Xml version = "1.0" encoding = "UTF-8"?> <Beans xmlns = "http://www.springframework.org/schema/beans" xmlns: xsi = "http://www.w3.org/2001/XMLSchema-instance" xmlns: context = "http://www.springframework.org/schema/context" xmlns: mvc = "http://www.springframework.org/schema/mvc" xsi: schemaLocation = "http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context h Ttp: // www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd "> <! -- Controller package --> <context: component-scan base-package = "com. cathy. controller"> </context: component-scan> <! -- Enable annotation --> <! -- <Mvc: annotation-driven> </mvc: annotation-driven> --> <! -- View Resolver --> <bean id = "viewResolver" class = "org. springframework. web. servlet. view. internalResourceViewResolver "> <property name =" prefix "value ="/WEB-INF/jsp/"/> <property name =" suffix "value = ". jsp "/> </bean> </beans>Springmvc-servlet.xml 4. Operation

Follow the previous JAVA entry [4]-IntelliJ IDEA to configure Tomcat to Run Configuration, and then Run ctrl + f5 to test the url:

Http: // localhost: 8091/category/detail/

Http: /localhost: 8091/category/edit/