Spring Boot 本地部署 JSP

自己是Spring Boot 的初学者，开始看教程的时候发现基本上都是部署的 JSP，但是按照教程一步步走下来始终无法成功，一直都是 404:
在这里插入图片描述

查阅各种资料后，总结出一套 Spring Boot 支持 JSP 的流程：

添加依赖

在pom.xml中添加两个依赖：tomcat-embed-jasper（它提供了JSP解析和执行的功能）和 javax.servlet-api（它提供了对 JSP 所需的 Servlet API 的支持）。这是所需的 pom.xml内容：

        <dependency><groupId>org.apache.tomcat.embed</groupId><artifactId>tomcat-embed-jasper</artifactId><scope>provided</scope></dependency><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>3.1.0</version><scope>provided</scope></dependency>

要注意的是，将 pom.xml 文件的 packing 方式修改为 war:

    <packaging>war</packaging>

配置主类

配置 SpringBootServletInitializer 子类以启用 JSP 支持。

package com.example.springfirst;import org.springframework.boot.SpringApplication;
import org.springframework.boot.actuate.autoconfigure.wavefront.WavefrontProperties;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;@SpringBootApplication
public class SpringFirstApplication extends SpringBootServletInitializer {@Overrideprotected SpringApplicationBuilder configure(SpringApplicationBuilder application) {return application.sources(WavefrontProperties.Application.class);}public static void main(String[] args) {SpringApplication.run(SpringFirstApplication.class, args);}}

常规内容

其它的配置，比如 mapping 应该和网上的一致，我就简单记录一下。

package com.example.springfirst.spittr.config;import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;@Configuration
@ComponentScan(basePackages={"com.example.springfirst.spittr"})
public class RootConfig {
}

package com.example.springfirst.spittr.config;import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
import com.example.springfirst.spittr.web.WebConfig;public class SpitterWebInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {@Overrideprotected String[] getServletMappings() {return new String[] { "/" };}@Overrideprotected Class<?>[] getRootConfigClasses() {return new Class<?>[] { RootConfig.class };}@Overrideprotected Class<?>[] getServletConfigClasses() {return new Class<?>[] { WebConfig.class };}}

package com.example.springfirst.spittr.web;import static org.springframework.web.bind.annotation.RequestMethod.*;import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;import javax.annotation.PostConstruct;@Controller
public class HomeController {@PostConstructpublic void init() {System.out.println("HomeController bean created");}@RequestMapping(value="/home", method = GET)public String home() {return "home";}}

package com.example.springfirst.spittr.web;import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import org.springframework.web.servlet.view.InternalResourceViewResolver;@Configuration
@EnableWebMvc
@ComponentScan("com.example.springfirst.spittr.web")
public class WebConfig implements WebMvcConfigurer {@Beanpublic ViewResolver viewResolver() {InternalResourceViewResolver resolver = new InternalResourceViewResolver();resolver.setPrefix("/WEB-INF/jsp/");resolver.setSuffix(".jsp");return resolver;}//    @Override
//    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
//        configurer.enable();
//    }
}