<!--設(shè)置打包方式為war-->
<packaging>war</packaging>

<!-- 添加springmvc依賴 -->
<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-webmvc</artifactId>
  <version>5.3.18</version>
</dependency>
<!-- 添加servlet 依賴 -->
<dependency>
  <groupId>javax.servlet</groupId>
  <artifactId>javax.servlet-api</artifactId>
  <version>4.0.1</version>
  <scope>provided</scope>
</dependency>

package org.example.Controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
    public class UserController {

        @RequestMapping("/save")
        @ResponseBody
        public String index() {
            return "index";
        }
    }

@Configuration
@ComponentScan("org.example.Controller")
//掃描Controller包
public class SpringMvcConfig {
}

package org.example.Config;

import org.example.Config.SpringMvcConfig;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.support.AbstractDispatcherServletInitializer;

//定義一個servelt容器啟動的配置類,用于加載spring的配置類
public class SpringMvcInit  extends AbstractDispatcherServletInitializer {


    //1. 將controller層放在springmvc容器中,其他如service層放在父容器,bean管理起來更清晰
    //2. 也可以沒有父容器，將所有bean都放在springmvc容器中
    @Override
    //加載springMVC容器的配置類
    protected WebApplicationContext createServletApplicationContext() {
        //創(chuàng)建SpringMVC容器
        AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();
        //加載配置類--SpringMvcConfig
        ctx.register(SpringConfig.class);
        return ctx;

    }

    @Override
    //配置哪些請求要被攔截,歸屬SpringMVC處理
    // /: 攔截所有請求
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }

    @Override
    //加載Spring容器的配置類
    protected WebApplicationContext createRootApplicationContext() {
        return null;
    }
}

public class SpringMvcInit  extends AbstractAnnotationConfigDispatcherServletInitializer {

    //1. 將controller層放在springmvc容器中,其他如service層放在父容器,bean管理起來更清晰
    //2. 也可以沒有父容器，將所有bean都放在springmvc容器中
    // === 上面的createRootApplicationContext()做的事
    //用來加載  springmvc容器的父容器spring的配置類
    @Override
    protected Class<?>[] getRootConfigClasses() {
        return new Class[0];
    }

    //加載springMVC的配置類
    //=== 上面的createServletApplicationContext()做的事
    @Override
    protected Class<?>[] getServletConfigClasses() {
        return new Class[]{SpringConfig.class};
    }

    //配置哪些請求要被攔截,歸屬SpringMVC處理
    // /: 攔截所有請求
    @Override
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }

}