解决idea中SpringBoot整合jsp页面时访问不到页面的问题

一、问题说明

SpringBoot整合jsp页面时，遇到访问不到页面的问题，如下图。下面介绍解决方法。

二、搭建一个springboot项目，使用jsp作为页面显示

具体步骤如下：

1. 创建一个空的maven项目

按下图步骤创建，最后 Finish

2. 添加maven依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>springboot-web</artifactId>
    <version>1.0-SNAPSHOT</version>


    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
    </parent>

    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <!-- SpringBoot web 核心组件 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- JSTL for JSP -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
        </dependency>

        <!-- SpringBoot 外部tomcat支持 -->
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
        </dependency>

        <!-- JSON 支持 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.47</version>
        </dependency>
    </dependencies>

</project>

3. 创建application.yml配置文件

server:
  port: 8080
  tomcat:
    uri-encoding: utf-8
  servlet:
    jsp:
      init-parameters: { development: true } # jsp热加载

spring:
  mvc:
    view:
      suffix: .jsp
      prefix: /WEB-INF/views/
  http:
    encoding:
      charset: UTF-8
      enabled: true
      force: true
logging:
  level:
    root: info

4. 创建启动类HelloApi.java

package com.rain.a.api;

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

@Controller
public class HelloApi {

    @RequestMapping("/hello")
    public String hello(){
        return "hello";
    }
}

5. 创建webapp和WEB-INF目录，并将webapp目录设置为web页面目录

webapp和WEB-INF目录的位置如下图：

设置webapp目录：

6. 创建jsp文件

在webapp/WEB-INF/views/目录下创建hello.jsp文件

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Hello World</title>
</head>
<body>
<h1>Hello World !</h1>
</body>
</html>

7. 创建controller层

package com.example.controller;

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

@Controller
public class HelloController {
    @RequestMapping("/hello")
    public String hello(){
        return "hello";
    }
}