springboot访问页面错误

在学习Spring Security时遇到如下两种错误

错误：Error resolving template [index], template might not exist or might not be accessible by any of the configured
Template Resolvers

错误：Circular view path [index]: would dispatch back to the current handler URL [/index] again. Check your ViewRe
​ solver setup! (Hint: This may be the result of an unspecified view, due to default view name generation.)

自己总结了以下，主要原因有四种

• application.yaml配置问题

  # 关闭模板引擎,配置mvc视图解析器
  spring:
    thymeleaf:
      cache: false
    mvc:
      view:
        suffix: .html
        prefix: classpath:/templates/
  

• thymeleaf启动器问题

   <!-- Thymeleaf依赖 -->
   <dependency>
      <groupId>org.thymeleaf.extras</groupId>
      <artifactId>thymeleaf-extras-java8time</artifactId>
   </dependency>
   <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-thymeleaf</artifactId>
   </dependency>
  

• 静态资源问题

  <build>
          <plugins>
              <plugin>
                  <groupId>org.springframework.boot</groupId>
                  <artifactId>spring-boot-maven-plugin</artifactId>
              </plugin>
          </plugins>
          <resources>
              <resource>
                  <directory>src/main/java</directory>
                  <includes>
                      <include>**/*.xml</include>
                      <include>**/*.XML</include>
                      <include>**/*.yml</include>
                      <include>**/*.html</include>
                  </includes>
              </resource>
              <resource>
                  <directory>src/main/resources</directory>
                  <includes>
                      <include>**/*.xml</include>
                      <include>**/*.XML</include>
                      <include>**/*.yml</include>
                      <include>**/*.html</include>
                  </includes>
              </resource>
          </resources>
      </build>
  

• Handler注解使用错误

  返回字符串注解：@ResponseBody