org.thymeleaf.exceptions.TemplateInputException: Error resolving template [students/getList], template might not exist or might not be accessible by any of the configured Template Resolvers

原文链接：org.thymeleaf.exceptions.TemplateInputException: Error resolving template [students/getList], template might not exist or might not be accessible by any of the configured Template Resolvers – 每天进步一点点 (longkui.site)

创建调试springboot项目后，然后访问一个接口，控制台开始报错：

Exception processing template "students/getList": Error resolving template [students/getList], template might not exist or might not be accessible by any of the configured Template Resolvers

org.thymeleaf.exceptions.TemplateInputException: Error resolving template [students/getList], template might not exist or might not be accessible by any of the configured Template Resolvers
	at org.thymeleaf.engine.TemplateManager.resolveTemplate(TemplateManager.java:869) ~[thymeleaf-3.0.15.RELEASE.jar:3.0.15.RELEASE]
	at org.thymeleaf.engine.TemplateManager.parseAndProcess(TemplateManager.java:607) ~[thymeleaf-3.0.15.RELEASE.jar:3.0.15.RELEASE]
	at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1098) [thymeleaf-3.0.15.RELEASE.jar:3.0.15.RELEASE]
	at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1072) [thymeleaf-3.0.15.RELEASE.jar:3.0.15.RELEASE]
	at org.thymeleaf.spring5.view.ThymeleafView.renderFragment(ThymeleafView.java:366) [thymeleaf-spring5-3.0.15.RELEASE.jar:3.0.15.RELEASE]
	at org.thymeleaf.spring5.view.ThymeleafView.render(ThymeleafView.java:190) [thymeleaf-spring5-3.0.15.RELEASE.jar:3.0.15.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1405) [spring-webmvc-5.3.24.jar:5.3.24]
	at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1149) [spring-webmvc-5.3.24.jar:5.3.24]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1088) [spring-webmvc-5.3.24.jar:5.3.24]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:964) [spring-webmvc-5.3.24.jar:5.3.24]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) [spring-webmvc-5.3.24.jar:5.3.24]
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) [spring-webmvc-5.3.24.jar:5.3.24]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:670) [tomcat-embed-core-9.0.70.jar:4.0.FR]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) [spring-webmvc-5.3.24.jar:5.3.24]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:779) [tomcat-embed-core-9.0.70.jar:4.0.FR]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) [tomcat-embed-websocket-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) [spring-web-5.3.24.jar:5.3.24]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.24.jar:5.3.24]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) [spring-web-5.3.24.jar:5.3.24]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.24.jar:5.3.24]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) [spring-web-5.3.24.jar:5.3.24]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.24.jar:5.3.24]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:177) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:891) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1784) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.70.jar:9.0.70]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_131]

这个问题的主要原因是Controller层返回的数据没有使用@ResponseBody或者@RestController注解而返回非json类型数据

比如出现错误的一段代码：

@Controller
@RequestMapping("/students")
public class StudentsController {
    @Autowired
    private StudentsService studentsService;
 
    //查询所有
    @GetMapping("/getList")
    public List<HashMap<String,String>> getList(){
        try {
            List<HashMap<String,String>> res = studentsService.getList();
            return res;
        }catch (Exception e){
            e.toString();
            return null;
        }
    }
}