为什么我有这种类型的异常？

Question

com.samskivert.mustache.MustacheException$Context: No key, method or field with name 'text' on line 19
    at com.samskivert.mustache.Mustache$VariableSegment.execute(Mustache.java:804) ~[jmustache-1.14.jar:na]
    at com.samskivert.mustache.Mustache$BlockSegment.executeSegs(Mustache.java:845) ~[jmustache-1.14.jar:na]
    at com.samskivert.mustache.Mustache$SectionSegment.execute(Mustache.java:866) ~[jmustache-1.14.jar:na]
    at com.samskivert.mustache.Template.executeSegs(Template.java:157) ~[jmustache-1.14.jar:na]
    at com.samskivert.mustache.Template.execute(Template.java:134) ~[jmustache-1.14.jar:na]
    at org.springframework.boot.web.servlet.view.MustacheView.renderMergedTemplateModel(MustacheView.java:81) ~[spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
    at org.springframework.web.servlet.view.AbstractTemplateView.renderMergedOutputModel(AbstractTemplateView.java:165) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:314) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1325) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1069) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1008) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:978) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:870) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:855) ~[spring-webmvc-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109) ~[spring-web-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) ~[spring-web-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.4.RELEASE.jar:5.0.4.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) ~[tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_211]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_211]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.28.jar:8.5.28]
    at java.lang.Thread.run(Thread.java:748) [na:1.8.0_211]

和

@Controller
public class GreetingController {
    @Autowired
    private MessageRepo messageRepo;

    @GetMapping("/greeting")
    public String greeting(
            @RequestParam(name="name", required=false, 
defaultValue="World") String name,
            Map<String, Object> model
    ) {
        model.put("name", name);
        return "greeting";
@GetMapping
public String main(Map<String, Object> model) {
    Iterable<Message> messages = messageRepo.findAll();

    model.put("messages", messages);

    return "main";
}

@PostMapping
public String add(@RequestParam String text, @RequestParam String tag, Map<String, Object> model) {
    Message message = new Message(text, tag);

    messageRepo.save(message);

    Iterable<Message> messages = messageRepo.findAll();

    model.put("messages", messages);

    return "main";
}

@PostMapping("filter")
public String filter(@RequestParam String filter, Map<String, Object> model) {
    Iterable<Message> messages;

    if (filter != null && !filter.isEmpty()) {
        messages = messageRepo.findByTag(filter);
    } else {
        messages = messageRepo.findAll();
    }

    model.put("messages", messages);

    return "main";
}
}

和

@Entity
public class Message {
@Id
@GeneratedValue(strategy= GenerationType.AUTO)
private Integer id;

private String text;
private String tag;

public Message() {
}

public Message(String text, String tag) {
    this.text = text;
    this.tag = tag;
}

public void setText(String text) {
    this.text = text;
}

public String getText() {
    return text;
}

public Integer getId() {
    return id;
}

public void setId(Integer id) {
    this.id = id;
}

public String getTag() {
    return tag;
}

public void setTag(String tag) {
    this.tag = tag;
 }
}

和

<html>

<body>
<div>
    <form method="post">
        <input type="text" name="text" placeholder="Введите сообщение" />
        <input type="text" name="tag" placeholder="Тэг">
        <button type="submit">Добавить</button>
    </form>
</div>
<div>Список сообщений</div>
<form method="post" action="filter">
    <input type="text" name="filter">
    <button type="submit">Найти</button>
</form>
{{#messages}}
    <div>
        <b>{{id}}</b>
        <span>{{text}}</span>
        <i>{{tag}}</i>
    </div>
{{/messages}}
</body>
</html>