遍历 Hashmap [Springboot、MVC、Java、Thymeleaf]
Posted
技术标签:
【中文标题】遍历 Hashmap [Springboot、MVC、Java、Thymeleaf]【英文标题】：Iterate through Hashmap [Springboot, MVC, Java, Thymeleaf ] 【发布时间】：2017-03-29 18:49:02 【问题描述】：今天我改善了我的库存。我不再使用 LinkedList，现在我使用的是 HashMap。因为使用 LinkedList 我无法删除开始和结束之间的值。 现在使用 Hashmap，可以创建和删除新条目（在控制台中，我总是在打印 hashmap（如果它充满了新条目）） 所以它的工作。但是 Thymeleaf 现在在 for-each 循环中给了我一个 Whitelabel-Error：
"There was an unexpected error (type=Internal Server Error, status=500).
Exception evaluating SpringEL expression: "entry.key" (stock:23)"
那是我的 Stock.html（我认为错误必须在 for-each 循环中）
<div id="overall">
<h1>Lagerübersicht</h1>
<div id="left">
<table id="invoverview" border="1">
<caption>Bestand</caption>
<thead>
<tr>
<th>Produktbezeichnung</th>
<th>Anzahl</th>
</tr>
</thead>
<tbody>
<!-- th:each="entry : $entries" -->
<tr th:each="entry : $entries" >
<td th:text="$entry.key">H</td> <!--something wrong here-->
<td th:text="$entry.value">A</td><!--something wrong here-->
</tr>
</tbody>
</table>
</div>
<div id="right">
<div>
<form name="entry" action="entry" method="POST">
<h3>Neuer Lagereintrag:</h3>
<label>Produktbezeichnung <input id="ProductName" name="ProductName" /></label><br/>
<label>Produktanzahl <input id="ProductAmount" name="ProductAmount" /></label><br/>
<button type="submit" href="/entry">Einfügen</button>
</form>
</div>
<div>
<form name="delentry" action="delentry" method="POST">
<h3>Lagereintrag Löschen:</h3>
<label>Produktbezeichnung <input id="ProductName" name="ProductName" /></label><br />
<label>Produktmenge <input id="ProductAmount" name="ProductAmount" /></label><br />
<button type="submit" href="/delentry">Entfernen</button>
</form>
</div>
</div>
还有我的 StockController.java：
@RequestMapping("/")
public String index(Model model)
model.addAttribute("entries", products); //maybe an error?
return "stock";
@RequestMapping(value ="/entry", method = RequestMethod.POST)
public String setNewEntry(Model model,
@RequestParam("ProductName") String productname,
@RequestParam("ProductAmount") Integer productamount)
System.out.println(productname);
System.out.println(productamount);
products.newEntry(productname,productamount);
model.addAttribute("entries", products);
return "stock";
@RequestMapping(value ="/delentry", method = RequestMethod.POST)
public String delEntry(Model model,
@RequestParam("ProductName") String productname,
@RequestParam("ProductAmount") Integer productamount)
products.delEntry(productname,productamount);
System.out.println(productname);
System.out.println(productamount);
model.addAttribute("entries", products); //error too, idk?
return "stock";
Stock.java：
//private HashMap<StockEntry, Stock> entries;
public Map<String, Integer> entries = new HashMap<String, Integer>();
//private HashMap entries = new HashMap(productname,productamount);
public Stock()
//this.key = 0;
this.productname = null;
this.productamount = 0;
this.entries = new HashMap<String, Integer>();
public Map getEntries()
return this.entries;
public void newEntry(String productname, Integer productamount)
//StockEntry entry = new StockEntry(productname, productamount);
//entries.putIfAbsent(productname,productamount);
entries.put(productname, productamount);
/*if(entries.containsKey(productname))
entries.put(productname, productamount + productamount2);
else
entries.put(productname,productamount2);
*/
System.out.println(entries);
/*for (StockEntry bla : this.entries)
System.out.println(bla.getProductname());
System.out.println(bla.getProductamount());
*/
public void delEntry(String productname, Integer productamount)
entries.remove(productname);
System.out.println(entries);
还有我的初始化器（这里是创建的产品）：
@Component
Public class ApplicationInitalizer implements DataInitializer
private Stock products;
@Autowired
public ApplicationInitalizer(Stock products)
Assert.notNull(products, "should not be null");
this.products = products;
@Override
public void initialize()
initializeStock();
private void initializeStock()
products.newEntry("Kastenbier", 50); //beer
products.newEntry("Kastenwasser", 5);
products.newEntry("Kastencola", 500);
products.newEntry("Schnaps", 50000); //
products.newEntry("Döner", 9);
如果我们/您发现错误，我会非常高兴。因为今天早些时候它已经工作了。这令人困惑，不知何故我设法删除了 StockController.java 代码的一些行，现在我现在不知道我之前是如何和朋友们一起做的了。（它已经工作了，并且在某个点值（´ productamount`) 在表格中消失了）。
也许控制台输出有帮助：
2016-11-15 19:19:45.312 ERROR 16276 --- [nio-8080-exec-1] org.thymeleaf.TemplateEngine : [THYMELEAF][http-nio-8080-exec-1] Exception processing template "stock": Exception evaluating SpringEL expression: "entry.key" (stock:23)
2016-11-15 19:19:45.312 ERROR 16276 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.thymeleaf.exceptions.TemplateProcessingException: Exception evaluating SpringEL expression: "entry.key" (stock:23)] with root cause
org.springframework.expression.spel.SpelEvaluationException: EL1008E:(pos 6): Property or field 'key' cannot be found on object of type 'kickstart.model.Stock' - maybe not public?
at org.springframework.expression.spel.ast.PropertyOrFieldReference.readProperty(PropertyOrFieldReference.java:224) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.expression.spel.ast.PropertyOrFieldReference.getValueInternal(PropertyOrFieldReference.java:94) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.expression.spel.ast.PropertyOrFieldReference.access$000(PropertyOrFieldReference.java:46) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.expression.spel.ast.PropertyOrFieldReference$AccessorLValue.getValue(PropertyOrFieldReference.java:374) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:88) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.expression.spel.ast.SpelNodeImpl.getValue(SpelNodeImpl.java:120) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:267) ~[spring-expression-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.thymeleaf.spring4.expression.SpelVariableExpressionEvaluator.evaluate(SpelVariableExpressionEvaluator.java:139) ~[thymeleaf-spring4-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.standard.expression.VariableExpression.executeVariable(VariableExpression.java:154) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.standard.expression.SimpleExpression.executeSimple(SimpleExpression.java:59) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.standard.expression.Expression.execute(Expression.java:103) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.standard.expression.Expression.execute(Expression.java:133) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.standard.expression.Expression.execute(Expression.java:120) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.standard.processor.attr.AbstractStandardTextChildModifierAttrProcessor.getText(AbstractStandardTextChildModifierAttrProcessor.java:68) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.processor.attr.AbstractTextChildModifierAttrProcessor.getModifiedChildren(AbstractTextChildModifierAttrProcessor.java:59) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.processor.attr.AbstractChildrenModifierAttrProcessor.processAttribute(AbstractChildrenModifierAttrProcessor.java:59) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.processor.attr.AbstractAttrProcessor.doProcess(AbstractAttrProcessor.java:87) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.processor.AbstractProcessor.process(AbstractProcessor.java:212) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.applyNextProcessor(Node.java:1017) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:972) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.dom.Document.process(Document.java:93) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1155) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1060) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1011) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.spring4.view.ThymeleafView.renderFragment(ThymeleafView.java:335) ~[thymeleaf-spring4-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.thymeleaf.spring4.view.ThymeleafView.render(ThymeleafView.java:190) ~[thymeleaf-spring4-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1257) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1037) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:980) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:622) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:115) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:169) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter.doFilter(DefaultLoginPageGeneratingFilter.java:177) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:121) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:66) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:89) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:108) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:784) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:802) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1410) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.5.jar:8.5.5]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_111]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_111]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.5.jar:8.5.5]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_111]
【问题讨论】：
你是如何解决这个问题的？ 【参考方案1】：使用productname 代替key 和productamount 代替value。希望它能解决您的问题。
<tr th:each="entry : $entries" >
<td th:text="$entry.ProductName">H</td>
<td th:text="$entry.ProductAmount">A</td>
</tr>
【讨论】：
它只适用于productname 和productamount。但后来我得到一个只有“0”的表。【参考方案2】：
您的Stock 对象是private，因此只有您的ApplicationInitalizer 可以看到它。
private Stock products;
此外，由于您的代码并不清楚，您的 products 引用可能是 Stock 对象，而不是 HashMap，因此您无法对其进行迭代。
您可以为您的 Stock 对象提供一个getter 方法，并记住确保将stock.getEntries() 传递给您的Thymeleaf 模板。
【讨论】：
【参考方案3】：错误在model.addAttribute("entries", products);，
应该是model.addAttribute("entries", products.getEntries);。
而已。
【讨论】：
以上是关于遍历 Hashmap [Springboot、MVC、Java、Thymeleaf]的主要内容，如果未能解决你的问题，请参考以下文章