我需要在springboot中使用thymeleaf将map中的值解析为html模板。
这是我的控制器：

public class GraphController {

    @GetMapping("/displayBarGraph")
    public String barGraph(Model model) {
        Map<String, Integer> surveyMap = new LinkedHashMap<>();
        surveyMap.put("Java", 40);
        surveyMap.put("Dev oops", 25);
        surveyMap.put("Python", 20);
        surveyMap.put(".Net", 15);
        model.addAttribute("surveyMap", surveyMap);
         return "barGraph";
    }
}

这是我的模板：

我正在尝试使用控制器中的hashmapMap静态数据 surveyMap.key() 及 surveyMap.value() .
但在运行应用程序时，我遇到了以下错误：

Caused by: org.thymeleaf.exceptions.TemplateProcessingException: Could not parse as expression: "$,{surveyMap.key()}" (template: "barGraph" - line 40, col 27)
    at org.thymeleaf.standard.expression.StandardExpressionParser.parseExpression(StandardExpressionParser.java:131) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.standard.expression.StandardExpressionParser.parseExpression(StandardExpressionParser.java:62) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.standard.expression.StandardExpressionParser.parseExpression(StandardExpressionParser.java:44) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.engine.EngineEventUtils.parseAttributeExpression(EngineEventUtils.java:220) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.engine.EngineEventUtils.computeAttributeExpression(EngineEventUtils.java:207) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.standard.processor.AbstractStandardExpressionAttributeTagProcessor.doProcess(AbstractStandardExpressionAttributeTagProcessor.java:125) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.processor.element.AbstractAttributeTagProcessor.doProcess(AbstractAttributeTagProcessor.java:74) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.processor.element.AbstractElementTagProcessor.process(AbstractElementTagProcessor.java:95) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.util.ProcessorConfigurationUtils$ElementTagProcessorWrapper.process(ProcessorConfigurationUtils.java:633) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.engine.ProcessorTemplateHandler.handleOpenElement(ProcessorTemplateHandler.java:1314) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.engine.OpenElementTag.beHandled(OpenElementTag.java:205) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.engine.TemplateModel.process(TemplateModel.java:136) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.engine.TemplateManager.process(TemplateManager.java:519) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.util.LazyProcessingCharSequence.writeUnresolved(LazyProcessingCharSequence.java:85) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.util.AbstractLazyCharSequence.write(AbstractLazyCharSequence.java:103) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]
    at org.thymeleaf.engine.AbstractTextualTemplateEvent.writeContent(AbstractTextualTemplateEvent.java:224) ~[thymeleaf-3.0.12.RELEASE.jar:3.0.12.RELEASE]

有什么解决办法吗？