springBoot2提示HttpMessageNotWritableException: No converter found for return value of type

在controller返回string是可以在頁面顯示出來的，但是返回map，object則報一下錯誤：

HttpMessageNotWritableException: No converter found for return value of type

解決辦法：

在springboot的pom.xml文件中添加下面依賴

 <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
    <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
      <version>2.9.1</version>
    </dependency>

參考文章：https://blog.csdn.net/sinat_34104446/article/details/82771341