解决：cannot deserialize from Object value (no delegate- or property-based Creator)

解决：cannot deserialize from Object value (no delegate- or property-based Creator)

前因后果：
前两天在写一个简单页面的时候，前端通过ajax请求发送参数，后端创建了一个实体类用来接收参数，这个实体类添加了Lombok的@Data注解，没有创建其他构造函数，当前端发送请求时后端控制台就会抛出以下异常，后经过查询发现原来是因为实体类没有无参构造函数造成的。

解决方式：
手动创建一个无参构造器或者添加Lombok注解@NoArgsConstructor即可。

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.http.converter.HttpMessageConversionException: Type definition error: [simple type, class com.thunisoft.commons.cryptoonline.bean.ParamBean]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `com.thunisoft.commons.cryptoonline.bean.ParamBean` (no Creators, like default constructor, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
 at [Source: (PushbackInputStream); line: 1, column: 2]] with root cause

com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `com.thunisoft.commons.cryptoonline.bean.ParamBean` (no Creators, like default constructor, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
 at [Source: (PushbackInputStream); line: 1, column: 2]
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