com.fasterxml.jackson.databind.JsonMappingException: Can not construct instance of entity.XwjUser: no suitable constructor found, can not deserialize from Object value (missing default constructor or creator, or perhaps need to add/enable type information?)

 at [Source: {"id":,"message":"Hello World","sendTime":,"intList":null}; line: , column: ]

    at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:)

    at com.fasterxml.jackson.databind.DeserializationContext.instantiationException(DeserializationContext.java:)

    at com.fasterxml.jackson.databind.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:)

    at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromObjectUsingNonDefault(BeanDeserializerBase.java:)

    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:)

    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:)

    at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:)

    at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:)

    at testJson.TestObjectMapper.testObj(TestObjectMapper.java:)

    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)


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