JSON deserialization with malformed JSON

On a REST api i receive a Json that gets mapped to a Java Object:

@RequestMapping(value = "/example", method = RequestMethod.POST)
    public @ResponseBody
    ReturnObject doReturn(@RequestBody ProblemObject requestBody)

The object is simple:

public class ProblemObject implements Serializable {

    private String field1;
    private String field2;

   //This appears to create problems, removing this Jackson throws exception correctly!!
   public ProblemObject(String field2) {
       this.field2 = field2;
   }

   public ProblemObject(String field1, String field2) {
       this.field1 = field1;
       this.field2 = field2;
   }
}

The problem is Jackson tries to deserialize a malformed JSON, with not so good results:

 "field1": "test",
 "field2": "test"
}

notice no opening brace. This causes the object to get mapped with field1 having a value of “field1” and field2 being null. Doing any other changes throws correctly an exception ( removing comma, removing close brace, ecc ). The only problem is with the opening brace. Jackson version 2.8.1

Example project: jackson_json_mapping.zip JSON to send:

"field1": "test",
 "field2": "test2"
}

[cowtowncoder]

@beeva-juanmanuelperez That is different and by design: only enough content is read to tokenize a full value. There is another RFE to add support for consuming whole input, and in that case exception would be thrown. Until then if you do want to verify if there’s trailing content you need to construct JsonParser separately, pass it to readValue(), and then manually advance parser and verify that nextToken() returns null – if not (or throws parse exception), you can indicate error.

[cowtowncoder]

Created #1583 to cover improvement idea since I was unable to locate existing issue.