Jackson databind JSON boolean conversion

Question

I'm using Jackson objectMapper to convert a JSON to an object and do some transformations and converting it back to JSON.

The JSON is like { "id":"abc1243", "val":1, "isDel":true}

In the above val is int and isDel is boolean.

My object is defined as below

public class MyObj{
  private String id;
  private String val;
  private String isDel;
   //getters and setters

}

When I convert the JSON to the MyObj, the String id and Int val are bound into the String but the boolean is not binded and hence I get null.

Im using the below approach

   ObjectMapper mapper = new ObjectMapper();
    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
    mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
    try {
        MyObj myObj = mapper.readValue(new File("/Users/sample.json"), MyObj.class);
}

May I know why the boolean is not binded to the String member.

Answer 1

You can have a setter that accepts boolean and does the necessary conversion

@JsonProperty("isDel")
public void setIsDel(boolean isDel) {
  this.isDel = String.valueOf(isDel);
}

note: this does not interfere with a setter that accepts String (the annotation tells Jackson to use this particular method)