Jackson-annotations-jsoninclude

Jackson Annotations-@JsonInclude

*@ JsonInclude* は、null/空またはデフォルト値を持つ除外プロパティで使用されます。

例-@JsonInclude

import java.io.IOException;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonTester {
   public static void main(String args[]){
      ObjectMapper mapper = new ObjectMapper();
      try {
         Student student = new Student(1,null);
         String jsonString = mapper
            .writerWithDefaultPrettyPrinter()
            .writeValueAsString(student);
         System.out.println(jsonString);
      }
      catch (IOException e) {
         e.printStackTrace();
      }
   }
}
@JsonInclude(JsonInclude.Include.NON_NULL)
class Student {
   public int id;
   public String name;

   Student(int id,String name){
      this.id = id;
      this.name = name;
   }
}

出力

{
   "id" : 1
}