java - 将java转换为Json时是否可以忽略内部类名和变量

Question

我正在尝试创建一个 json，其中外部类对象具有所有内部类的字段，但我不希望 json 中包含内部类的对象。

我试过这个:

public class College {
    Student student;

    class Student {
        int id;
        String name;
    }
}

实际结果:

{
  "college" {
      "student" {
          "id" : "",
          "name" : ""
      }
  }
}

期望:

{
  "college" {
      "id" : "",
      "name" : ""
  }
}

Answer 1

嗯，它看起来不像是正确的 json。如果您使用的是 jackson 库，请使用 @JsonUnwrapped 注释

如果您想要的结果与您预期的类似...如下所示:

大学类(class):

class College {
    @JsonUnwrapped
    Student student;

    public Student getStudent() {
        return student;
    }

    public void setStudent(Student student) {
        this.student = student;
    }
}

学生类(class):

class Student {
    String id;
    String name;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

测试代码:

class JacksonTest {
    @Test
    public void objToJsonTest() {
        Student student = new Student();
        College college = new College();
        college.setStudent(student);

        ObjectMapper mapper = new ObjectMapper();
        mapper.enable(SerializationFeature.WRAP_ROOT_VALUE);

        String s = null;
        try {
            s = mapper.writeValueAsString(college);
        } catch (Exception e) {
            // handle exception
        }
        // print json format string
        System.out.println(s);
    }
}

结果:

{"College":{"id":"","name":""}}

没有@JsonUnwrapped注解:

{"College":{"student":{"id":"","name":""}}}