如何从POJO中删除字段

Question

public class user {

    private String planId;

    private String eid;

    @JsonProperty(access = JsonProperty.Access.WRITE_ONLY)
    private Collection<String> userIds;

}

我有一个像上面一样的pojo

用于创建json请求对象的代码如下：

    public UserCollection getUserCollection(final user args) {
            Map<String, String> headersMap = new HashMap<>();
            ObjectMapper jacksonMapper = new ObjectMapper();
            jacksonMapper.disable(MapperFeature.USE_ANNOTATIONS); // this line is creating the userIds field to reflect
 //By any code we can remove the userId field from the args object
    
            String responseBody = null;
            String responseStatus = null;
                String jsonRequestBody = jacksonMapper.writeValueAsString(args);
    }

我只是想通过不删除任何上述代码从args中删除userIds。

提前谢谢。

Answer 1

我不知道如何在不删除注释处理代码的情况下解决这个问题，您可能应该添加一个自定义序列化程序。你可以在这里进一步了解这个话题。

public class HelloWorld {

    public static void main(String[] args) throws JsonProcessingException {
        User myItem = new User("planId", "eId", List.of("1", "2"));
        ObjectMapper mapper = new ObjectMapper();

        SimpleModule module = new SimpleModule();
        module.addSerializer(User.class, new UserSerializer());
        mapper.registerModule(module);

        String serialized = mapper.writeValueAsString(myItem);
    }

    @Data
    @AllArgsConstructor
    public static class User {

        private String planId;
        private String eId;
        private Collection<String> userIds;
    }

    public static class UserSerializer extends StdSerializer<User> {

        public UserSerializer() {
            this(null);
        }

        public UserSerializer(Class<User> t) {
            super(t);
        }

        @Override
        public void serialize(User value, JsonGenerator gen, SerializerProvider provider) throws IOException{

            gen.writeStartObject();
            gen.writeStringField("planId", value.planId);
            gen.writeStringField("eId", value.eId);
            gen.writeEndObject();
        }
    }
}

如果必须在没有注释的情况下使用它，并且无法添加自定义序列化程序，那么应该将用户类映射到没有相关字段的更具体的类中，然后序列化该类。