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如何在ObjectMapper中忽略空对象“{}”而不是空字符串?

[英]How to ignore empty Objects “{}” but not empty Strings in ObjectMapper?

I need to serialize (ignoring empty objects ("{}")) non-structured object which can have any content. 我需要序列化(忽略空对象(“{}”))非结构化对象,它可以包含任何内容。

From version 2.9.X FasterXML have changed logic of it work for (Include.NON_EMPTY). 从版本2.9.X FasterXML改变了它的逻辑(Include.NON_EMPTY)。 In older version it had worked as I need. 在旧版本中它可以按我的需要工作。 But now it is ignoring empty strings too. 但现在它也忽略了空字符串。

ObjectMapper mapper = new ObjectMapper();
mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
mapper.setSerializationInclusion(JsonInclude.Include.NON_EMPTY);

Lets suppose that we have next java object (for convenience it will look like a JSON): 让我们假设我们有下一个java对象(为方便起见,它看起来像一个JSON):

{
    "mapA": {},
    "listA": ["",
        {
            "emptyString": "",
            "string": "some text"
        },
        {}
    ],
    "emptyString": "",
    "mapB": {
        "emptyString": "",
        "mapC": {}
    }
}

Converting it to JsonNode: 将其转换为JsonNode:

   mapper.convertValue(/*our Object*/, JsonNode.class);

Desired output(Again for convenience it will look like a JSON): 期望的输出(为方便起见,它看起来像JSON):

{
    "listA": ["",
        {
            "emptyString": "",
            "string": "some text"
        }
    ],
    "emptyString": "",
    "mapB": {
        "emptyString": ""
    }
}

I used Include.CUSTOM : 我使用了Include.CUSTOM

    private static class ExludeEmptyObjects{
        @Override
        public boolean equals(Object o) {
            if (o instanceof Map) {
                return ((Map) o).size() == 0;
            }
            if (o instanceof Collection) {
                return ((Collection) o).size() == 0;
            }
            return false;
        }
    }

   ObjectMapper mapper = new ObjectMapper();
   mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
   mapper.setDefaultPropertyInclusion(Value.construct(Include.NON_EMPTY, Include.CUSTOM, null, ExludeEmptyObjects.class));

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