使用Java驱动程序将带有JsonNode字段的POJO插入MongoDB [英] Inserting a POJO with a JsonNode field into MongoDB using Java driver
问题描述
我正在使用Mongo Java驱动程序3.7
Im using Mongo Java driver 3.7
这是我的POJO(带有getter和setter) -
This is my POJO(with getters and setters) -
public class Sample{
public int field1;
public JsonNode field2;
}
我使用下面的代码将Sample的对象插入MongoDB。
Im using the below code to insert an object of Sample into MongoDB.
MongoCollection<Sample> myCollection = database.getCollection("myCollection",Sample.class);
ObjectMapper mapper = new ObjectMapper();
Sample obj = new Sample();
obj.setField1(1);
String sampleJSON = "{ \"key\": \"value\" }";
obj.setField2(mapper.readTree(sample));
myCollection.insertOne(obj);
看到输出:( JsonNode字段为空)
{
"_id" : ObjectId("5afbff8a8f621e1e328a8c4e"),
"field1" : 1
"field2" : [
[ ]
],
}
注意:
在调试模式下,很明显JsonNode是使用适当的数据创建的。但插入行为是行为不端。
我想我在这里错过了一些东西。任何潜在客户都赞赏。
Note: In debug mode, it is clear that the JsonNode is created with proper data. But insert is misbehaving. I guess I'm missing something here. Any leads appreciated.
更新:
我尝试为JsonNode类编写自定义编解码器,但它永远不会被mongo使用。这是我的编解码器代码 -
Update: I tried writing a custom codec for JsonNode class, but it is never being used by mongo. This is my codec code -
@Slf4j
public class JsonNodeCodec implements CollectibleCodec<JsonNode> {
@Inject
private ObjectMapper objectMapper;
@Override
public JsonNode generateIdIfAbsentFromDocument(JsonNode jsonNode) {
return null;
}
@Override
public boolean documentHasId(JsonNode jsonNode) {
return false;
}
@Override
public BsonValue getDocumentId(JsonNode jsonNode) {
return null;
}
@Override
public JsonNode decode(BsonReader reader, DecoderContext decoderContext) {
String task = reader.readString();
JsonNode node = objectMapper.readTree(task);
return node;
}
@Override
public void encode(BsonWriter writer, JsonNode jsonNode, EncoderContext encoderContext) {
writer.writeString(jsonNode.toString());
}
@Override
public Class<JsonNode> getEncoderClass() {
return JsonNode.class;
}
}
我正在注册这样的编解码器 -
And I'm registering the codec like this -
Codec<JsonNode> jsonNodeCodec = new JsonNodeCodec();
CodecRegistry codecRegistry = CodecRegistries.fromRegistries(com.mongodb.MongoClient.getDefaultCodecRegistry(),
CodecRegistries.fromCodecs(jsonNodeCodec),
CodecRegistries.fromProviders(PojoCodecProvider.builder().automatic(true).build())
);
PS:为自定义POJO注册的其他编解码器工作正常。但是这个编解码器永远不会用于编码/解码JSON对象
PS: Other codecs registered for custom POJOs are working fine. But this codec is never being used to encode/decode JSON objects
推荐答案
我在这里遇到了同样的问题并使用ObjectMapper解决了。
I was facing the same issue here and resolved using ObjectMapper.
使用以下:
ObjectMapper mapper = new ObjectMapper();
Map inputMap = mapper.convertValue(jsonNode, Map.class);
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