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java jackson 自定义_java – 如何在自定义反序列化器中使用jackson ObjectMapper?

我尝试编写自定义jackson反序列化器.我希望“查看”一个字段并对类执行自动反序列化,请参阅下面的示例:

import com.fasterxml.jackson.core.JsonParser;

import com.fasterxml.jackson.core.JsonProcessingException;

import com.fasterxml.jackson.core.ObjectCodec;

import com.fasterxml.jackson.databind.DeserializationContext;

import com.fasterxml.jackson.databind.JsonDeserializer;

import com.fasterxml.jackson.databind.JsonNode;

import com.mypackage.MyInterface;

import com.mypackage.MyFailure;

import com.mypackage.MySuccess;

import java.io.IOException;

public class MyDeserializer extends JsonDeserializer {

@Override

public MyInterface deserialize(JsonParser jp, DeserializationContext ctxt)

throws IOException, JsonProcessingException {

ObjectCodec codec = jp.getCodec();

JsonNode node = codec.readTree(jp);

if (node.has("custom_field")) {

return codec.treeToValue(node, MyFailure.class);

} else {

return codec.treeToValue(node, MySuccess.class);

}

}

}

的POJO:

public class MyFailure implements MyInterface {}

public class MySuccess implements MyInterface {}

@JsonDeserialize(using = MyDeserializer.class)

public interface MyInterface {}

我得到了StackOverflowError.理解codec.treeToValue调用相同的反序列化器.有没有办法在custom deseralizer中使用codec.treeToValue或ObjectMapper.readValue(String,Class< T>)?