blocks|key|2995507|text|这是你的内部类的问题。Pojo类是测试类的non-static+inner+class，Jackson不能实例化该类。所以它可以序列化，但不能反序列化。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2995508|重新定义您的类，如下所示：|2995509|public+static+class+Pojo+{
++++public+String+foo;

++++@JsonRawValue
++++public+String+bar;
}|code-block|syntax|javascript|2995510|请注意添加了static|2995511|entityMap|0|LINK|mutability|MUTABLE|url|http://download.oracle.com/javase/tutorial/java/javaOO/nested.html^0|B|4|L|M|0|0|0|0|6|6|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@$9|Z|A|10|1|11]]|E|$]]|$1|F|3|G|5|6|7|12|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|13|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|14|8|@$9|15|A|16|B|C]]|D|@]|E|$]]|$1|O|3|-4|5|6|7|17|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]]]

This is a problem with your inner classes. The <code>Pojo</code> class is a <a href="http://download.oracle.com/javase/tutorial/java/javaOO/nested.html" rel="nofollow">non-static inner class</a> of your test class, and Jackson cannot instantiate that class. So it can serialize, but not deserialize.

Redefine your class like this:

<pre><code>public static class Pojo {
 public String foo;

 @JsonRawValue
 public String bar;
}
</code></pre>

Note the addition of <code>static</code>

blocks|key|3208841|text|@JsonRawValue仅用于序列化端，因为反向处理起来有点棘手。实际上，添加它是为了允许注入预编码的内容。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3208842|我猜有可能添加对反向的支持，尽管这将是相当尴尬的:内容将必须被解析，然后重写回“原始”形式，这可能是相同的，也可能不是相同的(因为字符引用可能不同)。这适用于一般情况。但也许它对某些子集的问题是有意义的。|3208843|但我认为对于您的特定情况，一个变通方法是将type指定为'java.lang.Object'，因为这应该可以正常工作:对于序列化，String将按原样输出，而对于反序列化，它将被反序列化为Map。实际上，如果是这样的话，您可能希望有单独的getter/setter；getter将为序列化返回String+(并且需要@JsonRawValue)；而setter将接受Map或Object。如果有意义，您可以将其重新编码为字符串。|3208844|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

@JsonRawValue is intended for serialization-side only, since the reverse direction is a bit trickier to handle. In effect it was added to allow injecting pre-encoded content.

I guess it would be possible to add support for reverse, although that would be quite awkward: content will have to be parsed, and then re-written back to "raw" form, which may or may not be the same (since character quoting may differ).
This for general case. But perhaps it would make sense for some subset of problems.

But I think a work-around for your specific case would be to specify type as 'java.lang.Object', since this should work ok: for serialization, String will be output as is, and for deserialization, it will be deserialized as a Map. Actually you might want to have separate getter/setter if so; getter would return String for serialization (and needs @JsonRawValue); and setter would take either Map or Object. You could re-encode it to a String if that makes sense.

blocks|key|3208846|text|在@StaxMan+answer之后，我做了以下工作，看起来很棒：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3208847|public+class+Pojo+{
++Object+json;

++@JsonRawValue
++public+String+getJson()+{
++++//+default+raw+value:+null+or+"[]"
++++return+json+==+null+?+null+:+json.toString();
++}

++public+void+setJson(JsonNode+node)+{
++++this.json+=+node;
++}
}|code-block|syntax|javascript|3208848|而且，为了忠实于最初的问题，这里是工作测试：|3208849|public+class+PojoTest+{
++ObjectMapper+mapper+=+new+ObjectMapper();

++@Test
++public+void+test()+throws+IOException+{
++++Pojo+pojo+=+new+Pojo("{\"foo\":18}");

++++String+output+=+mapper.writeValueAsString(pojo);
++++assertThat(output).isEqualTo("{\"json\":{\"foo\":18}}");

++++Pojo+deserialized+=+mapper.readValue(output,+Pojo.class);
++++assertThat(deserialized.json.toString()).isEqualTo("{\"foo\":18}");
++++//+deserialized.json+==+{"foo":18}
++}
}|3208850|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/users/59501/staxman^0|1|8|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]]]

Following <a href="https://stackoverflow.com/users/59501/staxman">@StaxMan</a> answer, I've made the following works like a charm:

<pre><code>public class Pojo {
 Object json;

 @JsonRawValue
 public String getJson() {
 // default raw value: null or "[]"
 return json == null ? null : json.toString();
 }

 public void setJson(JsonNode node) {
 this.json = node;
 }
}
</code></pre>

And, to be faithful to the initial question, here is the working test:

<pre><code>public class PojoTest {
 ObjectMapper mapper = new ObjectMapper();

 @Test
 public void test() throws IOException {
 Pojo pojo = new Pojo("{\"foo\":18}");

 String output = mapper.writeValueAsString(pojo);
 assertThat(output).isEqualTo("{\"json\":{\"foo\":18}}");

 Pojo deserialized = mapper.readValue(output, Pojo.class);
 assertThat(deserialized.json.toString()).isEqualTo("{\"foo\":18}");
 // deserialized.json == {"foo":18}
 }
}
</code></pre>

blocks|key|3208852|text|我也有同样的问题。我在这篇文章中找到了解决方案：Parse+JSON+tree+to+plain+class+using+Jackson+or+its+alternatives|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3208853|看看最后一个答案。通过为该属性定义一个自定义设置器，该属性接受JsonNode作为参数并调用jsonNode上的toString方法来设置String属性，就可以解决所有问题。|3208854|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/15659950/parse-json-tree-to-plain-class-using-jackson-or-its-alternatives^0|O|1S|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@$A|O|B|P|1|Q]]|C|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@]|C|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|C|$]]]|G|$H|$5|I|J|K|C|$L|M]]]]

I had the exact same issue.
I found the solution in this post :
<a href="https://stackoverflow.com/questions/15659950/parse-json-tree-to-plain-class-using-jackson-or-its-alternatives">Parse JSON tree to plain class using Jackson or its alternatives</a>

Check out the last answer.
By defining a custom setter for the property that takes a JsonNode as parameter and calls the toString method on the jsonNode to set the String property, it all works out.

blocks|key|286739|text|我可以使用一个自定义的反序列化程序(从here中剪切和粘贴)来做到这一点。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|286740|package+etc;

import+java.io.IOException;

import+com.fasterxml.jackson.core.JsonParser;
import+com.fasterxml.jackson.core.JsonProcessingException;
import+com.fasterxml.jackson.core.TreeNode;
import+com.fasterxml.jackson.databind.DeserializationContext;
import+com.fasterxml.jackson.databind.JsonDeserializer;

/**
+*+Keeps+json+value+as+json,+does+not+try+to+deserialize+it
+*+@author+roytruelove
+*
+*/
public+class+KeepAsJsonDeserialzier+extends+JsonDeserializer<String>+{

++++@Override
++++public+String+deserialize(JsonParser+jp,+DeserializationContext+ctxt)
++++++++++++throws+IOException,+JsonProcessingException+{

++++++++TreeNode+tree+=+jp.getCodec().readTree(jp);
++++++++return+tree.toString();
++++}
}|code-block|syntax|javascript|286741|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/24085052/295797^0|J|4|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

I was able to do this with a custom deserializer (cut and pasted from <a href="https://stackoverflow.com/a/24085052/295797">here</a>)

<pre class="lang-java prettyprint-override"><code>package etc;

import java.io.IOException;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.TreeNode;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;

/**
 * Keeps json value as json, does not try to deserialize it
 * @author roytruelove
 *
 */
public class KeepAsJsonDeserialzier extends JsonDeserializer&lt;String&gt; {

 @Override
 public String deserialize(JsonParser jp, DeserializationContext ctxt)
 throws IOException, JsonProcessingException {

 TreeNode tree = jp.getCodec().readTree(jp);
 return tree.toString();
 }
}
</code></pre>

blocks|key|286743|text|使用对象在两种情况下都可以很好地工作。此方法在两次反序列化原始值时会产生一些开销。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|286744|ObjectMapper+mapper+=+new+ObjectMapper();
RawJsonValue+value+=+new+RawJsonValue();
value.setRawValue(new+RawHello(){{this.data+=+"universe...";}});
String+json+=+mapper.writeValueAsString(value);
System.out.println(json);
RawJsonValue+result+=+mapper.readValue(json,+RawJsonValue.class);
json+=+mapper.writeValueAsString(result.getRawValue());
System.out.println(json);
RawHello+hello+=+mapper.readValue(json,+RawHello.class);
System.out.println(hello.data);|code-block|syntax|javascript|286745|RawHello.java|286746|public+class+RawHello+{

++++public+String+data;
}|286747|RawJsonValue.java|286748|public+class+RawJsonValue+{

++++private+Object+rawValue;

++++public+Object+getRawValue()+{
++++++++return+rawValue;
++++}

++++public+void+setRawValue(Object+value)+{
++++++++this.rawValue+=+value;
++++}
}|286749|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

Using an object works fine both ways... This method has a bit of overhead deserializing the raw value in two times.

<pre><code>ObjectMapper mapper = new ObjectMapper();
RawJsonValue value = new RawJsonValue();
value.setRawValue(new RawHello(){{this.data = "universe...";}});
String json = mapper.writeValueAsString(value);
System.out.println(json);
RawJsonValue result = mapper.readValue(json, RawJsonValue.class);
json = mapper.writeValueAsString(result.getRawValue());
System.out.println(json);
RawHello hello = mapper.readValue(json, RawHello.class);
System.out.println(hello.data);
</code></pre>

RawHello.java

<pre><code>public class RawHello {

 public String data;
}
</code></pre>

RawJsonValue.java

<pre><code>public class RawJsonValue {

 private Object rawValue;

 public Object getRawValue() {
 return rawValue;
 }

 public void setRawValue(Object value) {
 this.rawValue = value;
 }
}
</code></pre>

blocks|key|3208873|text|@JsonSetter可能会有所帮助。参见我的示例('data‘应该包含未解析的JSON)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3208874|class+Purchase
{
++++String+data;

++++@JsonProperty("signature")
++++String+signature;

++++@JsonSetter("data")
++++void+setData(JsonNode+data)
++++{
++++++++this.data+=+data.toString();
++++}
}|code-block|syntax|javascript|3208875|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

@JsonSetter may help. See my sample ('data' is supposed to contain unparsed JSON):

<pre><code>class Purchase
{
 String data;

 @JsonProperty("signature")
 String signature;

 @JsonSetter("data")
 void setData(JsonNode data)
 {
 this.data = data.toString();
 }
}
</code></pre>

blocks|key|280901|text|除了Roy+Truelove强大的answer之外，还介绍了如何根据@JsonRawValue的出现注入定制的反序列化器|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|280902|import+com.fasterxml.jackson.databind.Module;

@Component
public+class+ModuleImpl+extends+Module+{

++++@Override
++++public+void+setupModule(SetupContext+context)+{
++++++++context.addBeanDeserializerModifier(new+BeanDeserializerModifierImpl());
++++}
}|code-block|syntax|javascript|280903|280904|import+java.util.Iterator;

import+com.fasterxml.jackson.annotation.JsonRawValue;
import+com.fasterxml.jackson.databind.BeanDescription;
import+com.fasterxml.jackson.databind.DeserializationConfig;
import+com.fasterxml.jackson.databind.deser.BeanDeserializerBuilder;
import+com.fasterxml.jackson.databind.deser.BeanDeserializerModifier;
import+com.fasterxml.jackson.databind.deser.SettableBeanProperty;

public+class+BeanDeserializerModifierImpl+extends+BeanDeserializerModifier+{
++++@Override
++++public+BeanDeserializerBuilder+updateBuilder(DeserializationConfig+config,+BeanDescription+beanDesc,+BeanDeserializerBuilder+builder)+{
++++++++Iterator<SettableBeanProperty>+it+=+builder.getProperties();
++++++++while+(it.hasNext())+{
++++++++++++SettableBeanProperty+p+=+it.next();
++++++++++++if+(p.getAnnotation(JsonRawValue.class)+!=+null)+{
++++++++++++++++builder.addOrReplaceProperty(p.withValueDeserializer(KeepAsJsonDeserialzier.INSTANCE),+true);
++++++++++++}
++++++++}
++++++++return+builder;
++++}
}|280905|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/users/295797/roy-truelove|1|https://stackoverflow.com/a/24085100/800334^0|Y|D|2|C|0|H|6|1|0|0|0|0^^$0|@$1|2|3|4|5|6|7|X|8|@$9|Y|A|Z|B|C]]|D|@$9|10|A|11|1|12]|$9|13|A|14|1|15]]|E|$]]|$1|F|3|G|5|H|7|16|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|17|8|@]|D|@]|E|$]]|$1|L|3|M|5|H|7|18|8|@]|D|@]|E|$I|J]]|$1|N|3|-4|5|6|7|19|8|@]|D|@]|E|$]]]|O|$P|$5|Q|R|S|E|$T|U]]|V|$5|Q|R|S|E|$T|W]]]]

Adding to <a href="https://stackoverflow.com/users/295797/roy-truelove">Roy Truelove</a>'s great <a href="https://stackoverflow.com/a/24085100/800334">answer</a>, this is how to inject the custom deserialiser in response to appearance of <code>@JsonRawValue</code>:

<pre><code>import com.fasterxml.jackson.databind.Module;

@Component
public class ModuleImpl extends Module {

 @Override
 public void setupModule(SetupContext context) {
 context.addBeanDeserializerModifier(new BeanDeserializerModifierImpl());
 }
}
</code></pre>

<hr>

<pre><code>import java.util.Iterator;

import com.fasterxml.jackson.annotation.JsonRawValue;
import com.fasterxml.jackson.databind.BeanDescription;
import com.fasterxml.jackson.databind.DeserializationConfig;
import com.fasterxml.jackson.databind.deser.BeanDeserializerBuilder;
import com.fasterxml.jackson.databind.deser.BeanDeserializerModifier;
import com.fasterxml.jackson.databind.deser.SettableBeanProperty;

public class BeanDeserializerModifierImpl extends BeanDeserializerModifier {
 @Override
 public BeanDeserializerBuilder updateBuilder(DeserializationConfig config, BeanDescription beanDesc, BeanDeserializerBuilder builder) {
 Iterator&lt;SettableBeanProperty&gt; it = builder.getProperties();
 while (it.hasNext()) {
 SettableBeanProperty p = it.next();
 if (p.getAnnotation(JsonRawValue.class) != null) {
 builder.addOrReplaceProperty(p.withValueDeserializer(KeepAsJsonDeserialzier.INSTANCE), true);
 }
 }
 return builder;
 }
}
</code></pre>

blocks|key|286771|text|这个简单的解决方案对我很有效：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|286772|public+class+MyObject+{
++++private+Object+rawJsonValue;

++++public+Object+getRawJsonValue()+{
++++++++return+rawJsonValue;
++++}

++++public+void+setRawJsonValue(Object+rawJsonValue)+{
++++++++this.rawJsonValue+=+rawJsonValue;
++++}
}|code-block|syntax|javascript|286773|因此，我能够将JSON的原始值存储在rawJsonValue变量中，然后将它与其他字段一起反序列化(作为对象)回JSON，并通过我的REST发送。使用@JsonRawValue对我没有帮助，因为存储的JSON被反序列化为String，而不是object，这不是我想要的。|286774|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

This easy solution worked for me:

<pre><code>public class MyObject {
 private Object rawJsonValue;

 public Object getRawJsonValue() {
 return rawJsonValue;
 }

 public void setRawJsonValue(Object rawJsonValue) {
 this.rawJsonValue = rawJsonValue;
 }
}
</code></pre>

So I was able to store raw value of JSON in rawJsonValue variable and then it was no problem to deserialize it (as object) with other fields back to JSON and send via my REST. Using @JsonRawValue didnt helped me because stored JSON was deserialized as String, not as object, and that was not what I wanted.

blocks|key|2995610|text|这甚至适用于JPA实体：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2995611|private+String+json;

@JsonRawValue
public+String+getJson()+{
++++return+json;
}

public+void+setJson(final+String+json)+{
++++this.json+=+json;
}

@JsonProperty(value+=+"json")
public+void+setJsonRaw(JsonNode+jsonNode)+{
++++//+this+leads+to+non-standard+json,+see+discussion:+
++++//+setJson(jsonNode.toString());

++++StringWriter+stringWriter+=+new+StringWriter();
++++ObjectMapper+objectMapper+=+new+ObjectMapper();
++++JsonGenerator+generator+=+
++++++new+JsonFactory(objectMapper).createGenerator(stringWriter);
++++generator.writeTree(n);
++++setJson(stringWriter.toString());
}|code-block|syntax|javascript|2995612|理想情况下，ObjectMapper甚至JsonFactory都来自上下文，并且被配置为能够正确地处理您的JSON+(例如，标准的或带有非标准值的，如“无限”浮点数)。|2995613|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

This even works in a JPA entity:

<pre><code>private String json;

@JsonRawValue
public String getJson() {
 return json;
}

public void setJson(final String json) {
 this.json = json;
}

@JsonProperty(value = "json")
public void setJsonRaw(JsonNode jsonNode) {
 // this leads to non-standard json, see discussion: 
 // setJson(jsonNode.toString());

 StringWriter stringWriter = new StringWriter();
 ObjectMapper objectMapper = new ObjectMapper();
 JsonGenerator generator = 
 new JsonFactory(objectMapper).createGenerator(stringWriter);
 generator.writeTree(n);
 setJson(stringWriter.toString());
}
</code></pre>

Ideally the ObjectMapper and even JsonFactory are from the context and are configured so as to handle your JSON correctly (standard or with non-standard values like 'Infinity' floats for example).

blocks|key|3208939|text|下面是一个完整的工作示例，展示了如何使用Jackson模块使@JsonRawValue双向工作(序列化和反序列化)：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3208940|public+class+JsonRawValueDeserializerModule+extends+SimpleModule+{

++++public+JsonRawValueDeserializerModule()+{
++++++++setDeserializerModifier(new+JsonRawValueDeserializerModifier());
++++}

++++private+static+class+JsonRawValueDeserializerModifier+extends+BeanDeserializerModifier+{
++++++++@Override
++++++++public+BeanDeserializerBuilder+updateBuilder(DeserializationConfig+config,+BeanDescription+beanDesc,+BeanDeserializerBuilder+builder)+{
++++++++++++builder.getProperties().forEachRemaining(property+->+{
++++++++++++++++if+(property.getAnnotation(JsonRawValue.class)+!=+null)+{
++++++++++++++++++++builder.addOrReplaceProperty(property.withValueDeserializer(JsonRawValueDeserializer.INSTANCE),+true);
++++++++++++++++}
++++++++++++});
++++++++++++return+builder;
++++++++}
++++}

++++private+static+class+JsonRawValueDeserializer+extends+JsonDeserializer<String>+{
++++++++private+static+final+JsonDeserializer<String>+INSTANCE+=+new+JsonRawValueDeserializer();

++++++++@Override
++++++++public+String+deserialize(JsonParser+p,+DeserializationContext+ctxt)+throws+IOException,+JsonProcessingException+{
++++++++++++return+p.readValueAsTree().toString();
++++++++}
++++}
}|code-block|syntax|javascript|3208941|然后，您可以在创建ObjectMapper后注册模块|3208942|ObjectMapper+objectMapper+=+new+ObjectMapper();
objectMapper.registerModule(new+JsonRawValueDeserializerModule());

String+json+=+"{\"foo\":\"one\",\"bar\":{\"A\":false}}";
Pojo+deserialized+=+objectMapper.readValue(json,+Pojo.class);|3208943|entityMap^0|U|D|0|0|9|C|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|M|3|N|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|P|$]]

Here is a full working example of how to use Jackson modules to make <code>@JsonRawValue</code> work both ways (serialization and deserialization):

<pre><code>public class JsonRawValueDeserializerModule extends SimpleModule {

 public JsonRawValueDeserializerModule() {
 setDeserializerModifier(new JsonRawValueDeserializerModifier());
 }

 private static class JsonRawValueDeserializerModifier extends BeanDeserializerModifier {
 @Override
 public BeanDeserializerBuilder updateBuilder(DeserializationConfig config, BeanDescription beanDesc, BeanDeserializerBuilder builder) {
 builder.getProperties().forEachRemaining(property -&gt; {
 if (property.getAnnotation(JsonRawValue.class) != null) {
 builder.addOrReplaceProperty(property.withValueDeserializer(JsonRawValueDeserializer.INSTANCE), true);
 }
 });
 return builder;
 }
 }

 private static class JsonRawValueDeserializer extends JsonDeserializer&lt;String&gt; {
 private static final JsonDeserializer&lt;String&gt; INSTANCE = new JsonRawValueDeserializer();

 @Override
 public String deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
 return p.readValueAsTree().toString();
 }
 }
}
</code></pre>

Then you can register the module after creating the <code>ObjectMapper</code>:

<pre><code>ObjectMapper objectMapper = new ObjectMapper();
objectMapper.registerModule(new JsonRawValueDeserializerModule());

String json = "{\"foo\":\"one\",\"bar\":{\"A\":false}}";
Pojo deserialized = objectMapper.readValue(json, Pojo.class);
</code></pre>

blocks|key|280938|text|我也有类似的问题，但是我使用了一个包含很多JSON+itens+(List<String>)的列表。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|280939|public+class+Errors+{
++++private+Integer+status;
++++private+List<String>+jsons;
}|code-block|syntax|javascript|280940|我使用@JsonRawValue注释管理序列化。但是对于反序列化，我必须根据罗伊的建议创建一个自定义的反序列化器。|BOLD|280941|public+class+Errors+{

++++private+Integer+status;

++++@JsonRawValue
++++@JsonDeserialize(using+=+JsonListPassThroughDeserialzier.class)
++++private+List<String>+jsons;

}|280942|下面你可以看到我的“列表”反序列化器。|280943|public+class+JsonListPassThroughDeserializer+extends+JsonDeserializer<List<String>>+{

++++@Override
++++public+List<String>+deserialize(JsonParser+jp,+DeserializationContext+cxt)+throws+IOException,+JsonProcessingException+{
++++++++if+(jp.getCurrentToken()+==+JsonToken.START_ARRAY)+{
++++++++++++final+List<String>+list+=+new+ArrayList<>();
++++++++++++while+(jp.nextToken()+!=+JsonToken.END_ARRAY)+{
++++++++++++++++list.add(jp.getCodec().readTree(jp).toString());
++++++++++++}
++++++++++++return+list;
++++++++}
++++++++throw+cxt.instantiationException(List.class,+"Expected+Json+list");
++++}
}|280944|entityMap^0|X|C|0|0|3|D|1F|5|0|0|0|0^^$0|@$1|2|3|4|5|6|7|V|8|@$9|W|A|X|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|Z|8|@$9|10|A|11|B|C]|$9|12|A|13|B|M]]|D|@]|E|$]]|$1|N|3|O|5|H|7|14|8|@]|D|@]|E|$I|J]]|$1|P|3|Q|5|6|7|15|8|@]|D|@]|E|$]]|$1|R|3|S|5|H|7|16|8|@]|D|@]|E|$I|J]]|$1|T|3|-4|5|6|7|17|8|@]|D|@]|E|$]]]|U|$]]

I had a similar problem, but using a list with a lot of JSON itens (<code>List&lt;String&gt;</code>).

<pre><code>public class Errors {
 private Integer status;
 private List&lt;String&gt; jsons;
}
</code></pre>

I managed the serialization using the <code>@JsonRawValue</code> annotation. But for deserialization I had to create a custom deserializer based on Roy's suggestion.

<pre><code>public class Errors {

 private Integer status;

 @JsonRawValue
 @JsonDeserialize(using = JsonListPassThroughDeserialzier.class)
 private List&lt;String&gt; jsons;

}
</code></pre>

Below you can see my "List" deserializer.

<pre><code>public class JsonListPassThroughDeserializer extends JsonDeserializer&lt;List&lt;String&gt;&gt; {

 @Override
 public List&lt;String&gt; deserialize(JsonParser jp, DeserializationContext cxt) throws IOException, JsonProcessingException {
 if (jp.getCurrentToken() == JsonToken.START_ARRAY) {
 final List&lt;String&gt; list = new ArrayList&lt;&gt;();
 while (jp.nextToken() != JsonToken.END_ARRAY) {
 list.add(jp.getCodec().readTree(jp).toString());
 }
 return list;
 }
 throw cxt.instantiationException(List.class, "Expected Json list");
 }
}
</code></pre>

I am trying to include raw JSON inside a Java object when the object is (de)serialized using Jackson. In order to test this functionality, I wrote the following test:

<pre><code>public static class Pojo {
 public String foo;

 @JsonRawValue
 public String bar;
}

@Test
public void test() throws JsonGenerationException, JsonMappingException, IOException {

 String foo = "one";
 String bar = "{\"A\":false}";

 Pojo pojo = new Pojo();
 pojo.foo = foo;
 pojo.bar = bar;

 String json = "{\"foo\":\"" + foo + "\",\"bar\":" + bar + "}";

 ObjectMapper objectMapper = new ObjectMapper();
 String output = objectMapper.writeValueAsString(pojo);
 System.out.println(output);
 assertEquals(json, output);

 Pojo deserialized = objectMapper.readValue(output, Pojo.class);
 assertEquals(foo, deserialized.foo);
 assertEquals(bar, deserialized.bar);
}
</code></pre>

The code outputs the following line:

<pre><code>{"foo":"one","bar":{"A":false}}
</code></pre>

The JSON is exactly how I want things to look. Unfortunately, the code fails with an exception when attempting to read the JSON back in to the object. Here is the exception:

<blockquote>
 org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of java.lang.String out of START_OBJECT token
 at [Source: java.io.StringReader@d70d7a; line: 1, column: 13] (through reference chain: com.tnal.prism.cobalt.gather.testing.Pojo["bar"])
</blockquote>

Why does Jackson function just fine in one direction but fail when going the other direction? It seems like it should be able to take its own output as input again. I know what I'm trying to do is unorthodox (the general advice is to create an inner object for <code>bar</code> that has a property named <code>A</code>), but I don't want to interact with this JSON at all. My code is acting as a pass-through for this code -- I want to take in this JSON and send it back out again without touching a thing, because when the JSON changes I don't want my code to need modifications.

Thanks for the advice.

EDIT: Made Pojo a static class, which was causing a different error.

How can I include raw JSON in an object using Jackson?

JSON

Java

当使用Jackson对对象进行(反)序列化时，我尝试在Java对象中包含原始JSON。为了测试此功能，我编写了以下测试：public static class Pojo {    public String foo;    @JsonRawValue    public String bar;}@Testpublic ...

问如何使用Jackson在对象中包含原始JSON？
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