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PONullPointerException during JSON Deserializtion in Spring
 

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  1. PONullPointerException during JSON Deserializtion in Spring
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    <p>I have a Space object for which I have written a custom serializer and deserializer. Now I have wrapped this object in a simple object for some context. What I would like to do is serialize/deserialize this wrapper.</p> <p>My Space object serializes/deserializes fine. I just get the following exception when attempting to deserialize:</p> <pre><code>java.lang.NullPointerException at org.codehaus.jackson.impl.ReaderBasedParser._skipWSOrEnd(ReaderBasedParser.java:1477) at org.codehaus.jackson.impl.ReaderBasedParser.nextToken(ReaderBasedParser.java:368) at org.codehaus.jackson.map.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:690) at org.codehaus.jackson.map.deser.BeanDeserializer.deserialize(BeanDeserializer.java:580) at org.codehaus.jackson.map.ObjectMapper._readMapAndClose(ObjectMapper.java:2732) at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1863) at com.newoak.noc.curve.model.tests.ModelParamsTest.deserializeGraph(ModelParamsTest.java:100) at com.newoak.noc.curve.model.tests.ModelParamsTest.testSerializationDeserialization(ModelParamsTest.java:113) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:601) </code></pre> <p>Here is where my exception is thrown:</p> <pre><code>public ModelParamGraph deserializeGraph(String json) throws JsonGenerationException, JsonMappingException, IOException { ObjectMapper mapper = new ObjectMapper(); SimpleModule testModule = new SimpleModule("MyModule", new Version(1, 0, 0, null)); testModule.addSerializer(new SpaceJsonSerializer()); testModule.addDeserializer(Space.class, new SpaceJsonDeserializer()); mapper.registerModule(testModule); ModelParamGraph space = mapper.readValue(json, ModelParamGraph.class); return space; } </code></pre> <p>This is my wrapper:</p> <pre><code>public class ModelParamGraph implements Serializable { private static final long serialVersionUID = 6123736933251596579L; @JsonSerialize(using=SpaceJsonSerializer.class) @JsonDeserialize(using=SpaceJsonDeserializer.class) public Space&lt;TModelParam&gt; paramSpace; public String source; public Date date; private static Log log_ = LogFactory.getLog(ModelParamGraph.class); public ModelParamGraph(){} public ModelParamGraph(String source, Date date) { setSource(source); setDate(date); log_.debug("Creating ModelParam Graph"); setParamSpace(new Space&lt;TModelParam&gt;()); } public Space&lt;TModelParam&gt; getParamSpace() { return paramSpace; } public void setParamSpace(Space&lt;TModelParam&gt; paramSpace) { this.paramSpace = paramSpace; } public void addParameter(TModelParam param, TModelParam parent) { if (paramSpace.getRootData() == null) { paramSpace.addData(param, true); } else { paramSpace.addData(param); } if (parent != null) { paramSpace.link(parent, param, "parent"); } } public String getSource() { return source; } public void setSource(String source) { this.source = source; } public Date getDate() { return date; } public void setDate(Date date) { this.date = date; } </code></pre> <p>}</p> <p>Any help would be greatly appreciated! Thanks!</p>
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    1. USbjoern
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    1. This table or related slice is empty.
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    1. COIs `json` possibly `null`?
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      1. PONullPointerException during JSON Deserializtion in Spring
      1. USSotirios Delimanolis
    2. COno, json is properly formatted json from a prior serialization
      singulars
      1. PONullPointerException during JSON Deserializtion in Spring
      1. USbjoern
    3. COOk, let's try to reproduce. Post the value of `json`, your `SpaceJsonSerializer` and `SpaceJsonDeserializer`.
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      1. PONullPointerException during JSON Deserializtion in Spring
      1. USSotirios Delimanolis
 

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