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jackson JsonDeserializer stackoverflow

I am trying to extract attributes from a json sting in Java and I am writing a JsonDeseriizer to do it.
My attempt is shown below:

public class testJacksonSimple {
@JsonDeserialize(using = ItemDeserializerJson.class)
public static class Item {
public int id;
public String itemName;

public Item(){};
public Item(int id, String itemName) {
this.id = id;
this.itemName = itemName;
}

public void setId(int id) {
this.id = id;
}

public int getId() {
return id;
}
}

public static class ItemDeserializerJson extends JsonDeserializer<Item> {

ObjectReader reader = new ObjectMapper().reader();

@Override
public Item deserialize(JsonParser jp, DeserializationContext context) throws IOException {
if(jp.currentToken() != JsonToken.VALUE_NULL) {
return reader.readValue(jp, Item.class);
} else {
return null;
}
}
}
}


This is my test case:

public class test {
public static void main(String args){
ObjectMapper mapper = new ObjectMapper();
String json = "{n" +
" "id": 1,n" +
" "itemName": "theItem"n" +
"}";
System.out.println(json);
testJacksonSimple.Item itemWithOwner = null;
try {
itemWithOwner = new ObjectMapper().readValue(json, testJacksonSimple.Item.class);
} catch (Exception e) {
e.printStackTrace();
}
System.out.println(itemWithOwner.id);
System.out.println(itemWithOwner.itemName);
}
}


I got the error:

Exception in thread "main" java.lang.StackOverflowError
at java.lang.reflect.Method.getParameterTypes(Method.java:264)
at sun.reflect.annotation.AnnotationInvocationHandler.invoke(AnnotationInvocationHandler.java:59)
at com.sun.proxy.$Proxy2.annotationType(Unknown Source)
at com.fasterxml.jackson.databind.introspect.AnnotationMap._add(AnnotationMap.java:135)
at com.fasterxml.jackson.databind.introspect.AnnotationMap.addIfNotPresent(AnnotationMap.java:101)
at com.fasterxml.jackson.databind.introspect.AnnotatedClass._addAnnotationsIfNotPresent(AnnotatedClass.java:1061)
at com.fasterxml.jackson.databind.introspect.AnnotatedClass._resolveClassAnnotations(AnnotatedClass.java:399)
at com.fasterxml.jackson.databind.introspect.AnnotatedClass._classAnnotations(AnnotatedClass.java:376)
at com.fasterxml.jackson.databind.introspect.AnnotatedClass.getAnnotation(AnnotatedClass.java:248)
at com.fasterxml.jackson.databind.AnnotationIntrospector._findAnnotation(AnnotationIntrospector.java:1436)
at com.fasterxml.jackson.databind.introspect.JacksonAnnotationIntrospector.findAutoDetectVisibility(JacksonAnnotationIntrospector.java:349)
at com.fasterxml.jackson.databind.introspect.POJOPropertiesCollector.<init>(POJOPropertiesCollector.java:129)


Just do not understand why I got error stackoverflow. I can get correct result without using custom JSONDeserializer, but I want to test it. Any help is appreciated.

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