Jackson 2.18.2 · com.fasterxml.jackson.databind.deser.impl.ErrorThrowingDeserializer

public Class ErrorThrowingDeserializer

A deserializer that stores an Error caught during constructing of the deserializer, which needs to be deferred and only during actual attempt to deserialize a value of given type. Note that null and empty values can be deserialized without error.

Since

2.9 Note: prior to this version was named NoClassDefFoundDeserializer

Field Summary

Modifier and Type	Field and Description
private final Error	_cause

Constructor Summary

Access	Constructor and Description
public	ErrorThrowingDeserializer(NoClassDefFoundError cause)

Modifier and Type	Method and Description
public Object	deserialize(JsonParser Parser used for reading JSON content jp, DeserializationContext Context that can be used to access information about this deserialization activity. ctxt) Implements abstract com.fasterxml.jackson.databind.JsonDeserializer.deserialize. Method that can be called to ask implementation to deserialize JSON content into the value type this serializer handles.

Modifier and Type

Method and Description

public Object

deserialize(JsonParser

Parser used for reading JSON content

jp, DeserializationContext

Context that can be used to access information about this deserialization activity.

ctxt)

Implements abstract com.fasterxml.jackson.databind.JsonDeserializer.deserialize.

Method that can be called to ask implementation to deserialize JSON content into the value type this serializer handles.

Field Detail

_cause	back to summary
private final Error _cause

Constructor Detail

ErrorThrowingDeserializer	back to summary
public ErrorThrowingDeserializer(NoClassDefFoundError cause)

Method Detail

deserialize back to summary

deserialize	back to summary
public Object deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException Implements abstract com.fasterxml.jackson.databind.JsonDeserializer.deserialize. Doc from com.fasterxml.jackson.databind.JsonDeserializer.deserialize. Method that can be called to ask implementation to deserialize JSON content into the value type this serializer handles. Returned instance is to be constructed by method itself. Pre-condition for this method is that the parser points to the first event that is part of value to deserializer (and which is never JSON 'null' literal, more on this below): for simple types it may be the only value; and for structured types the Object start marker or a FIELD_NAME. The two possible input conditions for structured types result from polymorphism via fields. In the ordinary case, Jackson calls this method when it has encountered an OBJECT_START, and the method implementation must advance to the next token to see the first field name. If the application configures polymorphism via a field, then the object looks like the following. { "@class": "class name", ... } Jackson consumes the two tokens (the `@class` field name and its value) in order to learn the class and select the deserializer. Thus, the stream is pointing to the FIELD_NAME for the first field after the @class. Thus, if you want your method to work correctly both with and without polymorphism, you must begin your method with: if (p.currentToken() == JsonToken.START_OBJECT) { p.nextToken(); } This results in the stream pointing to the field name, so that the two conditions align. Post-condition is that the parser will point to the last event that is part of deserialized value (or in case deserialization fails, event that was not recognized or usable, which may be the same event as the one it pointed to upon call). Handling null values (JsonToken.VALUE_NULL) : Note that this method is never called for the JSON `null` literal to avoid every deserializer from having to handle null values. Instead, the `JsonDeserializer#getNullValue(DeserializationContext)` method is called to produce a null value. To influence null handling, custom deserializers should override `JsonDeserializer#getNullValue(DeserializationContext)` and usually also `JsonDeserializer#getNullAccessPattern()`. Parameters jp:JsonParser Parser used for reading JSON content ctxt:DeserializationContext Context that can be used to access information about this deserialization activity. Returns:Object Deserialized value Annotations @Override

public Object deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException

Implements abstract com.fasterxml.jackson.databind.JsonDeserializer.deserialize.

Doc from com.fasterxml.jackson.databind.JsonDeserializer.deserialize.

Method that can be called to ask implementation to deserialize JSON content into the value type this serializer handles. Returned instance is to be constructed by method itself.

Pre-condition for this method is that the parser points to the first event that is part of value to deserializer (and which is never JSON 'null' literal, more on this below): for simple types it may be the only value; and for structured types the Object start marker or a FIELD_NAME.

The two possible input conditions for structured types result from polymorphism via fields. In the ordinary case, Jackson calls this method when it has encountered an OBJECT_START, and the method implementation must advance to the next token to see the first field name. If the application configures polymorphism via a field, then the object looks like the following.

      {
          "@class": "class name",
          ...
      }

Jackson consumes the two tokens (the @class field name and its value) in order to learn the class and select the deserializer. Thus, the stream is pointing to the FIELD_NAME for the first field after the @class. Thus, if you want your method to work correctly both with and without polymorphism, you must begin your method with:

       if (p.currentToken() == JsonToken.START_OBJECT) {
         p.nextToken();
       }

This results in the stream pointing to the field name, so that the two conditions align.

Post-condition is that the parser will point to the last event that is part of deserialized value (or in case deserialization fails, event that was not recognized or usable, which may be the same event as the one it pointed to upon call).

Handling null values (JsonToken.VALUE_NULL)
: Note that this method is never called for the JSON null literal to avoid every deserializer from having to handle null values. Instead, the JsonDeserializer#getNullValue(DeserializationContext) method is called to produce a null value. To influence null handling, custom deserializers should override JsonDeserializer#getNullValue(DeserializationContext) and usually also JsonDeserializer#getNullAccessPattern().

Parameters

jp:JsonParser: Parser used for reading JSON content
ctxt:DeserializationContext: Context that can be used to access information about this deserialization activity.

Returns:Object

Deserialized value

Annotations