| public StackTraceElement deserialize(JsonParser p, 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
- p:JsonParser
Parser used for reading JSON content
- ctxt:DeserializationContext
Context that can be used to access information about
this deserialization activity.
- Returns:StackTraceElement
Deserialized value
- Annotations
- @Override
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