package com.fasterxml.jackson.databind.ser.std;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Type;
import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.annotation.JacksonStdImpl;
import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitable;
import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrapper;
import com.fasterxml.jackson.databind.jsonschema.SchemaAware;
import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
import com.fasterxml.jackson.databind.jsontype.TypeSerializerWrapper;
import com.fasterxml.jackson.databind.ser.BeanSerializer;
import com.fasterxml.jackson.databind.ser.ContextualSerializer;
/**
* Serializer class that can serialize Object that have a
* {@link com.fasterxml.jackson.annotation.JsonValue} annotation to
* indicate that serialization should be done by calling the method
* annotated, and serializing result it returns.
* <p/>
* Implementation note: we will post-process resulting serializer
* (much like what is done with {@link BeanSerializer})
* to figure out actual serializers for final types.
* This must be done from {@link #createContextual} method, and NOT from constructor;
* otherwise we could end up with an infinite loop.
*/
@JacksonStdImpl
public class JsonValueSerializer
extends StdSerializer<Object>
implements ContextualSerializer, JsonFormatVisitable, SchemaAware
{
protected final Method _accessorMethod;
protected final JsonSerializer<Object> _valueSerializer;
protected final BeanProperty _property;
/**
* This is a flag that is set in rare (?) cases where this serializer
* is used for "natural" types (boolean, int, String, double); and where
* we actually must force type information wrapping, even though
* one would not normally be added.
*/
protected final boolean _forceTypeInformation;
/*
/**********************************************************
/* Life-cycle
/**********************************************************
*/
/**
* @param ser Explicit serializer to use, if caller knows it (which
* occurs if and only if the "value method" was annotated with
* {@link com.fasterxml.jackson.databind.annotation.JsonSerialize#using}), otherwise
* null
*/
public JsonValueSerializer(Method valueMethod, JsonSerializer<Object> ser)
{
super(Object.class);
_accessorMethod = valueMethod;
_valueSerializer = ser;
_property = null;
_forceTypeInformation = true; // gets reconsidered when we are contextualized
}
@SuppressWarnings("unchecked")
public JsonValueSerializer(JsonValueSerializer src, BeanProperty property,
JsonSerializer<?> ser, boolean forceTypeInfo)
{
super(_notNullClass(src.handledType()));
_accessorMethod = src._accessorMethod;
_valueSerializer = (JsonSerializer<Object>) ser;
_property = property;
_forceTypeInformation = forceTypeInfo;
}
@SuppressWarnings("unchecked")
private final static Class<Object> _notNullClass(Class<?> cls) {
return (cls == null) ? Object.class : (Class<Object>) cls;
}
public JsonValueSerializer withResolved(BeanProperty property,
JsonSerializer<?> ser, boolean forceTypeInfo)
{
if (_property == property && _valueSerializer == ser
&& forceTypeInfo == _forceTypeInformation) {
return this;
}
return new JsonValueSerializer(this, property, ser, forceTypeInfo);
}
/*
/**********************************************************
/* Post-processing
/**********************************************************
*/
/**
* We can try to find the actual serializer for value, if we can
* statically figure out what the result type must be.
*/
// @Override
public JsonSerializer<?> createContextual(SerializerProvider provider,
BeanProperty property)
throws JsonMappingException
{
JsonSerializer<?> ser = _valueSerializer;
if (ser == null) {
/* Can only assign serializer statically if the declared type is final:
* if not, we don't really know the actual type until we get the instance.
*/
// 10-Mar-2010, tatu: Except if static typing is to be used
if (provider.isEnabled(MapperFeature.USE_STATIC_TYPING)
|| Modifier.isFinal(_accessorMethod.getReturnType().getModifiers())) {
JavaType t = provider.constructType(_accessorMethod.getGenericReturnType());
// false -> no need to cache
/* 10-Mar-2010, tatu: Ideally we would actually separate out type
* serializer from value serializer; but, alas, there's no access
* to serializer factory at this point...
*/
/* 09-Dec-2010, tatu: Turns out we must add special handling for
* cases where "native" (aka "natural") type is being serialized,
* using standard serializer
*/
ser = provider.findTypedValueSerializer(t, false, _property);
boolean forceTypeInformation = isNaturalTypeWithStdHandling(t.getRawClass(), ser);
return withResolved(property, ser, forceTypeInformation);
}
} else if (ser instanceof ContextualSerializer) {
ser = ((ContextualSerializer) ser).createContextual(provider, property);
return withResolved(property, ser, _forceTypeInformation);
}
return this;
}
/*
/**********************************************************
/* Actual serialization
/**********************************************************
*/
@Override
public void serialize(Object bean, JsonGenerator jgen, SerializerProvider prov)
throws IOException, JsonGenerationException
{
try {
Object value = _accessorMethod.invoke(bean);
if (value == null) {
prov.defaultSerializeNull(jgen);
return;
}
JsonSerializer<Object> ser = _valueSerializer;
if (ser == null) {
Class<?> c = value.getClass();
/* 10-Mar-2010, tatu: Ideally we would actually separate out type
* serializer from value serializer; but, alas, there's no access
* to serializer factory at this point...
*/
// let's cache it, may be needed soon again
ser = prov.findTypedValueSerializer(c, true, _property);
}
ser.serialize(value, jgen, prov);
} catch (IOException ioe) {
throw ioe;
} catch (Exception e) {
Throwable t = e;
// Need to unwrap this specific type, to see infinite recursion...
while (t instanceof InvocationTargetException && t.getCause() != null) {
t = t.getCause();
}
// Errors shouldn't be wrapped (and often can't, as well)
if (t instanceof Error) {
throw (Error) t;
}
// let's try to indicate the path best we can...
throw JsonMappingException.wrapWithPath(t, bean, _accessorMethod.getName() + "()");
}
}
@Override
public void serializeWithType(Object bean, JsonGenerator jgen, SerializerProvider provider,
TypeSerializer typeSer0)
throws IOException, JsonProcessingException
{
// Regardless of other parts, first need to find value to serialize:
Object value = null;
try {
value = _accessorMethod.invoke(bean);
// and if we got null, can also just write it directly
if (value == null) {
provider.defaultSerializeNull(jgen);
return;
}
JsonSerializer<Object> ser = _valueSerializer;
if (ser == null) { // already got a serializer? fabulous, that be easy...
// ser = provider.findTypedValueSerializer(value.getClass(), true, _property);
ser = provider.findValueSerializer(value.getClass(), _property);
} else {
/* 09-Dec-2010, tatu: To work around natural type's refusal to add type info, we do
* this (note: type is for the wrapper type, not enclosed value!)
*/
if (_forceTypeInformation) {
typeSer0.writeTypePrefixForScalar(bean, jgen);
ser.serialize(value, jgen, provider);
typeSer0.writeTypeSuffixForScalar(bean, jgen);
return;
}
}
// and then redirect type id lookups
TypeSerializer typeSer = new TypeSerializerWrapper(typeSer0, bean);
ser.serializeWithType(value, jgen, provider, typeSer);
} catch (IOException ioe) {
throw ioe;
} catch (Exception e) {
Throwable t = e;
// Need to unwrap this specific type, to see infinite recursion...
while (t instanceof InvocationTargetException && t.getCause() != null) {
t = t.getCause();
}
// Errors shouldn't be wrapped (and often can't, as well)
if (t instanceof Error) {
throw (Error) t;
}
// let's try to indicate the path best we can...
throw JsonMappingException.wrapWithPath(t, bean, _accessorMethod.getName() + "()");
}
}
@Override
public JsonNode getSchema(SerializerProvider provider, Type typeHint)
throws JsonMappingException
{
return (_valueSerializer instanceof SchemaAware) ?
((SchemaAware) _valueSerializer).getSchema(provider, null) :
com.fasterxml.jackson.databind.jsonschema.JsonSchema.getDefaultSchemaNode();
}
@Override
public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType typeHint)
throws JsonMappingException
{
if (_valueSerializer != null) {
_valueSerializer.acceptJsonFormatVisitor(visitor, null);
} else {
visitor.expectAnyFormat(typeHint);
}
}
protected boolean isNaturalTypeWithStdHandling(Class<?> rawType, JsonSerializer<?> ser)
{
// First: do we have a natural type being handled?
if (rawType.isPrimitive()) {
if (rawType != Integer.TYPE && rawType != Boolean.TYPE && rawType != Double.TYPE) {
return false;
}
} else {
if (rawType != String.class &&
rawType != Integer.class && rawType != Boolean.class && rawType != Double.class) {
return false;
}
}
return isDefaultSerializer(ser);
}
/*
/**********************************************************
/* Other methods
/**********************************************************
*/
@Override
public String toString()
{
return "(@JsonValue serializer for method " + _accessorMethod.getDeclaringClass() + "#" + _accessorMethod.getName() + ")";
}
}