/**
* Return the Jackson {@link JavaType} for the specified type and context class.
*
* <p>The default implementation returns {@code typeFactory.constructType(type, contextClass)},
* but this can be overridden in subclasses, to allow for custom generic collection handling. For
* instance:
*
* <pre class="code">
* protected JavaType getJavaType(Type type) {
* if (type instanceof Class && List.class.isAssignableFrom((Class)type)) {
* return TypeFactory.collectionType(ArrayList.class, MyBean.class);
* } else {
* return super.getJavaType(type);
* }
* }
* </pre>
*
* @param type the generic type to return the Jackson JavaType for
* @param contextClass a context class for the target type, for example a class in which the
* target type appears in a method signature (can be {@code null})
* @return the Jackson JavaType
*/
protected JavaType getJavaType(Type type, Class<?> contextClass) {
TypeFactory typeFactory = this.objectMapper.getTypeFactory();
if (type instanceof TypeVariable && contextClass != null) {
ResolvableType resolvedType =
resolveVariable((TypeVariable<?>) type, ResolvableType.forClass(contextClass));
if (resolvedType != ResolvableType.NONE) {
return typeFactory.constructType(resolvedType.resolve());
}
}
return typeFactory.constructType(type);
}
private Flux<Object> decodeInternal(
JsonObjectDecoder objectDecoder,
Publisher<DataBuffer> inputStream,
ResolvableType elementType,
MimeType mimeType,
Object[] hints) {
Assert.notNull(inputStream, "'inputStream' must not be null");
Assert.notNull(elementType, "'elementType' must not be null");
TypeFactory typeFactory = this.mapper.getTypeFactory();
JavaType javaType = typeFactory.constructType(elementType.getType());
ObjectReader reader = this.mapper.readerFor(javaType);
return objectDecoder
.decode(inputStream, elementType, mimeType, hints)
.map(
dataBuffer -> {
try {
Object value = reader.readValue(dataBuffer.asInputStream());
DataBufferUtils.release(dataBuffer);
return value;
} catch (IOException e) {
return Flux.error(new CodecException("Error while reading the data", e));
}
});
}
public <T> T copy(T input) throws ObjectCopyException {
try {
byte[] bytes = mapper.writeValueAsBytes(input);
TypeFactory tf = mapper.getTypeFactory();
JavaType type = tf.constructType(input.getClass());
return mapper.readValue(bytes, type);
} catch (IOException e) {
log.error("error in copying input", e);
throw new ObjectCopyException("error in copying input", e);
}
}
/**
* Invokes the given method on the {@code handler} passing the given params (after converting them
* to beans\objects) to it.
*
* @param m the method to invoke
* @param params the params to pass to the method
* @return the return value (or null if no return)
* @throws IOException on error
* @throws IllegalAccessException on error
* @throws InvocationTargetException on error
*/
protected JsonNode invoke(Method m, List<JsonNode> params)
throws IOException, IllegalAccessException, InvocationTargetException {
// debug log
if (LOGGER.isLoggable(Level.FINE)) {
LOGGER.log(Level.FINE, "Invoking method: " + m.getName());
}
// convert the parameters
Object[] convertedParams = new Object[params.size()];
Type[] parameterTypes = m.getGenericParameterTypes();
for (int i = 0; i < parameterTypes.length; i++) {
JsonParser paramJsonParser = mapper.treeAsTokens(params.get(i));
JavaType paramJavaType = TypeFactory.defaultInstance().constructType(parameterTypes[i]);
convertedParams[i] = mapper.readValue(paramJsonParser, paramJavaType);
}
// invoke the method
Object result = m.invoke(handler, convertedParams);
Type genericReturnType = m.getGenericReturnType();
if (genericReturnType != null) {
if (Collection.class.isInstance(result) && genericReturnType instanceof ParameterizedType) {
try {
if (LOGGER.isLoggable(Level.FINE)) {
LOGGER.log(Level.FINE, "attempting custom collection serialization");
}
TypeFactory typeFactory = mapper.getTypeFactory();
Type actualTypeInCollection =
((ParameterizedType) genericReturnType).getActualTypeArguments()[0];
if (actualTypeInCollection
instanceof TypeVariable) { // collection actually has a generic return type
actualTypeInCollection = ((TypeVariable) actualTypeInCollection).getBounds()[0];
}
JavaType rootType =
typeFactory.constructCollectionType(
Collection.class, typeFactory.constructType(actualTypeInCollection));
return valueToTree(mapper.writerWithType(rootType), result);
} catch (Exception e) {
LOGGER.log(
Level.WARNING,
"could not do custom collection serialization falling back to default",
e);
}
}
return mapper.valueToTree(result);
} else {
return null;
}
// return (genericReturnType!=null) ? mapper.valueToTree(result) : null;
}
/**
* Method that can be used to find out actual output (target) type; this usually can be determined
* from type parameters, but may need to be implemented differently from programmatically defined
* converters (which can not change static type parameter bindings).
*
* @param typeFactory
* @since 2.2
*/
@Override
public JavaType getOutputType(TypeFactory typeFactory) {
return typeFactory.constructType(ResponseCode.class);
}
/**
* Method that can be used to find out actual input (source) type; this usually can be determined
* from type parameters, but may need to be implemented differently from programmatically defined
* converters (which can not change static type parameter bindings).
*
* @param typeFactory
* @since 2.2
*/
@Override
public JavaType getInputType(TypeFactory typeFactory) {
return typeFactory.constructType(Integer.class);
}
public static JavaType buildType(final Class<?> simple) {
return typeFactory.constructType(simple);
}