feign.hystrix.HystrixDelegatingContract Maven / Gradle / Ivy
/*
* Copyright © 2012 The Feign Authors ([email protected])
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package feign.hystrix;
import static feign.Util.resolveLastTypeParameter;
import com.netflix.hystrix.HystrixCommand;
import feign.Contract;
import feign.MethodMetadata;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import rx.Completable;
import rx.Observable;
import rx.Single;
/**
* This special cases methods that return {@link HystrixCommand}, {@link Observable}, or {@link
* Single} so that they are decoded properly.
*
* For example, {@literal HystrixCommand} and {@literal Observable} will decode {@code
* Foo}.
*/
// Visible for use in custom Hystrix invocation handlers
public final class HystrixDelegatingContract implements Contract {
private final Contract delegate;
public HystrixDelegatingContract(Contract delegate) {
this.delegate = delegate;
}
@Override
public List parseAndValidateMetadata(Class targetType) {
List metadatas = this.delegate.parseAndValidateMetadata(targetType);
for (MethodMetadata metadata : metadatas) {
Type type = metadata.returnType();
if (type instanceof ParameterizedType
&& ((ParameterizedType) type).getRawType().equals(HystrixCommand.class)) {
Type actualType = resolveLastTypeParameter(type, HystrixCommand.class);
metadata.returnType(actualType);
} else if (type instanceof ParameterizedType
&& ((ParameterizedType) type).getRawType().equals(Observable.class)) {
Type actualType = resolveLastTypeParameter(type, Observable.class);
metadata.returnType(actualType);
} else if (type instanceof ParameterizedType
&& ((ParameterizedType) type).getRawType().equals(Single.class)) {
Type actualType = resolveLastTypeParameter(type, Single.class);
metadata.returnType(actualType);
} else if (type instanceof ParameterizedType
&& ((ParameterizedType) type).getRawType().equals(Completable.class)) {
metadata.returnType(void.class);
} else if (type instanceof ParameterizedType
&& ((ParameterizedType) type).getRawType().equals(CompletableFuture.class)) {
metadata.returnType(resolveLastTypeParameter(type, CompletableFuture.class));
}
}
return metadatas;
}
}