/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.falcon.resource.channel;
import org.apache.falcon.FalconException;
import java.lang.reflect.Method;
import java.util.concurrent.ConcurrentHashMap;
/**
* A base class for Channel.
*/
public abstract class AbstractChannel implements Channel {
private final ConcurrentHashMap<MethodKey, Method> methods = new ConcurrentHashMap<MethodKey, Method>();
protected Method getMethod(Class service, String methodName, Object... args)
throws FalconException {
MethodKey methodKey = new MethodKey(methodName, args);
Method method = methods.get(methodKey);
if (method == null) {
for (Method item : service.getDeclaredMethods()) {
MethodKey itemKey = new MethodKey(item.getName(),
item.getParameterTypes());
if (methodKey.equals(itemKey)) {
methods.putIfAbsent(methodKey, item);
return methods.get(methodKey);
}
}
throw new FalconException("Lookup for " + methodKey
+ " in service " + service.getName() + " found no match");
}
return method;
}
}