InstallationContext.java

/**
 * Copyright (C) 2010 Daniel Manzke <daniel.manzke@googlemail.com>
 *
 * 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 de.devsurf.injection.guice.install;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Callable;

/**
 * This class is internally used, to bind Installation Requests and process them
 * sequentially in a predefined order.
 * 
 * @author Daniel Manzke
 * 
 */
public class InstallationContext {
	private Map<BindingStage, List<Callable<?>>> context = new HashMap<BindingStage, List<Callable<?>>>();

	public void process() throws Exception {
		for (BindingStage stage : BindingStage.ORDERED) {
			List<Callable<?>> requests = context.get(stage);
			if (requests != null) {
				for (Callable<?> request : requests) {
					request.call();
				}
			}
		}
	}

	public void add(BindingStage stage, Callable<?> request) {
		synchronized (context) {
			List<Callable<?>> requests = context.get(stage);
			if (requests == null) {
				requests = new ArrayList<Callable<?>>();
				context.put(stage, requests);
			}
			requests.add(request);
		}
	}

	public void add(StageableRequest request) {
		synchronized (context) {
			List<Callable<?>> requests = context.get(request.getExecutionStage());
			if (requests == null) {
				requests = new ArrayList<Callable<?>>();
				context.put(request.getExecutionStage(), requests);
			}
			requests.add(request);
		}
	}

	public static interface StageableRequest extends java.util.concurrent.Callable<Void> {
		BindingStage getExecutionStage();
	}

}