| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * 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 android.filterfw.core; |
| |
| import android.filterfw.core.Filter; |
| import android.filterfw.core.RoundRobinScheduler; |
| import android.util.Log; |
| |
| import java.util.HashMap; |
| |
| /** |
| * This OneShotScheduler only schedules source filters at most once. All other |
| * filters will be scheduled, and possibly repeatedly, until there is no filter |
| * that can be scheduled. |
| * |
| * @hide |
| */ |
| public class OneShotScheduler extends RoundRobinScheduler { |
| private HashMap <String, Integer> scheduled; |
| |
| private final boolean mLogVerbose; |
| private static final String TAG = "OneShotScheduler"; |
| |
| public OneShotScheduler(FilterGraph graph) { |
| super(graph); |
| scheduled = new HashMap<String, Integer>(); |
| mLogVerbose = Log.isLoggable(TAG, Log.VERBOSE); |
| } |
| |
| @Override |
| public void reset() { |
| super.reset(); |
| scheduled.clear(); |
| } |
| |
| @Override |
| public Filter scheduleNextNode() { |
| Filter first = null; |
| // return the first filter that is not scheduled before. |
| while (true) { |
| Filter filter = super.scheduleNextNode(); |
| if (filter == null) { |
| if (mLogVerbose) Log.v(TAG, "No filters available to run."); |
| return null; |
| } |
| if (!scheduled.containsKey(filter.getName())) { |
| if (filter.getNumberOfConnectedInputs() == 0) |
| scheduled.put(filter.getName(),1); |
| if (mLogVerbose) Log.v(TAG, "Scheduling filter \"" + filter.getName() + "\" of type " + filter.getFilterClassName()); |
| return filter; |
| } |
| // if loop back, nothing available |
| if (first == filter) { |
| break; |
| } |
| // save the first scheduled one |
| if (first == null) first = filter; |
| } |
| if (mLogVerbose) Log.v(TAG, "One pass through graph completed."); |
| return null; |
| } |
| } |