Brett Chabot | 9c27c90 | 2013-09-27 11:00:56 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2013 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package com.android.tradefed.command.remote; |
| 17 | |
| 18 | import com.android.tradefed.device.ITestDevice; |
| 19 | |
| 20 | import java.util.ArrayList; |
| 21 | import java.util.Collection; |
| 22 | import java.util.Hashtable; |
| 23 | import java.util.Map; |
| 24 | |
| 25 | /** |
| 26 | * Singleton class that tracks devices that have been remotely allocated. |
| 27 | */ |
| 28 | class DeviceTracker { |
| 29 | |
| 30 | /** |
| 31 | * Use on demand holder idiom |
| 32 | * @see http://en.wikipedia.org/wiki/Singleton_pattern#The_solution_of_Bill_Pugh |
| 33 | */ |
| 34 | private static class SingletonHolder { |
| 35 | public static final DeviceTracker cInstance = new DeviceTracker(); |
| 36 | } |
| 37 | |
| 38 | public static DeviceTracker getInstance() { |
| 39 | return SingletonHolder.cInstance; |
| 40 | } |
| 41 | |
| 42 | // private constructor - don't allow instantiation |
| 43 | private DeviceTracker() { |
| 44 | } |
| 45 | |
| 46 | // use Hashtable since its thread-safe |
| 47 | private Map<String, ITestDevice> mAllocatedDeviceMap = new Hashtable<String, ITestDevice>(); |
| 48 | |
| 49 | /** |
| 50 | * Mark given device as remotely allocated. |
| 51 | */ |
| 52 | public void allocateDevice(ITestDevice d) { |
| 53 | mAllocatedDeviceMap.put(d.getSerialNumber(), d); |
| 54 | } |
| 55 | |
| 56 | /** |
| 57 | * Mark given device serial as freed. |
| 58 | * |
| 59 | * @return the corresponding {@link ITestDevice} or <code>null</code> if device with given |
| 60 | * serial cannot be found |
| 61 | */ |
| 62 | public ITestDevice freeDevice(String serial) { |
| 63 | return mAllocatedDeviceMap.remove(serial); |
| 64 | } |
| 65 | |
| 66 | /** |
| 67 | * Mark all remotely allocated devices as freed. |
| 68 | * |
| 69 | * @return a {@link Collection} of all remotely allocated devices |
| 70 | */ |
| 71 | public Collection<ITestDevice> freeAll() { |
| 72 | Collection<ITestDevice> devices = new ArrayList<ITestDevice>(mAllocatedDeviceMap.values()); |
| 73 | mAllocatedDeviceMap.clear(); |
| 74 | return devices; |
| 75 | } |
| 76 | } |