| /* |
| * Copyright (C) 2015 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 com.android.car; |
| |
| import android.annotation.Nullable; |
| import android.os.IBinder; |
| import android.os.IInterface; |
| import android.os.RemoteException; |
| |
| import com.android.internal.annotations.GuardedBy; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| /** |
| * Helper class to hold client's binder interface. |
| * |
| * @param <T> type of the value that is wrapped by this class |
| */ |
| public class BinderInterfaceContainer<T extends IInterface> { |
| |
| /** |
| * Wrapper class for objects that want to be notified whenever they are unliked from |
| * the container ({@link BinderInterfaceContainer}). |
| * |
| * @param <T> type of the value that is wrapped by this class |
| */ |
| public static class BinderInterface<T extends IInterface> implements IBinder.DeathRecipient { |
| public final T binderInterface; |
| private final BinderInterfaceContainer<T> mContainer; |
| |
| public BinderInterface(BinderInterfaceContainer<T> container, T binderInterface) { |
| mContainer = container; |
| this.binderInterface = binderInterface; |
| } |
| |
| @Override |
| public void binderDied() { |
| binderInterface.asBinder().unlinkToDeath(this, 0); |
| mContainer.handleBinderDeath(this); |
| } |
| } |
| |
| /** |
| * Interface to be implemented by object that want to be notified whenever a binder is unliked |
| * (dies). |
| */ |
| public interface BinderEventHandler<T extends IInterface> { |
| void onBinderDeath(BinderInterface<T> bInterface); |
| } |
| |
| private final Object mLock = new Object(); |
| |
| private final BinderEventHandler<T> mEventHandler; |
| |
| @GuardedBy("mLock") |
| private final Map<IBinder, BinderInterface<T>> mBinders = new HashMap<>(); |
| |
| /** |
| * Constructs a new <code>BinderInterfaceContainer</code> passing an event handler to be used to |
| * notify listeners when a registered binder dies (unlinked). |
| */ |
| public BinderInterfaceContainer(@Nullable BinderEventHandler<T> eventHandler) { |
| mEventHandler = eventHandler; |
| } |
| |
| public BinderInterfaceContainer() { |
| mEventHandler = null; |
| } |
| |
| /** |
| * Add the instance of {@link IInterface} representing the binder interface to this container. |
| * |
| * Internally, this object will be wrapped in an {@link BinderInterface} when added. |
| */ |
| public void addBinder(T binderInterface) { |
| IBinder binder = binderInterface.asBinder(); |
| synchronized (mLock) { |
| BinderInterface<T> bInterface = mBinders.get(binder); |
| if (bInterface != null) { |
| return; |
| } |
| bInterface = new BinderInterface<T>(this, binderInterface); |
| try { |
| binder.linkToDeath(bInterface, 0); |
| } catch (RemoteException e) { |
| throw new IllegalArgumentException(e); |
| } |
| mBinders.put(binder, bInterface); |
| } |
| } |
| |
| /** |
| * Removes the {@link BinderInterface} object associated with the passed parameter (if there is |
| * any). |
| */ |
| public void removeBinder(T binderInterface) { |
| IBinder binder = binderInterface.asBinder(); |
| synchronized (mLock) { |
| BinderInterface<T> bInterface = mBinders.get(binder); |
| if (bInterface == null) { |
| return; |
| } |
| binder.unlinkToDeath(bInterface, 0); |
| mBinders.remove(binder); |
| } |
| } |
| |
| /** |
| * Returns the {@link BinderInterface} object associated with the passed parameter. |
| */ |
| public BinderInterface<T> getBinderInterface(T binderInterface) { |
| IBinder binder = binderInterface.asBinder(); |
| synchronized (mLock) { |
| return mBinders.get(binder); |
| } |
| } |
| |
| /** |
| * Adds a new {@link BinderInterface} in this container. |
| */ |
| public void addBinderInterface(BinderInterface<T> bInterface) { |
| IBinder binder = bInterface.binderInterface.asBinder(); |
| synchronized (mLock) { |
| try { |
| binder.linkToDeath(bInterface, 0); |
| } catch (RemoteException e) { |
| throw new IllegalArgumentException(e); |
| } |
| mBinders.put(binder, bInterface); |
| } |
| } |
| |
| /** |
| * Returns a shallow copy of all registered {@link BinderInterface} objects in this container. |
| */ |
| public Collection<BinderInterface<T>> getInterfaces() { |
| synchronized (mLock) { |
| return new ArrayList<>(mBinders.values()); |
| } |
| } |
| |
| /** |
| * Returns the number of registered {@link BinderInterface} objects in this container. |
| */ |
| public int size() { |
| synchronized (mLock) { |
| return mBinders.size(); |
| } |
| } |
| |
| /** |
| * Clears all registered {@link BinderInterface} objects. |
| */ |
| public void clear() { |
| synchronized (mLock) { |
| Collection<BinderInterface<T>> interfaces = getInterfaces(); |
| for (BinderInterface<T> bInterface : interfaces) { |
| IBinder binder = bInterface.binderInterface.asBinder(); |
| binder.unlinkToDeath(bInterface, 0); |
| } |
| } |
| mBinders.clear(); |
| } |
| |
| private void handleBinderDeath(BinderInterface<T> bInterface) { |
| if (mEventHandler != null) { |
| mEventHandler.onBinderDeath(bInterface); |
| } |
| removeBinder(bInterface.binderInterface); |
| } |
| } |