commit
a9db97c359
@ -0,0 +1,513 @@ |
||||
/* |
||||
* Copyright (c) 2014 Badoo Trading Limited |
||||
* Permission is hereby granted, free of charge, to any person obtaining a copy |
||||
* of this software and associated documentation files (the "Software"), to deal |
||||
* in the Software without restriction, including without limitation the rights |
||||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
||||
* copies of the Software, and to permit persons to whom the Software is |
||||
* furnished to do so, subject to the following conditions: |
||||
* |
||||
* The above copyright notice and this permission notice shall be included in |
||||
* all copies or substantial portions of the Software. |
||||
* |
||||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
||||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
||||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
||||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
||||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
||||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
||||
* THE SOFTWARE. |
||||
* |
||||
* Portions of documentation in this code are modifications based on work created and |
||||
* shared by Android Open Source Project and used according to terms described in the |
||||
* Apache License, Version 2.0 |
||||
*/ |
||||
package com.arialyy.aria.util; |
||||
|
||||
import android.os.Handler; |
||||
import android.os.Looper; |
||||
import android.os.Message; |
||||
import android.support.annotation.NonNull; |
||||
import android.support.annotation.Nullable; |
||||
import android.support.annotation.VisibleForTesting; |
||||
|
||||
import java.lang.ref.WeakReference; |
||||
import java.util.concurrent.locks.Lock; |
||||
import java.util.concurrent.locks.ReentrantLock; |
||||
|
||||
/** |
||||
* Memory safer implementation of android.os.Handler |
||||
* Original implementation of Handlers always keeps hard reference to handler in queue of execution. |
||||
* If you create anonymous handler and post delayed message into it, it will keep all parent class
|
||||
* for that time in memory even if it could be cleaned. |
||||
* This implementation is trickier, it will keep WeakReferences to runnables and messages, |
||||
* and GC could collect them once WeakHandler instance is not referenced any more |
||||
* |
||||
* @see android.os.Handler |
||||
* |
||||
* Created by Dmytro Voronkevych on 17/06/2014. |
||||
*/ |
||||
@SuppressWarnings("unused") |
||||
public class WeakHandler { |
||||
private final Handler.Callback mCallback; // hard reference to Callback. We need to keep callback in memory
|
||||
private final ExecHandler mExec; |
||||
private Lock mLock = new ReentrantLock(); |
||||
@SuppressWarnings("ConstantConditions") |
||||
@VisibleForTesting |
||||
final ChainedRef mRunnables = new ChainedRef(mLock, null); |
||||
|
||||
/** |
||||
* Default constructor associates this handler with the {@link Looper} for the |
||||
* current thread. |
||||
* |
||||
* If this thread does not have a looper, this handler won't be able to receive messages |
||||
* so an exception is thrown. |
||||
*/ |
||||
public WeakHandler() { |
||||
mCallback = null; |
||||
mExec = new ExecHandler(); |
||||
} |
||||
|
||||
/** |
||||
* Constructor associates this handler with the {@link Looper} for the |
||||
* current thread and takes a callback interface in which you can handle |
||||
* messages. |
||||
* |
||||
* If this thread does not have a looper, this handler won't be able to receive messages |
||||
* so an exception is thrown. |
||||
* |
||||
* @param callback The callback interface in which to handle messages, or null. |
||||
*/ |
||||
public WeakHandler(@Nullable Handler.Callback callback) { |
||||
mCallback = callback; // Hard referencing body
|
||||
mExec = new ExecHandler(new WeakReference<>(callback)); // Weak referencing inside ExecHandler
|
||||
} |
||||
|
||||
/** |
||||
* Use the provided {@link Looper} instead of the default one. |
||||
* |
||||
* @param looper The looper, must not be null. |
||||
*/ |
||||
public WeakHandler(@NonNull Looper looper) { |
||||
mCallback = null; |
||||
mExec = new ExecHandler(looper); |
||||
} |
||||
|
||||
/** |
||||
* Use the provided {@link Looper} instead of the default one and take a callback |
||||
* interface in which to handle messages. |
||||
* |
||||
* @param looper The looper, must not be null. |
||||
* @param callback The callback interface in which to handle messages, or null. |
||||
*/ |
||||
public WeakHandler(@NonNull Looper looper, @NonNull Handler.Callback callback) { |
||||
mCallback = callback; |
||||
mExec = new ExecHandler(looper, new WeakReference<>(callback)); |
||||
} |
||||
|
||||
/** |
||||
* Causes the Runnable r to be added to the message queue. |
||||
* The runnable will be run on the thread to which this handler is |
||||
* attached. |
||||
* |
||||
* @param r The Runnable that will be executed. |
||||
* |
||||
* @return Returns true if the Runnable was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. |
||||
*/ |
||||
public final boolean post(@NonNull Runnable r) { |
||||
return mExec.post(wrapRunnable(r)); |
||||
} |
||||
|
||||
/** |
||||
* Causes the Runnable r to be added to the message queue, to be run |
||||
* at a specific time given by <var>uptimeMillis</var>. |
||||
* <b>The time-base is {@link android.os.SystemClock#uptimeMillis}.</b> |
||||
* The runnable will be run on the thread to which this handler is attached. |
||||
* |
||||
* @param r The Runnable that will be executed. |
||||
* @param uptimeMillis The absolute time at which the callback should run, |
||||
* using the {@link android.os.SystemClock#uptimeMillis} time-base. |
||||
* |
||||
* @return Returns true if the Runnable was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. Note that a |
||||
* result of true does not mean the Runnable will be processed -- if |
||||
* the looper is quit before the delivery time of the message |
||||
* occurs then the message will be dropped. |
||||
*/ |
||||
public final boolean postAtTime(@NonNull Runnable r, long uptimeMillis) { |
||||
return mExec.postAtTime(wrapRunnable(r), uptimeMillis); |
||||
} |
||||
|
||||
/** |
||||
* Causes the Runnable r to be added to the message queue, to be run |
||||
* at a specific time given by <var>uptimeMillis</var>. |
||||
* <b>The time-base is {@link android.os.SystemClock#uptimeMillis}.</b> |
||||
* The runnable will be run on the thread to which this handler is attached. |
||||
* |
||||
* @param r The Runnable that will be executed. |
||||
* @param uptimeMillis The absolute time at which the callback should run, |
||||
* using the {@link android.os.SystemClock#uptimeMillis} time-base. |
||||
* |
||||
* @return Returns true if the Runnable was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. Note that a |
||||
* result of true does not mean the Runnable will be processed -- if |
||||
* the looper is quit before the delivery time of the message |
||||
* occurs then the message will be dropped. |
||||
* |
||||
* @see android.os.SystemClock#uptimeMillis |
||||
*/ |
||||
public final boolean postAtTime(Runnable r, Object token, long uptimeMillis) { |
||||
return mExec.postAtTime(wrapRunnable(r), token, uptimeMillis); |
||||
} |
||||
|
||||
/** |
||||
* Causes the Runnable r to be added to the message queue, to be run |
||||
* after the specified amount of time elapses. |
||||
* The runnable will be run on the thread to which this handler |
||||
* is attached. |
||||
* |
||||
* @param r The Runnable that will be executed. |
||||
* @param delayMillis The delay (in milliseconds) until the Runnable |
||||
* will be executed. |
||||
* |
||||
* @return Returns true if the Runnable was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. Note that a |
||||
* result of true does not mean the Runnable will be processed -- |
||||
* if the looper is quit before the delivery time of the message |
||||
* occurs then the message will be dropped. |
||||
*/ |
||||
public final boolean postDelayed(Runnable r, long delayMillis) { |
||||
return mExec.postDelayed(wrapRunnable(r), delayMillis); |
||||
} |
||||
|
||||
/** |
||||
* Posts a message to an object that implements Runnable. |
||||
* Causes the Runnable r to executed on the next iteration through the |
||||
* message queue. The runnable will be run on the thread to which this |
||||
* handler is attached. |
||||
* <b>This method is only for use in very special circumstances -- it |
||||
* can easily starve the message queue, cause ordering problems, or have |
||||
* other unexpected side-effects.</b> |
||||
* |
||||
* @param r The Runnable that will be executed. |
||||
* |
||||
* @return Returns true if the message was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. |
||||
*/ |
||||
public final boolean postAtFrontOfQueue(Runnable r) { |
||||
return mExec.postAtFrontOfQueue(wrapRunnable(r)); |
||||
} |
||||
|
||||
/** |
||||
* Remove any pending posts of Runnable r that are in the message queue. |
||||
*/ |
||||
public final void removeCallbacks(Runnable r) { |
||||
final WeakRunnable runnable = mRunnables.remove(r); |
||||
if (runnable != null) { |
||||
mExec.removeCallbacks(runnable); |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Remove any pending posts of Runnable <var>r</var> with Object |
||||
* <var>token</var> that are in the message queue. If <var>token</var> is null, |
||||
* all callbacks will be removed. |
||||
*/ |
||||
public final void removeCallbacks(Runnable r, Object token) { |
||||
final WeakRunnable runnable = mRunnables.remove(r); |
||||
if (runnable != null) { |
||||
mExec.removeCallbacks(runnable, token); |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Pushes a message onto the end of the message queue after all pending messages |
||||
* before the current time. It will be received in callback, |
||||
* in the thread attached to this handler. |
||||
* |
||||
* @return Returns true if the message was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. |
||||
*/ |
||||
public final boolean sendMessage(Message msg) { |
||||
return mExec.sendMessage(msg); |
||||
} |
||||
|
||||
/** |
||||
* Sends a Message containing only the what value. |
||||
* |
||||
* @return Returns true if the message was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. |
||||
*/ |
||||
public final boolean sendEmptyMessage(int what) { |
||||
return mExec.sendEmptyMessage(what); |
||||
} |
||||
|
||||
/** |
||||
* Sends a Message containing only the what value, to be delivered |
||||
* after the specified amount of time elapses. |
||||
* @see #sendMessageDelayed(android.os.Message, long) |
||||
* |
||||
* @return Returns true if the message was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. |
||||
*/ |
||||
public final boolean sendEmptyMessageDelayed(int what, long delayMillis) { |
||||
return mExec.sendEmptyMessageDelayed(what, delayMillis); |
||||
} |
||||
|
||||
/** |
||||
* Sends a Message containing only the what value, to be delivered |
||||
* at a specific time. |
||||
* @see #sendMessageAtTime(android.os.Message, long) |
||||
* |
||||
* @return Returns true if the message was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. |
||||
*/ |
||||
public final boolean sendEmptyMessageAtTime(int what, long uptimeMillis) { |
||||
return mExec.sendEmptyMessageAtTime(what, uptimeMillis); |
||||
} |
||||
|
||||
/** |
||||
* Enqueue a message into the message queue after all pending messages |
||||
* before (current time + delayMillis). You will receive it in |
||||
* callback, in the thread attached to this handler. |
||||
* |
||||
* @return Returns true if the message was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. Note that a |
||||
* result of true does not mean the message will be processed -- if |
||||
* the looper is quit before the delivery time of the message |
||||
* occurs then the message will be dropped. |
||||
*/ |
||||
public final boolean sendMessageDelayed(Message msg, long delayMillis) { |
||||
return mExec.sendMessageDelayed(msg, delayMillis); |
||||
} |
||||
|
||||
/** |
||||
* Enqueue a message into the message queue after all pending messages |
||||
* before the absolute time (in milliseconds) <var>uptimeMillis</var>. |
||||
* <b>The time-base is {@link android.os.SystemClock#uptimeMillis}.</b> |
||||
* You will receive it in callback, in the thread attached |
||||
* to this handler. |
||||
* |
||||
* @param uptimeMillis The absolute time at which the message should be |
||||
* delivered, using the |
||||
* {@link android.os.SystemClock#uptimeMillis} time-base. |
||||
* |
||||
* @return Returns true if the message was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. Note that a |
||||
* result of true does not mean the message will be processed -- if |
||||
* the looper is quit before the delivery time of the message |
||||
* occurs then the message will be dropped. |
||||
*/ |
||||
public boolean sendMessageAtTime(Message msg, long uptimeMillis) { |
||||
return mExec.sendMessageAtTime(msg, uptimeMillis); |
||||
} |
||||
|
||||
/** |
||||
* Enqueue a message at the front of the message queue, to be processed on |
||||
* the next iteration of the message loop. You will receive it in |
||||
* callback, in the thread attached to this handler. |
||||
* <b>This method is only for use in very special circumstances -- it |
||||
* can easily starve the message queue, cause ordering problems, or have |
||||
* other unexpected side-effects.</b> |
||||
* |
||||
* @return Returns true if the message was successfully placed in to the |
||||
* message queue. Returns false on failure, usually because the |
||||
* looper processing the message queue is exiting. |
||||
*/ |
||||
public final boolean sendMessageAtFrontOfQueue(Message msg) { |
||||
return mExec.sendMessageAtFrontOfQueue(msg); |
||||
} |
||||
|
||||
/** |
||||
* Remove any pending posts of messages with code 'what' that are in the |
||||
* message queue. |
||||
*/ |
||||
public final void removeMessages(int what) { |
||||
mExec.removeMessages(what); |
||||
} |
||||
|
||||
/** |
||||
* Remove any pending posts of messages with code 'what' and whose obj is |
||||
* 'object' that are in the message queue. If <var>object</var> is null, |
||||
* all messages will be removed. |
||||
*/ |
||||
public final void removeMessages(int what, Object object) { |
||||
mExec.removeMessages(what, object); |
||||
} |
||||
|
||||
/** |
||||
* Remove any pending posts of callbacks and sent messages whose |
||||
* <var>obj</var> is <var>token</var>. If <var>token</var> is null, |
||||
* all callbacks and messages will be removed. |
||||
*/ |
||||
public final void removeCallbacksAndMessages(Object token) { |
||||
mExec.removeCallbacksAndMessages(token); |
||||
} |
||||
|
||||
/** |
||||
* Check if there are any pending posts of messages with code 'what' in |
||||
* the message queue. |
||||
*/ |
||||
public final boolean hasMessages(int what) { |
||||
return mExec.hasMessages(what); |
||||
} |
||||
|
||||
/** |
||||
* Check if there are any pending posts of messages with code 'what' and |
||||
* whose obj is 'object' in the message queue. |
||||
*/ |
||||
public final boolean hasMessages(int what, Object object) { |
||||
return mExec.hasMessages(what, object); |
||||
} |
||||
|
||||
public final Looper getLooper() { |
||||
return mExec.getLooper(); |
||||
} |
||||
|
||||
private WeakRunnable wrapRunnable(@NonNull Runnable r) { |
||||
//noinspection ConstantConditions
|
||||
if (r == null) { |
||||
throw new NullPointerException("Runnable can't be null"); |
||||
} |
||||
final ChainedRef hardRef = new ChainedRef(mLock, r); |
||||
mRunnables.insertAfter(hardRef); |
||||
return hardRef.wrapper; |
||||
} |
||||
|
||||
private static class ExecHandler extends Handler { |
||||
private final WeakReference<Handler.Callback> mCallback; |
||||
|
||||
ExecHandler() { |
||||
mCallback = null; |
||||
} |
||||
|
||||
ExecHandler(WeakReference<Handler.Callback> callback) { |
||||
mCallback = callback; |
||||
} |
||||
|
||||
ExecHandler(Looper looper) { |
||||
super(looper); |
||||
mCallback = null; |
||||
} |
||||
|
||||
ExecHandler(Looper looper, WeakReference<Handler.Callback> callback) { |
||||
super(looper); |
||||
mCallback = callback; |
||||
} |
||||
|
||||
@Override |
||||
public void handleMessage(@NonNull Message msg) { |
||||
if (mCallback == null) { |
||||
return; |
||||
} |
||||
final Handler.Callback callback = mCallback.get(); |
||||
if (callback == null) { // Already disposed
|
||||
return; |
||||
} |
||||
callback.handleMessage(msg); |
||||
} |
||||
} |
||||
|
||||
static class WeakRunnable implements Runnable { |
||||
private final WeakReference<Runnable> mDelegate; |
||||
private final WeakReference<ChainedRef> mReference; |
||||
|
||||
WeakRunnable(WeakReference<Runnable> delegate, WeakReference<ChainedRef> reference) { |
||||
mDelegate = delegate; |
||||
mReference = reference; |
||||
} |
||||
|
||||
@Override |
||||
public void run() { |
||||
final Runnable delegate = mDelegate.get(); |
||||
final ChainedRef reference = mReference.get(); |
||||
if (reference != null) { |
||||
reference.remove(); |
||||
} |
||||
if (delegate != null) { |
||||
delegate.run(); |
||||
} |
||||
} |
||||
} |
||||
|
||||
static class ChainedRef { |
||||
@Nullable |
||||
ChainedRef next; |
||||
@Nullable |
||||
ChainedRef prev; |
||||
@NonNull |
||||
final Runnable runnable; |
||||
@NonNull |
||||
final WeakRunnable wrapper; |
||||
|
||||
@NonNull |
||||
Lock lock; |
||||
|
||||
public ChainedRef(@NonNull Lock lock, @NonNull Runnable r) { |
||||
this.runnable = r; |
||||
this.lock = lock; |
||||
this.wrapper = new WeakRunnable(new WeakReference<>(r), new WeakReference<>(this)); |
||||
} |
||||
|
||||
public WeakRunnable remove() { |
||||
lock.lock(); |
||||
try { |
||||
if (prev != null) { |
||||
prev.next = next; |
||||
} |
||||
if (next != null) { |
||||
next.prev = prev; |
||||
} |
||||
prev = null; |
||||
next = null; |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
return wrapper; |
||||
} |
||||
|
||||
public void insertAfter(@NonNull ChainedRef candidate) { |
||||
lock.lock(); |
||||
try { |
||||
if (this.next != null) { |
||||
this.next.prev = candidate; |
||||
} |
||||
|
||||
candidate.next = this.next; |
||||
this.next = candidate; |
||||
candidate.prev = this; |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
} |
||||
|
||||
@Nullable |
||||
public WeakRunnable remove(Runnable obj) { |
||||
lock.lock(); |
||||
try { |
||||
ChainedRef curr = this.next; // Skipping head
|
||||
while (curr != null) { |
||||
if (curr.runnable == obj) { // We do comparison exactly how Handler does inside
|
||||
return curr.remove(); |
||||
} |
||||
curr = curr.next; |
||||
} |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
return null; |
||||
} |
||||
} |
||||
} |
Loading…
Reference in new issue