Merge "Fix the race condition that cause windows cache stale" (224c55d4) · Commits · e / os / android_frameworks_base

core/java/android/view/accessibility/AccessibilityCache.java

+16 −1

Original line number	Original line	Diff line number	Diff line
	@@ -20,6 +20,7 @@ package android.view.accessibility;
	import static android.view.accessibility.AccessibilityNodeInfo.FOCUS_ACCESSIBILITY;		import static android.view.accessibility.AccessibilityNodeInfo.FOCUS_ACCESSIBILITY;

	import android.os.Build;		import android.os.Build;
			import android.os.SystemClock;
	import android.util.ArraySet;		import android.util.ArraySet;
	import android.util.Log;		import android.util.Log;
	import android.util.LongArray;		import android.util.LongArray;
	@@ -71,6 +72,11 @@ public class AccessibilityCache {

	private long mAccessibilityFocus = AccessibilityNodeInfo.UNDEFINED_ITEM_ID;		private long mAccessibilityFocus = AccessibilityNodeInfo.UNDEFINED_ITEM_ID;
	private long mInputFocus = AccessibilityNodeInfo.UNDEFINED_ITEM_ID;		private long mInputFocus = AccessibilityNodeInfo.UNDEFINED_ITEM_ID;
			/**
			* The event time of the {@link AccessibilityEvent} which presents the populated windows cache
			* before it is stale.
			*/
			private long mValidWindowCacheTimeStamp = 0;

	private int mAccessibilityFocusedWindow = AccessibilityWindowInfo.UNDEFINED_WINDOW_ID;		private int mAccessibilityFocusedWindow = AccessibilityWindowInfo.UNDEFINED_WINDOW_ID;
	private int mInputFocusWindow = AccessibilityWindowInfo.UNDEFINED_WINDOW_ID;		private int mInputFocusWindow = AccessibilityWindowInfo.UNDEFINED_WINDOW_ID;
	@@ -97,13 +103,20 @@ public class AccessibilityCache {
	* The key of SparseArray is display ID.		* The key of SparseArray is display ID.
	*		*
	* @param windowsOnAllDisplays The accessibility windows of all displays.		* @param windowsOnAllDisplays The accessibility windows of all displays.
			* @param populationTimeStamp The timestamp from {@link SystemClock#uptimeMillis()} when the
			* client requests the data.
	*/		*/
	public void setWindowsOnAllDisplays(		public void setWindowsOnAllDisplays(
	SparseArray<List<AccessibilityWindowInfo>> windowsOnAllDisplays) {		SparseArray<List<AccessibilityWindowInfo>> windowsOnAllDisplays,
			long populationTimeStamp) {
	synchronized (mLock) {		synchronized (mLock) {
	if (DEBUG) {		if (DEBUG) {
	Log.i(LOG_TAG, "Set windows");		Log.i(LOG_TAG, "Set windows");
	}		}
			if (mValidWindowCacheTimeStamp > populationTimeStamp) {
			// Discard the windows because it might be stale.
			return;
			}
	clearWindowCacheLocked();		clearWindowCacheLocked();
	if (windowsOnAllDisplays == null) {		if (windowsOnAllDisplays == null) {
	return;		return;
	@@ -224,6 +237,7 @@ public class AccessibilityCache {
	} break;		} break;

	case AccessibilityEvent.TYPE_WINDOWS_CHANGED:		case AccessibilityEvent.TYPE_WINDOWS_CHANGED:
			mValidWindowCacheTimeStamp = event.getEventTime();
	if (event.getWindowChanges()		if (event.getWindowChanges()
	== AccessibilityEvent.WINDOWS_CHANGE_ACCESSIBILITY_FOCUSED) {		== AccessibilityEvent.WINDOWS_CHANGE_ACCESSIBILITY_FOCUSED) {
	// Don't need to clear all cache. Unless the changes are related to		// Don't need to clear all cache. Unless the changes are related to
	@@ -232,6 +246,7 @@ public class AccessibilityCache {
	break;		break;
	}		}
	case AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED: {		case AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED: {
			mValidWindowCacheTimeStamp = event.getEventTime();
	clear();		clear();
	} break;		} break;
	}		}

core/java/android/view/accessibility/AccessibilityInteractionClient.java

+3 −1

Original line number	Original line	Diff line number	Diff line
	@@ -435,8 +435,10 @@ public final class AccessibilityInteractionClient
	}		}
	}		}

			long populationTimeStamp;
	final long identityToken = Binder.clearCallingIdentity();		final long identityToken = Binder.clearCallingIdentity();
	try {		try {
			populationTimeStamp = SystemClock.uptimeMillis();
	windows = connection.getWindows();		windows = connection.getWindows();
	} finally {		} finally {
	Binder.restoreCallingIdentity(identityToken);		Binder.restoreCallingIdentity(identityToken);
	@@ -446,7 +448,7 @@ public final class AccessibilityInteractionClient
	}		}
	if (windows != null) {		if (windows != null) {
	if (sAccessibilityCache != null) {		if (sAccessibilityCache != null) {
	sAccessibilityCache.setWindowsOnAllDisplays(windows);		sAccessibilityCache.setWindowsOnAllDisplays(windows, populationTimeStamp);
	}		}
	return windows;		return windows;
	}		}

core/tests/coretests/src/android/view/accessibility/AccessibilityCacheTest.java

+49 −2

Original line number	Original line	Diff line number	Diff line
	@@ -35,6 +35,7 @@ import static org.mockito.Mockito.never;
	import static org.mockito.Mockito.verify;		import static org.mockito.Mockito.verify;
	import static org.mockito.Mockito.when;		import static org.mockito.Mockito.when;

			import android.os.SystemClock;
	import android.util.SparseArray;		import android.util.SparseArray;
	import android.view.Display;		import android.view.Display;
	import android.view.View;		import android.view.View;
	@@ -299,7 +300,8 @@ public class AccessibilityCacheTest {
	SparseArray<List<AccessibilityWindowInfo>> allWindows = new SparseArray<>();		SparseArray<List<AccessibilityWindowInfo>> allWindows = new SparseArray<>();
	allWindows.put(Display.DEFAULT_DISPLAY, windowsIn1);		allWindows.put(Display.DEFAULT_DISPLAY, windowsIn1);
	allWindows.put(SECONDARY_DISPLAY_ID, windowsIn2);		allWindows.put(SECONDARY_DISPLAY_ID, windowsIn2);
	mAccessibilityCache.setWindowsOnAllDisplays(allWindows);		final long populationTimeStamp = SystemClock.uptimeMillis();
			mAccessibilityCache.setWindowsOnAllDisplays(allWindows, populationTimeStamp);
	// Gets windows at default display.		// Gets windows at default display.
	windowsOut1 = getWindowsByDisplay(Display.DEFAULT_DISPLAY);		windowsOut1 = getWindowsByDisplay(Display.DEFAULT_DISPLAY);
	window1Out = mAccessibilityCache.getWindow(WINDOW_ID_1);		window1Out = mAccessibilityCache.getWindow(WINDOW_ID_1);
	@@ -338,6 +340,46 @@ public class AccessibilityCacheTest {
	}		}
	}		}

			@Test
			public void setInvalidWindowsAfterWindowsChangedEvent_notInCache() {
			final AccessibilityEvent event = new AccessibilityEvent(
			AccessibilityEvent.TYPE_WINDOWS_CHANGED);
			final long eventTime = 1000L;
			event.setEventTime(eventTime);
			mAccessibilityCache.onAccessibilityEvent(event);

			final AccessibilityWindowInfo windowInfo1 = obtainAccessibilityWindowInfo(WINDOW_ID_1,
			SPECIFIC_WINDOW_LAYER);
			List<AccessibilityWindowInfo> windowsIn = Arrays.asList(windowInfo1);
			setWindowsByDisplay(Display.DEFAULT_DISPLAY, windowsIn, eventTime - 10);

			try {
			assertNull(getWindowsByDisplay(Display.DEFAULT_DISPLAY));
			} finally {
			windowInfo1.recycle();
			}
			}

			@Test
			public void setInvalidWindowsAfterStateChangedEvent_notInCache() {
			final AccessibilityEvent event = new AccessibilityEvent(
			AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED);
			final long eventTime = 1000L;
			event.setEventTime(eventTime);
			mAccessibilityCache.onAccessibilityEvent(event);

			final AccessibilityWindowInfo windowInfo1 = obtainAccessibilityWindowInfo(WINDOW_ID_1,
			SPECIFIC_WINDOW_LAYER);
			List<AccessibilityWindowInfo> windowsIn = Arrays.asList(windowInfo1);
			setWindowsByDisplay(Display.DEFAULT_DISPLAY, windowsIn, eventTime - 10);

			try {
			assertNull(getWindowsByDisplay(Display.DEFAULT_DISPLAY));
			} finally {
			windowInfo1.recycle();
			}
			}

	@Test		@Test
	public void addWindowThenStateChangedEvent_noLongerInCache() {		public void addWindowThenStateChangedEvent_noLongerInCache() {
	putWindowWithWindowIdAndDisplayIdInCache(WINDOW_ID_1, Display.DEFAULT_DISPLAY,		putWindowWithWindowIdAndDisplayIdInCache(WINDOW_ID_1, Display.DEFAULT_DISPLAY,
	@@ -1063,9 +1105,14 @@ public class AccessibilityCacheTest {
	}		}

	private void setWindowsByDisplay(int displayId, List<AccessibilityWindowInfo> windows) {		private void setWindowsByDisplay(int displayId, List<AccessibilityWindowInfo> windows) {
			setWindowsByDisplay(displayId, windows, SystemClock.uptimeMillis());
			}

			private void setWindowsByDisplay(int displayId, List<AccessibilityWindowInfo> windows,
			long populationTimeStamp) {
	SparseArray<List<AccessibilityWindowInfo>> allWindows = new SparseArray<>();		SparseArray<List<AccessibilityWindowInfo>> allWindows = new SparseArray<>();
	allWindows.put(displayId, windows);		allWindows.put(displayId, windows);
	mAccessibilityCache.setWindowsOnAllDisplays(allWindows);		mAccessibilityCache.setWindowsOnAllDisplays(allWindows, populationTimeStamp);
	}		}

	private List<AccessibilityWindowInfo> getWindowsByDisplay(int displayId) {		private List<AccessibilityWindowInfo> getWindowsByDisplay(int displayId) {