Merge "Extract task list operations from MTP DocumentLoader to the internal task list class." (831c5a1e) · Commits · e / os / android_frameworks_base

packages/MtpDocumentsProvider/src/com/android/mtp/DocumentLoader.java

+55 −39

Original line number	Diff line number	Diff line
		@@ -30,6 +30,11 @@ import java.util.Arrays;
		import java.util.Date;
		import java.util.LinkedList;

		/**
		* Loader for MTP document.
		* At the first request, the loader returns only first NUM_INITIAL_ENTRIES. Then it launches
		* background thread to load the rest documents and caches its result for next requests.
		*/
		class DocumentLoader {
		static final int NUM_INITIAL_ENTRIES = 10;
		static final int NUM_LOADING_ENTRIES = 20;
		@@ -37,7 +42,7 @@ class DocumentLoader {

		private final MtpManager mMtpManager;
		private final ContentResolver mResolver;
		private final LinkedList<LoaderTask> mTasks = new LinkedList<LoaderTask>();
		private final TaskList mTaskList = new TaskList();
		private boolean mHasBackgroundThread = false;

		DocumentLoader(MtpManager mtpManager, ContentResolver resolver) {
		@@ -56,7 +61,7 @@ class DocumentLoader {

		synchronized Cursor queryChildDocuments(String[] columnNames, Identifier parent)
		throws IOException {
		LoaderTask task = findTask(parent);
		LoaderTask task = mTaskList.findTask(parent);
		if (task == null) {
		int parentHandle = parent.mObjectHandle;
		// Need to pass the special value MtpManager.OBJECT_HANDLE_ROOT_CHILDREN to
		@@ -70,11 +75,12 @@ class DocumentLoader {
		mMtpManager,
		parent.mDeviceId,
		task.getUnloadedObjectHandles(NUM_INITIAL_ENTRIES)));
		} else {
		// Once remove the existing task in order to add it to the head of the list.
		mTaskList.remove(task);
		}

		// Move this task to the head of the list to prioritize it.
		mTasks.remove(task);
		mTasks.addFirst(task);
		mTaskList.addFirst(task);
		if (!task.completed() && !mHasBackgroundThread) {
		mHasBackgroundThread = true;
		new BackgroundLoaderThread().start();
		@@ -84,41 +90,11 @@ class DocumentLoader {
		}

		synchronized void clearCache(int deviceId) {
		int i = 0;
		while (i < mTasks.size()) {
		if (mTasks.get(i).mIdentifier.mDeviceId == deviceId) {
		mTasks.remove(i);
		} else {
		i++;
		}
		}
		mTaskList.clearTaskForDevice(deviceId);
		}

		synchronized void clearCache() {
		int i = 0;
		while (i < mTasks.size()) {
		if (mTasks.get(i).completed()) {
		mTasks.remove(i);
		} else {
		i++;
		}
		}
		}

		private LoaderTask findTask(Identifier parent) {
		for (int i = 0; i < mTasks.size(); i++) {
		if (mTasks.get(i).mIdentifier.equals(parent))
		return mTasks.get(i);
		}
		return null;
		}

		private LoaderTask findUncompletedTask() {
		for (int i = 0; i < mTasks.size(); i++) {
		if (!mTasks.get(i).completed())
		return mTasks.get(i);
		}
		return null;
		mTaskList.clearCompletedTask();
		}

		private class BackgroundLoaderThread extends Thread {
		@@ -130,7 +106,7 @@ class DocumentLoader {
		int deviceId;
		int[] handles;
		synchronized (DocumentLoader.this) {
		task = findUncompletedTask();
		task = mTaskList.findRunningTask();
		if (task == null) {
		mHasBackgroundThread = false;
		return;
		@@ -156,10 +132,50 @@ class DocumentLoader {
		task.notify(mResolver);
		}
		} else {
		mTasks.remove(task);
		mTaskList.remove(task);
		}
		}
		}
		}
		}

		private static class TaskList extends LinkedList<LoaderTask> {
		LoaderTask findTask(Identifier parent) {
		for (int i = 0; i < size(); i++) {
		if (get(i).mIdentifier.equals(parent))
		return get(i);
		}
		return null;
		}

		LoaderTask findRunningTask() {
		for (int i = 0; i < size(); i++) {
		if (!get(i).completed())
		return get(i);
		}
		return null;
		}

		void clearTaskForDevice(int deviceId) {
		int i = 0;
		while (i < size()) {
		if (get(i).mIdentifier.mDeviceId == deviceId) {
		remove(i);
		} else {
		i++;
		}
		}
		}

		void clearCompletedTask() {
		int i = 0;
		while (i < size()) {
		if (get(i).completed()) {
		remove(i);
		} else {
		i++;
		}
		}
		}
		}