/*******************************************************************************
* Copyright 2011-2013 Sergey Tarasevich
*
* 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.nostra13.universalimageloader.core;
import android.graphics.Bitmap;
import android.os.Handler;
import com.nostra13.universalimageloader.core.assist.FailReason;
import com.nostra13.universalimageloader.core.assist.FailReason.FailType;
import com.nostra13.universalimageloader.core.assist.ImageScaleType;
import com.nostra13.universalimageloader.core.assist.ImageSize;
import com.nostra13.universalimageloader.core.assist.LoadedFrom;
import com.nostra13.universalimageloader.core.assist.ViewScaleType;
import com.nostra13.universalimageloader.core.decode.ImageDecoder;
import com.nostra13.universalimageloader.core.decode.ImageDecodingInfo;
import com.nostra13.universalimageloader.core.download.ImageDownloader;
import com.nostra13.universalimageloader.core.download.ImageDownloader.Scheme;
import com.nostra13.universalimageloader.core.imageaware.ImageAware;
import com.nostra13.universalimageloader.core.listener.ImageLoadingListener;
import com.nostra13.universalimageloader.core.listener.ImageLoadingProgressListener;
import com.nostra13.universalimageloader.utils.IoUtils;
import com.nostra13.universalimageloader.utils.L;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.locks.ReentrantLock;
/**
* Presents load'n'display image task. Used to load image from Internet or file system, decode it to {@link Bitmap}, and
* display it in {@link com.nostra13.universalimageloader.core.imageaware.ImageAware} using {@link DisplayBitmapTask}.
*
* @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
* @see ImageLoaderConfiguration
* @see ImageLoadingInfo
* @since 1.3.1
*/
final class LoadAndDisplayImageTask implements Runnable, IoUtils.CopyListener {
private static final String LOG_WAITING_FOR_RESUME = "ImageLoader is paused. Waiting... [%s]";
private static final String LOG_RESUME_AFTER_PAUSE = ".. Resume loading [%s]";
private static final String LOG_DELAY_BEFORE_LOADING = "Delay %d ms before loading... [%s]";
private static final String LOG_START_DISPLAY_IMAGE_TASK = "Start display image task [%s]";
private static final String LOG_WAITING_FOR_IMAGE_LOADED = "Image already is loading. Waiting... [%s]";
private static final String LOG_GET_IMAGE_FROM_MEMORY_CACHE_AFTER_WAITING = "...Get cached bitmap from memory after waiting. [%s]";
private static final String LOG_LOAD_IMAGE_FROM_NETWORK = "Load image from network [%s]";
private static final String LOG_LOAD_IMAGE_FROM_DISK_CACHE = "Load image from disk cache [%s]";
private static final String LOG_RESIZE_CACHED_IMAGE_FILE = "Resize image in disk cache [%s]";
private static final String LOG_PREPROCESS_IMAGE = "PreProcess image before caching in memory [%s]";
private static final String LOG_POSTPROCESS_IMAGE = "PostProcess image before displaying [%s]";
private static final String LOG_CACHE_IMAGE_IN_MEMORY = "Cache image in memory [%s]";
private static final String LOG_CACHE_IMAGE_ON_DISK = "Cache image on disk [%s]";
private static final String LOG_PROCESS_IMAGE_BEFORE_CACHE_ON_DISK = "Process image before cache on disk [%s]";
private static final String LOG_TASK_CANCELLED_IMAGEAWARE_REUSED = "ImageAware is reused for another image. Task is cancelled. [%s]";
private static final String LOG_TASK_CANCELLED_IMAGEAWARE_COLLECTED = "ImageAware was collected by GC. Task is cancelled. [%s]";
private static final String LOG_TASK_INTERRUPTED = "Task was interrupted [%s]";
private static final String ERROR_PRE_PROCESSOR_NULL = "Pre-processor returned null [%s]";
private static final String ERROR_POST_PROCESSOR_NULL = "Post-processor returned null [%s]";
private static final String ERROR_PROCESSOR_FOR_DISK_CACHE_NULL = "Bitmap processor for disk cache returned null [%s]";
private final ImageLoaderEngine engine;
private final ImageLoadingInfo imageLoadingInfo;
private final Handler handler;
// Helper references
private final ImageLoaderConfiguration configuration;
private final ImageDownloader downloader;
private final ImageDownloader networkDeniedDownloader;
private final ImageDownloader slowNetworkDownloader;
private final ImageDecoder decoder;
final String uri;
private final String memoryCacheKey;
final ImageAware imageAware;
private final ImageSize targetSize;
final DisplayImageOptions options;
final ImageLoadingListener listener;
final ImageLoadingProgressListener progressListener;
private final boolean syncLoading;
// State vars
private LoadedFrom loadedFrom = LoadedFrom.NETWORK;
public LoadAndDisplayImageTask(ImageLoaderEngine engine, ImageLoadingInfo imageLoadingInfo, Handler handler) {
this.engine = engine;
this.imageLoadingInfo = imageLoadingInfo;
this.handler = handler;
configuration = engine.configuration;
downloader = configuration.downloader;
networkDeniedDownloader = configuration.networkDeniedDownloader;
slowNetworkDownloader = configuration.slowNetworkDownloader;
decoder = configuration.decoder;
uri = imageLoadingInfo.uri;
memoryCacheKey = imageLoadingInfo.memoryCacheKey;
imageAware = imageLoadingInfo.imageAware;
targetSize = imageLoadingInfo.targetSize;
options = imageLoadingInfo.options;
listener = imageLoadingInfo.listener;
progressListener = imageLoadingInfo.progressListener;
syncLoading = options.isSyncLoading();
}
@Override
public void run() {
if (waitIfPaused()) return;
if (delayIfNeed()) return;
ReentrantLock loadFromUriLock = imageLoadingInfo.loadFromUriLock;
L.d(LOG_START_DISPLAY_IMAGE_TASK, memoryCacheKey);
if (loadFromUriLock.isLocked()) {
L.d(LOG_WAITING_FOR_IMAGE_LOADED, memoryCacheKey);
}
loadFromUriLock.lock();
Bitmap bmp;
try {
checkTaskNotActual();
bmp = configuration.memoryCache.get(memoryCacheKey);
if (bmp == null || bmp.isRecycled()) {
bmp = tryLoadBitmap();
if (bmp == null) return; // listener callback already was fired
checkTaskNotActual();
checkTaskInterrupted();
if (options.shouldPreProcess()) {
L.d(LOG_PREPROCESS_IMAGE, memoryCacheKey);
bmp = options.getPreProcessor().process(bmp);
if (bmp == null) {
L.e(ERROR_PRE_PROCESSOR_NULL, memoryCacheKey);
}
}
if (bmp != null && options.isCacheInMemory()) {
L.d(LOG_CACHE_IMAGE_IN_MEMORY, memoryCacheKey);
configuration.memoryCache.put(memoryCacheKey, bmp);
}
} else {
loadedFrom = LoadedFrom.MEMORY_CACHE;
L.d(LOG_GET_IMAGE_FROM_MEMORY_CACHE_AFTER_WAITING, memoryCacheKey);
}
if (bmp != null && options.shouldPostProcess()) {
L.d(LOG_POSTPROCESS_IMAGE, memoryCacheKey);
bmp = options.getPostProcessor().process(bmp);
if (bmp == null) {
L.e(ERROR_POST_PROCESSOR_NULL, memoryCacheKey);
}
}
checkTaskNotActual();
checkTaskInterrupted();
} catch (TaskCancelledException e) {
fireCancelEvent();
return;
} finally {
loadFromUriLock.unlock();
}
DisplayBitmapTask displayBitmapTask = new DisplayBitmapTask(bmp, imageLoadingInfo, engine, loadedFrom);
runTask(displayBitmapTask, syncLoading, handler, engine);
}
/** @return <b>true</b> - if task should be interrupted; <b>false</b> - otherwise */
private boolean waitIfPaused() {
AtomicBoolean pause = engine.getPause();
if (pause.get()) {
synchronized (engine.getPauseLock()) {
if (pause.get()) {
L.d(LOG_WAITING_FOR_RESUME, memoryCacheKey);
try {
engine.getPauseLock().wait();
} catch (InterruptedException e) {
L.e(LOG_TASK_INTERRUPTED, memoryCacheKey);
return true;
}
L.d(LOG_RESUME_AFTER_PAUSE, memoryCacheKey);
}
}
}
return isTaskNotActual();
}
/** @return <b>true</b> - if task should be interrupted; <b>false</b> - otherwise */
private boolean delayIfNeed() {
if (options.shouldDelayBeforeLoading()) {
L.d(LOG_DELAY_BEFORE_LOADING, options.getDelayBeforeLoading(), memoryCacheKey);
try {
Thread.sleep(options.getDelayBeforeLoading());
} catch (InterruptedException e) {
L.e(LOG_TASK_INTERRUPTED, memoryCacheKey);
return true;
}
return isTaskNotActual();
}
return false;
}
private Bitmap tryLoadBitmap() throws TaskCancelledException {
Bitmap bitmap = null;
try {
File imageFile = configuration.diskCache.get(uri);
if (imageFile != null && imageFile.exists()) {
L.d(LOG_LOAD_IMAGE_FROM_DISK_CACHE, memoryCacheKey);
loadedFrom = LoadedFrom.DISC_CACHE;
checkTaskNotActual();
bitmap = decodeImage(Scheme.FILE.wrap(imageFile.getAbsolutePath()));
}
if (bitmap == null || bitmap.getWidth() <= 0 || bitmap.getHeight() <= 0) {
L.d(LOG_LOAD_IMAGE_FROM_NETWORK, memoryCacheKey);
loadedFrom = LoadedFrom.NETWORK;
String imageUriForDecoding = uri;
if (options.isCacheOnDisk() && tryCacheImageOnDisk()) {
imageFile = configuration.diskCache.get(uri);
if (imageFile != null) {
imageUriForDecoding = Scheme.FILE.wrap(imageFile.getAbsolutePath());
}
}
checkTaskNotActual();
bitmap = decodeImage(imageUriForDecoding);
if (bitmap == null || bitmap.getWidth() <= 0 || bitmap.getHeight() <= 0) {
fireFailEvent(FailType.DECODING_ERROR, null);
}
}
} catch (IllegalStateException e) {
fireFailEvent(FailType.NETWORK_DENIED, null);
} catch (TaskCancelledException e) {
throw e;
} catch (IOException e) {
L.e(e);
fireFailEvent(FailType.IO_ERROR, e);
} catch (OutOfMemoryError e) {
L.e(e);
fireFailEvent(FailType.OUT_OF_MEMORY, e);
} catch (Throwable e) {
L.e(e);
fireFailEvent(FailType.UNKNOWN, e);
}
return bitmap;
}
private Bitmap decodeImage(String imageUri) throws IOException {
ViewScaleType viewScaleType = imageAware.getScaleType();
ImageDecodingInfo decodingInfo = new ImageDecodingInfo(memoryCacheKey, imageUri, uri, targetSize, viewScaleType,
getDownloader(), options);
return decoder.decode(decodingInfo);
}
/** @return <b>true</b> - if image was downloaded successfully; <b>false</b> - otherwise */
private boolean tryCacheImageOnDisk() throws TaskCancelledException {
L.d(LOG_CACHE_IMAGE_ON_DISK, memoryCacheKey);
boolean loaded;
try {
loaded = downloadImage();
if (loaded) {
int width = configuration.maxImageWidthForDiskCache;
int height = configuration.maxImageHeightForDiskCache;
if (width > 0 || height > 0) {
L.d(LOG_RESIZE_CACHED_IMAGE_FILE, memoryCacheKey);
resizeAndSaveImage(width, height); // TODO : process boolean result
}
}
} catch (IOException e) {
L.e(e);
loaded = false;
}
return loaded;
}
private boolean downloadImage() throws IOException {
InputStream is = getDownloader().getStream(uri, options.getExtraForDownloader());
return configuration.diskCache.save(uri, is, this);
}
/** Decodes image file into Bitmap, resize it and save it back */
private boolean resizeAndSaveImage(int maxWidth, int maxHeight) throws IOException {
// Decode image file, compress and re-save it
boolean saved = false;
File targetFile = configuration.diskCache.get(uri);
if (targetFile != null && targetFile.exists()) {
ImageSize targetImageSize = new ImageSize(maxWidth, maxHeight);
DisplayImageOptions specialOptions = new DisplayImageOptions.Builder().cloneFrom(options)
.imageScaleType(ImageScaleType.IN_SAMPLE_INT).build();
ImageDecodingInfo decodingInfo = new ImageDecodingInfo(memoryCacheKey,
Scheme.FILE.wrap(targetFile.getAbsolutePath()), uri, targetImageSize, ViewScaleType.FIT_INSIDE,
getDownloader(), specialOptions);
Bitmap bmp = decoder.decode(decodingInfo);
if (bmp != null && configuration.processorForDiskCache != null) {
L.d(LOG_PROCESS_IMAGE_BEFORE_CACHE_ON_DISK, memoryCacheKey);
bmp = configuration.processorForDiskCache.process(bmp);
if (bmp == null) {
L.e(ERROR_PROCESSOR_FOR_DISK_CACHE_NULL, memoryCacheKey);
}
}
if (bmp != null) {
saved = configuration.diskCache.save(uri, bmp);
bmp.recycle();
}
}
return saved;
}
@Override
public boolean onBytesCopied(int current, int total) {
return syncLoading || fireProgressEvent(current, total);
}
/** @return <b>true</b> - if loading should be continued; <b>false</b> - if loading should be interrupted */
private boolean fireProgressEvent(final int current, final int total) {
if (isTaskInterrupted() || isTaskNotActual()) return false;
if (progressListener != null) {
Runnable r = new Runnable() {
@Override
public void run() {
progressListener.onProgressUpdate(uri, imageAware.getWrappedView(), current, total);
}
};
runTask(r, false, handler, engine);
}
return true;
}
private void fireFailEvent(final FailType failType, final Throwable failCause) {
if (syncLoading || isTaskInterrupted() || isTaskNotActual()) return;
Runnable r = new Runnable() {
@Override
public void run() {
if (options.shouldShowImageOnFail()) {
imageAware.setImageDrawable(options.getImageOnFail(configuration.resources));
}
listener.onLoadingFailed(uri, imageAware.getWrappedView(), new FailReason(failType, failCause));
}
};
runTask(r, false, handler, engine);
}
private void fireCancelEvent() {
if (syncLoading || isTaskInterrupted()) return;
Runnable r = new Runnable() {
@Override
public void run() {
listener.onLoadingCancelled(uri, imageAware.getWrappedView());
}
};
runTask(r, false, handler, engine);
}
private ImageDownloader getDownloader() {
ImageDownloader d;
if (engine.isNetworkDenied()) {
d = networkDeniedDownloader;
} else if (engine.isSlowNetwork()) {
d = slowNetworkDownloader;
} else {
d = downloader;
}
return d;
}
/**
* @throws TaskCancelledException if task is not actual (target ImageAware is collected by GC or the image URI of
* this task doesn't match to image URI which is actual for current ImageAware at
* this moment)
*/
private void checkTaskNotActual() throws TaskCancelledException {
checkViewCollected();
checkViewReused();
}
/**
* @return <b>true</b> - if task is not actual (target ImageAware is collected by GC or the image URI of this task
* doesn't match to image URI which is actual for current ImageAware at this moment)); <b>false</b> - otherwise
*/
private boolean isTaskNotActual() {
return isViewCollected() || isViewReused();
}
/** @throws TaskCancelledException if target ImageAware is collected */
private void checkViewCollected() throws TaskCancelledException {
if (isViewCollected()) {
throw new TaskCancelledException();
}
}
/** @return <b>true</b> - if target ImageAware is collected by GC; <b>false</b> - otherwise */
private boolean isViewCollected() {
if (imageAware.isCollected()) {
L.d(LOG_TASK_CANCELLED_IMAGEAWARE_COLLECTED, memoryCacheKey);
return true;
}
return false;
}
/** @throws TaskCancelledException if target ImageAware is collected by GC */
private void checkViewReused() throws TaskCancelledException {
if (isViewReused()) {
throw new TaskCancelledException();
}
}
/** @return <b>true</b> - if current ImageAware is reused for displaying another image; <b>false</b> - otherwise */
private boolean isViewReused() {
String currentCacheKey = engine.getLoadingUriForView(imageAware);
// Check whether memory cache key (image URI) for current ImageAware is actual.
// If ImageAware is reused for another task then current task should be cancelled.
boolean imageAwareWasReused = !memoryCacheKey.equals(currentCacheKey);
if (imageAwareWasReused) {
L.d(LOG_TASK_CANCELLED_IMAGEAWARE_REUSED, memoryCacheKey);
return true;
}
return false;
}
/** @throws TaskCancelledException if current task was interrupted */
private void checkTaskInterrupted() throws TaskCancelledException {
if (isTaskInterrupted()) {
throw new TaskCancelledException();
}
}
/** @return <b>true</b> - if current task was interrupted; <b>false</b> - otherwise */
private boolean isTaskInterrupted() {
if (Thread.interrupted()) {
L.d(LOG_TASK_INTERRUPTED, memoryCacheKey);
return true;
}
return false;
}
String getLoadingUri() {
return uri;
}
static void runTask(Runnable r, boolean sync, Handler handler, ImageLoaderEngine engine) {
if (sync) {
r.run();
} else if (handler == null) {
engine.fireCallback(r);
} else {
handler.post(r);
}
}
/**
* Exceptions for case when task is cancelled (thread is interrupted, image view is reused for another task, view is
* collected by GC).
*
* @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
* @since 1.9.1
*/
class TaskCancelledException extends Exception {
}
}