com.nostra13.universalimageloader.core.ImageLoaderEngine Maven / Gradle / Ivy
/*******************************************************************************
* 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.view.View;
import com.nostra13.universalimageloader.core.assist.FailReason;
import com.nostra13.universalimageloader.core.assist.FlushedInputStream;
import com.nostra13.universalimageloader.core.assist.ImageLoadingListener;
import com.nostra13.universalimageloader.core.imageaware.ImageAware;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.locks.ReentrantLock;
/**
* {@link ImageLoader} engine which responsible for {@linkplain LoadAndDisplayImageTask display task} execution.
*
* @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
* @since 1.7.1
*/
class ImageLoaderEngine {
final ImageLoaderConfiguration configuration;
private Executor taskExecutor;
private Executor taskExecutorForCachedImages;
private ExecutorService taskDistributor;
private final Map cacheKeysForImageAwares = Collections
.synchronizedMap(new HashMap());
private final Map uriLocks = new WeakHashMap();
private final AtomicBoolean paused = new AtomicBoolean(false);
private final AtomicBoolean networkDenied = new AtomicBoolean(false);
private final AtomicBoolean slowNetwork = new AtomicBoolean(false);
ImageLoaderEngine(ImageLoaderConfiguration configuration) {
this.configuration = configuration;
taskExecutor = configuration.taskExecutor;
taskExecutorForCachedImages = configuration.taskExecutorForCachedImages;
taskDistributor = Executors.newCachedThreadPool();
}
/** Submits task to execution pool */
void submit(final LoadAndDisplayImageTask task) {
taskDistributor.execute(new Runnable() {
@Override
public void run() {
boolean isImageCachedOnDisc = configuration.discCache.get(task.getLoadingUri()).exists();
initExecutorsIfNeed();
if (isImageCachedOnDisc) {
taskExecutorForCachedImages.execute(task);
} else {
taskExecutor.execute(task);
}
}
});
}
/** Submits task to execution pool */
void submit(ProcessAndDisplayImageTask task) {
initExecutorsIfNeed();
taskExecutorForCachedImages.execute(task);
}
private void initExecutorsIfNeed() {
if (!configuration.customExecutor && ((ExecutorService) taskExecutor).isShutdown()) {
taskExecutor = createTaskExecutor();
}
if (!configuration.customExecutorForCachedImages && ((ExecutorService) taskExecutorForCachedImages)
.isShutdown()) {
taskExecutorForCachedImages = createTaskExecutor();
}
}
private Executor createTaskExecutor() {
return DefaultConfigurationFactory
.createExecutor(configuration.threadPoolSize, configuration.threadPriority, configuration.tasksProcessingType);
}
/**
* Returns URI of image which is loading at this moment into passed
* {@link com.nostra13.universalimageloader.core.imageaware.ImageAware}
*/
String getLoadingUriForView(ImageAware imageAware) {
return cacheKeysForImageAwares.get(imageAware.getId());
}
/**
* Associates memoryCacheKey with imageAware. Then it helps to define image URI is loaded into
* View at exact moment.
*/
void prepareDisplayTaskFor(ImageAware imageAware, String memoryCacheKey) {
cacheKeysForImageAwares.put(imageAware.getId(), memoryCacheKey);
}
/**
* Cancels the task of loading and displaying image for incoming imageAware.
*
* @param imageAware {@link com.nostra13.universalimageloader.core.imageaware.ImageAware} for which display task
* will be cancelled
*/
void cancelDisplayTaskFor(ImageAware imageAware) {
cacheKeysForImageAwares.remove(imageAware.getId());
}
/**
* Denies or allows engine to download images from the network.
*
* If downloads are denied and if image isn't cached then
* {@link ImageLoadingListener#onLoadingFailed(String, View, FailReason)} callback will be fired with
* {@link FailReason.FailType#NETWORK_DENIED}
*
* @param denyNetworkDownloads pass true - to deny engine to download images from the network; false -
* to allow engine to download images from network.
*/
void denyNetworkDownloads(boolean denyNetworkDownloads) {
networkDenied.set(denyNetworkDownloads);
}
/**
* Sets option whether ImageLoader will use {@link FlushedInputStream} for network downloads to handle this known problem or not.
*
* @param handleSlowNetwork pass true - to use {@link FlushedInputStream} for network downloads; false
* - otherwise.
*/
void handleSlowNetwork(boolean handleSlowNetwork) {
slowNetwork.set(handleSlowNetwork);
}
/**
* Pauses engine. All new "load&display" tasks won't be executed until ImageLoader is {@link #resume() resumed}.
* Already running tasks are not paused.
*/
void pause() {
paused.set(true);
}
/** Resumes engine work. Paused "load&display" tasks will continue its work. */
void resume() {
synchronized (paused) {
paused.set(false);
paused.notifyAll();
}
}
/** Stops engine, cancels all running and scheduled display image tasks. Clears internal data. */
void stop() {
if (!configuration.customExecutor) {
((ExecutorService) taskExecutor).shutdownNow();
}
if (!configuration.customExecutorForCachedImages) {
((ExecutorService) taskExecutorForCachedImages).shutdownNow();
}
cacheKeysForImageAwares.clear();
uriLocks.clear();
}
ReentrantLock getLockForUri(String uri) {
ReentrantLock lock = uriLocks.get(uri);
if (lock == null) {
lock = new ReentrantLock();
uriLocks.put(uri, lock);
}
return lock;
}
AtomicBoolean getPause() {
return paused;
}
boolean isNetworkDenied() {
return networkDenied.get();
}
boolean isSlowNetwork() {
return slowNetwork.get();
}
}