Java tutorial
/* * Copyright (C) 2012 The Android Open Source Project * * 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.itsherpa.andg.imageloader; import glas.bbsystem.BuildConfig; import java.io.BufferedInputStream; import java.io.BufferedOutputStream; import java.io.File; import java.io.FileDescriptor; import java.io.FileInputStream; import java.io.IOException; import java.io.OutputStream; import java.net.HttpURLConnection; import java.net.URL; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.HttpStatus; import org.apache.http.client.methods.HttpGet; import android.content.Context; import android.graphics.Bitmap; import android.media.ThumbnailUtils; import android.net.ConnectivityManager; import android.net.NetworkInfo; import android.net.http.AndroidHttpClient; import android.os.Build; import android.provider.MediaStore.Video.Thumbnails; import android.text.TextUtils; import com.itsherpa.andg.connection.request.CircleImageRequest; import com.itsherpa.andg.connection.request.ImageRequest; import com.itsherpa.andg.connection.request.ImageRequestWithSize; import com.itsherpa.andg.connection.request.PhotoThumbRequest; import com.itsherpa.andg.connection.request.VideoThumbRequest; import com.itsherpa.andg.util.LogUtils; import com.itsherpa.andg.util.Utility; /** * A simple subclass of {@link ImageResizer} that fetches and resizes images * fetched from a URL. */ public class ImageFetcher extends ImageResizer { private static final String TAG = "ImageFetcher"; private static final int HTTP_CACHE_SIZE = 50 * 1024 * 1024; // 50MB private static final String HTTP_CACHE_DIR = "http"; private static final int IO_BUFFER_SIZE = 8 * 1024; private DiskLruCache mHttpDiskCache; private File mHttpCacheDir; private boolean mHttpDiskCacheStarting = true; private final Object mHttpDiskCacheLock = new Object(); private static final int DISK_CACHE_INDEX = 0; public static final String AVATAR_CACHE_DIR = "avatar"; public static final String LARGE_CACHE_DIR = "large"; /** * Initialize providing a target image width and height for the processing * images. * * @param context * @param imageWidth * @param imageHeight */ public ImageFetcher(Context context) { super(context); init(context); } private void init(Context context) { checkConnection(context); mHttpCacheDir = ImageCache.getDiskCacheDir(context, HTTP_CACHE_DIR); } @Override protected void initDiskCacheInternal() { super.initDiskCacheInternal(); initHttpDiskCache(); } private void initHttpDiskCache() { if (!mHttpCacheDir.exists()) { mHttpCacheDir.mkdirs(); } synchronized (mHttpDiskCacheLock) { if (ImageCache.getUsableSpace(mHttpCacheDir) > HTTP_CACHE_SIZE) { try { mHttpDiskCache = DiskLruCache.open(mHttpCacheDir, 1, 1, HTTP_CACHE_SIZE); if (BuildConfig.DEBUG) { LogUtils.d(TAG, "HTTP cache initialized"); } } catch (IOException e) { mHttpDiskCache = null; } } mHttpDiskCacheStarting = false; mHttpDiskCacheLock.notifyAll(); } } @Override protected void clearCacheInternal() { super.clearCacheInternal(); synchronized (mHttpDiskCacheLock) { if (mHttpDiskCache != null && !mHttpDiskCache.isClosed()) { try { mHttpDiskCache.delete(); if (BuildConfig.DEBUG) { LogUtils.d(TAG, "HTTP cache cleared"); } } catch (IOException e) { LogUtils.e(TAG, "clearCacheInternal - " + e); } mHttpDiskCache = null; mHttpDiskCacheStarting = true; initHttpDiskCache(); } } } @Override protected void flushCacheInternal() { super.flushCacheInternal(); synchronized (mHttpDiskCacheLock) { if (mHttpDiskCache != null) { try { mHttpDiskCache.flush(); if (BuildConfig.DEBUG) { LogUtils.d(TAG, "HTTP cache flushed"); } } catch (IOException e) { LogUtils.e(TAG, "flush - " + e); } } } } @Override protected void closeCacheInternal() { super.closeCacheInternal(); synchronized (mHttpDiskCacheLock) { if (mHttpDiskCache != null) { try { if (!mHttpDiskCache.isClosed()) { mHttpDiskCache.close(); mHttpDiskCache = null; if (BuildConfig.DEBUG) { LogUtils.d(TAG, "HTTP cache closed"); } } } catch (IOException e) { LogUtils.e(TAG, "closeCacheInternal - " + e); } } } } /** * Simple network connection check. * * @param context */ private void checkConnection(Context context) { final ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); final NetworkInfo networkInfo = cm.getActiveNetworkInfo(); if (networkInfo == null || !networkInfo.isConnectedOrConnecting()) { LogUtils.e(TAG, "checkConnection - no connection found"); } } /** * The main process method, which will be called by the ImageWorker in the * AsyncTask background thread. * * @param data * The data to load the bitmap, in this case, a regular http URL * @return The downloaded and resized bitmap */ private Bitmap processBitmap(String data, int width, int height, String urlCache) { // if (BuildConfig.DEBUG) { // LogUtils.d(TAG, "processBitmap - " + data); // } final String key = ImageCache.hashKeyForDisk(urlCache); FileDescriptor fileDescriptor = null; FileInputStream fileInputStream = null; DiskLruCache.Snapshot snapshot; synchronized (mHttpDiskCacheLock) { // Wait for disk cache to initialize while (mHttpDiskCacheStarting) { try { mHttpDiskCacheLock.wait(); } catch (InterruptedException e) { } } if (mHttpDiskCache != null) { try { snapshot = mHttpDiskCache.get(key); if (snapshot == null) { LogUtils.d(TAG, "processBitmap, not found in http cache, downloading..."); DiskLruCache.Editor editor = mHttpDiskCache.edit(key); if (editor != null) { if (downloadUrlToStream2(data, editor.newOutputStream(DISK_CACHE_INDEX))) { editor.commit(); } else { editor.abort(); } } snapshot = mHttpDiskCache.get(key); } if (snapshot != null) { // if (BuildConfig.DEBUG) { // LogUtils.d(TAG, HTTP_CACHE_DIR + " cache hit"); // } fileInputStream = (FileInputStream) snapshot.getInputStream(DISK_CACHE_INDEX); fileDescriptor = fileInputStream.getFD(); } } catch (IOException e) { LogUtils.e(TAG, "processBitmap - " + e); } catch (IllegalStateException e) { LogUtils.e(TAG, "processBitmap - " + e); } finally { if (fileDescriptor == null && fileInputStream != null) { try { fileInputStream.close(); } catch (IOException e) { } } } } } Bitmap bitmap = null; if (fileDescriptor != null) { bitmap = decodeSampledBitmapFromDescriptor(fileDescriptor, width, height, getImageCache()); } if (fileInputStream != null) { try { fileInputStream.close(); } catch (IOException e) { } } return bitmap; } private Bitmap processVideoThumb(Object data) { String path = ((VideoThumbRequest) data).getPath(); return ThumbnailUtils.createVideoThumbnail(path, Thumbnails.MICRO_KIND); } private Bitmap processPhotoThumb(Object data, int reqWidth, int reqHeight) { String path = ((PhotoThumbRequest) data).getPath(); Bitmap bitmap = Utility.decodeSampledBitmapFromPath(path, reqWidth, reqHeight); return fixOrientation(bitmap, path, reqWidth, reqHeight); } @Override protected Bitmap processBitmap(Object data, int width, int height) { String url = ""; String urlCache = getCacheKeyFromObject(data); Bitmap bitmap = null; if (data instanceof ImageRequest) { ImageRequest imageRequest = (ImageRequest) data; if (TextUtils.isEmpty(imageRequest.img_id) || TextUtils.isEmpty(imageRequest.getToken())) { return null; } url = imageRequest.toURL(); } else if (data instanceof ImageRequestWithSize) { ImageRequestWithSize imageRequest = (ImageRequestWithSize) data; if (TextUtils.isEmpty(imageRequest.img_id) || TextUtils.isEmpty(imageRequest.getToken())) { return null; } url = imageRequest.toURL(); } else if (data instanceof VideoThumbRequest) { return processVideoThumb(data); } else if (data instanceof PhotoThumbRequest) { return processPhotoThumb(data, width, height); } else if (data instanceof CircleImageRequest) { url = ((CircleImageRequest) data).toURL(); } else { url = String.valueOf(data); } bitmap = processBitmap(url, width, height, urlCache); return bitmap; } /** * Download a bitmap from a URL and write the content to an output stream. * * @param urlString * The URL to fetch * @return true if successful, false otherwise */ public boolean downloadUrlToStream(String urlString, OutputStream outputStream) { disableConnectionReuseIfNecessary(); BufferedOutputStream out = null; BufferedInputStream in = null; try { final AndroidHttpClient client = AndroidHttpClient.newInstance("Android"); final HttpGet getRequest = new HttpGet(urlString); HttpResponse response = client.execute(getRequest); final int statusCode = response.getStatusLine().getStatusCode(); if (statusCode != HttpStatus.SC_OK) { LogUtils.w("ImageDownloader", "Error " + statusCode + " while retrieving bitmap from " + urlString); return false; } final HttpEntity entity = response.getEntity(); if (entity != null) { try { in = new BufferedInputStream(entity.getContent(), IO_BUFFER_SIZE); out = new BufferedOutputStream(outputStream, IO_BUFFER_SIZE); int b; while ((b = in.read()) != -1) { out.write(b); } } finally { entity.consumeContent(); } } return true; } catch (final IOException e) { LogUtils.e(TAG, "Error in downloadBitmap - " + e); } finally { try { if (out != null) { out.close(); } if (in != null) { in.close(); } } catch (final IOException e) { } } return false; } public boolean downloadUrlToStream2(String urlString, OutputStream outputStream) { disableConnectionReuseIfNecessary(); HttpURLConnection urlConnection = null; BufferedOutputStream out = null; BufferedInputStream in = null; try { final URL url = new URL(urlString); urlConnection = (HttpURLConnection) url.openConnection(); in = new BufferedInputStream(urlConnection.getInputStream(), IO_BUFFER_SIZE); out = new BufferedOutputStream(outputStream, IO_BUFFER_SIZE); int b; while ((b = in.read()) != -1) { out.write(b); } return true; } catch (final IOException e) { LogUtils.e(TAG, "Error in downloadBitmap - " + e); } finally { if (urlConnection != null) { urlConnection.disconnect(); } try { if (out != null) { out.close(); } if (in != null) { in.close(); } } catch (final IOException e) { } } return false; } /** * Workaround for bug pre-Froyo, see here for more info: * http://android-developers.blogspot.com/2011/09/androids-http-clients.html */ public static void disableConnectionReuseIfNecessary() { // HTTP connection reuse which was buggy pre-froyo if (Build.VERSION.SDK_INT < Build.VERSION_CODES.FROYO) { System.setProperty("http.keepAlive", "false"); } } @Override protected String getCacheKeyFromObject(Object object) { String key; if (object instanceof ImageRequest) { ImageRequest imageRequest = (ImageRequest) object; key = imageRequest.toURLCache(); } else if (object instanceof VideoThumbRequest) { key = ((VideoThumbRequest) object).getPath(); } else if (object instanceof PhotoThumbRequest) { key = ((PhotoThumbRequest) object).getPath(); } else if (object instanceof CircleImageRequest) { key = ((CircleImageRequest) object).getCircleImageIdUnique(); } else { key = String.valueOf(object); } return key; } public File getOriginalImage(Object object) { String urlCache = getCacheKeyFromObject(object); String key = ImageCache.hashKeyForDisk(urlCache); File file = new File(mHttpCacheDir, key + "." + DISK_CACHE_INDEX); return file; } /** * only use for fix orientaion * * @param urlCache * @return */ private File getFileFromUrlCache(String urlCache) { String key = ImageCache.hashKeyForDisk(urlCache); File file = new File(mHttpCacheDir, key + "." + DISK_CACHE_INDEX); return file; } }