Java tutorial
/* * Copyright (C) 2013 Square, Inc. * * 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.squareup.picasso; import android.content.Context; import android.net.Uri; import com.squareup.okhttp.OkHttpClient; import com.squareup.okhttp.OkUrlFactory; import java.io.File; import java.io.IOException; import java.net.HttpURLConnection; import java.net.URL; import static com.squareup.picasso.Utils.parseResponseSourceHeader; /** * A {@link com.squareup.picasso.Downloader} which uses OkHttp to download images. */ public class OkHttpDownloaderWithSetting implements Downloader { static final String RESPONSE_SOURCE_ANDROID = "X-Android-Response-Source"; static final String RESPONSE_SOURCE_OKHTTP = "OkHttp-Response-Source"; private final OkUrlFactory urlFactory; /** * File cache max age. */ private int maxAge; public int getMaxAge() { return maxAge; } /** * Set file cache max age.</p> * ex.) 86400 means one day. * * @param maxAge file cache max age */ public void setMaxAge(int maxAge) { this.maxAge = maxAge; } /** * Create new downloader that uses OkHttp. This will install an image cache into your application * cache directory. */ public OkHttpDownloaderWithSetting(final Context context) { this(Utils.createDefaultCacheDir(context)); } /** * Create new downloader that uses OkHttp. This will install an image cache into your application * cache directory. * * @param cacheDir The directory in which the cache should be stored */ public OkHttpDownloaderWithSetting(final File cacheDir) { this(cacheDir, Utils.calculateDiskCacheSize(cacheDir)); } /** * Create new downloader that uses OkHttp. This will install an image cache into your application * cache directory. * * @param maxSize The size limit for the cache. */ public OkHttpDownloaderWithSetting(final Context context, final long maxSize) { this(Utils.createDefaultCacheDir(context), maxSize); } /** * Create new downloader that uses OkHttp. This will install an image cache into your application * cache directory. * * @param cacheDir The directory in which the cache should be stored * @param maxSize The size limit for the cache. */ public OkHttpDownloaderWithSetting(final File cacheDir, final long maxSize) { this(new OkHttpClient()); try { urlFactory.client().setCache(new com.squareup.okhttp.Cache(cacheDir, maxSize)); } catch (IOException ignored) { } } /** * Create a new downloader that uses the specified OkHttp instance. A response cache will not be * automatically configured. */ public OkHttpDownloaderWithSetting(OkHttpClient client) { this.urlFactory = new OkUrlFactory(client); } protected HttpURLConnection openConnection(Uri uri) throws IOException { HttpURLConnection connection = urlFactory.open(new URL(uri.toString())); connection.setConnectTimeout(Utils.DEFAULT_CONNECT_TIMEOUT); connection.setReadTimeout(Utils.DEFAULT_READ_TIMEOUT); return connection; } protected OkHttpClient getClient() { return urlFactory.client(); } @Override public Response load(Uri uri, boolean localCacheOnly) throws IOException { HttpURLConnection connection = openConnection(uri); connection.setUseCaches(true); if (localCacheOnly) { connection.setRequestProperty("Cache-Control", "only-if-cached,max-age=" + maxAge); } int responseCode = connection.getResponseCode(); if (responseCode >= 300) { connection.disconnect(); throw new ResponseException(responseCode + " " + connection.getResponseMessage()); } String responseSource = connection.getHeaderField(RESPONSE_SOURCE_OKHTTP); if (responseSource == null) { responseSource = connection.getHeaderField(RESPONSE_SOURCE_ANDROID); } long contentLength = connection.getHeaderFieldInt("Content-Length", -1); boolean fromCache = parseResponseSourceHeader(responseSource); return new Response(connection.getInputStream(), fromCache, contentLength); } }