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.CacheControl; import com.squareup.okhttp.OkHttpClient; import com.squareup.okhttp.ResponseBody; import com.squareup.okhttp.Request; import java.io.File; import java.io.IOException; import java.util.concurrent.TimeUnit; /** A {@link Downloader} which uses OkHttp to download images. */ public class OkHttpDownloader implements Downloader { private static OkHttpClient defaultOkHttpClient() { OkHttpClient client = new OkHttpClient(); client.setConnectTimeout(Utils.DEFAULT_CONNECT_TIMEOUT_MILLIS, TimeUnit.MILLISECONDS); client.setReadTimeout(Utils.DEFAULT_READ_TIMEOUT_MILLIS, TimeUnit.MILLISECONDS); client.setWriteTimeout(Utils.DEFAULT_WRITE_TIMEOUT_MILLIS, TimeUnit.MILLISECONDS); return client; } private final OkHttpClient client; /** * Create new downloader that uses OkHttp. This will install an image cache into your application * cache directory. */ public OkHttpDownloader(final Context context) { this(Utils.createDefaultCacheDir(context)); } /** * Create new downloader that uses OkHttp. This will install an image cache into the specified * directory. * * @param cacheDir The directory in which the cache should be stored */ public OkHttpDownloader(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 OkHttpDownloader(final Context context, final long maxSize) { this(Utils.createDefaultCacheDir(context), maxSize); } /** * Create new downloader that uses OkHttp. This will install an image cache into the specified * directory. * * @param cacheDir The directory in which the cache should be stored * @param maxSize The size limit for the cache. */ public OkHttpDownloader(final File cacheDir, final long maxSize) { this(defaultOkHttpClient()); try { 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 OkHttpDownloader(OkHttpClient client) { this.client = client; } protected final OkHttpClient getClient() { return client; } @Override public Response load(Uri uri, int networkPolicy) throws IOException { CacheControl cacheControl = null; if (networkPolicy != 0) { if (NetworkPolicy.isOfflineOnly(networkPolicy)) { cacheControl = CacheControl.FORCE_CACHE; } else { CacheControl.Builder builder = new CacheControl.Builder(); if (!NetworkPolicy.shouldReadFromDiskCache(networkPolicy)) { builder.noCache(); } if (!NetworkPolicy.shouldWriteToDiskCache(networkPolicy)) { builder.noStore(); } cacheControl = builder.build(); } } Request.Builder builder = new Request.Builder().url(uri.toString()); if (cacheControl != null) { builder.cacheControl(cacheControl); } com.squareup.okhttp.Response response = client.newCall(builder.build()).execute(); int responseCode = response.code(); if (responseCode >= 300) { response.body().close(); throw new ResponseException(responseCode + " " + response.message(), networkPolicy, responseCode); } boolean fromCache = response.cacheResponse() != null; ResponseBody responseBody = response.body(); return new Response(responseBody.byteStream(), fromCache, responseBody.contentLength()); } @Override public void shutdown() { com.squareup.okhttp.Cache cache = client.getCache(); if (cache != null) { try { cache.close(); } catch (IOException ignored) { } } } }