Java tutorial
/* * Copyright (C) 2009 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.ocp.picasa; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.util.zip.GZIPInputStream; import java.util.zip.GZIPOutputStream; import org.apache.http.Header; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.methods.HttpPost; import org.apache.http.client.methods.HttpUriRequest; import org.apache.http.client.params.HttpClientParams; import org.apache.http.conn.scheme.PlainSocketFactory; import org.apache.http.conn.scheme.Scheme; import org.apache.http.conn.scheme.SchemeRegistry; import org.apache.http.entity.ByteArrayEntity; import org.apache.http.entity.InputStreamEntity; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager; import org.apache.http.params.BasicHttpParams; import org.apache.http.params.HttpConnectionParams; import org.apache.http.params.HttpParams; import org.apache.http.params.HttpProtocolParams; import android.text.TextUtils; import android.util.Log; import com.ocp.media.Gallery; public final class GDataClient { private static final String TAG = "GDataClient"; private static final String USER_AGENT = "Cooliris-GData/1.0; gzip"; private static final String X_HTTP_METHOD_OVERRIDE = "X-HTTP-Method-Override"; private static final String IF_MATCH = "If-Match"; private static final int CONNECTION_TIMEOUT = 20000; // ms. private static final int MIN_GZIP_SIZE = 512; public static final HttpParams HTTP_PARAMS; public static final ThreadSafeClientConnManager HTTP_CONNECTION_MANAGER; private final DefaultHttpClient mHttpClient = new DefaultHttpClient(HTTP_CONNECTION_MANAGER, HTTP_PARAMS); private String mAuthToken; static { // Prepare HTTP parameters. HttpParams params = new BasicHttpParams(); HttpConnectionParams.setStaleCheckingEnabled(params, false); HttpConnectionParams.setConnectionTimeout(params, CONNECTION_TIMEOUT); HttpConnectionParams.setSoTimeout(params, CONNECTION_TIMEOUT); HttpClientParams.setRedirecting(params, true); HttpProtocolParams.setUserAgent(params, USER_AGENT); HTTP_PARAMS = params; // Register HTTP protocol. SchemeRegistry schemeRegistry = new SchemeRegistry(); schemeRegistry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80)); // Create the connection manager. HTTP_CONNECTION_MANAGER = new ThreadSafeClientConnManager(params, schemeRegistry); } public static final class Operation { public String inOutEtag; public int outStatus; public InputStream outBody; } public void setAuthToken(String authToken) { mAuthToken = authToken; } public void get(String feedUrl, Operation operation) throws IOException { callMethod(new HttpGet(feedUrl), operation); } public void post(String feedUrl, byte[] data, String contentType, Operation operation) throws IOException { ByteArrayEntity entity = getCompressedEntity(data); entity.setContentType(contentType); HttpPost post = new HttpPost(feedUrl); post.setEntity(entity); callMethod(post, operation); } public void put(String feedUrl, byte[] data, String contentType, Operation operation) throws IOException { ByteArrayEntity entity = getCompressedEntity(data); entity.setContentType(contentType); HttpPost post = new HttpPost(feedUrl); post.setHeader(X_HTTP_METHOD_OVERRIDE, "PUT"); post.setEntity(entity); callMethod(post, operation); } public void putStream(String feedUrl, InputStream stream, String contentType, Operation operation) throws IOException { InputStreamEntity entity = new InputStreamEntity(stream, -1); entity.setContentType(contentType); HttpPost post = new HttpPost(feedUrl); post.setHeader(X_HTTP_METHOD_OVERRIDE, "PUT"); post.setEntity(entity); callMethod(post, operation); } public void delete(String feedUrl, Operation operation) throws IOException { HttpPost post = new HttpPost(feedUrl); String etag = operation.inOutEtag; post.setHeader(X_HTTP_METHOD_OVERRIDE, "DELETE"); post.setHeader(IF_MATCH, etag != null ? etag : "*"); callMethod(post, operation); } private void callMethod(HttpUriRequest request, Operation operation) throws IOException { // Specify GData protocol version 2.0. request.addHeader("GData-Version", "2"); // Indicate support for gzip-compressed responses. request.addHeader("Accept-Encoding", "gzip"); // Specify authorization token if provided. String authToken = mAuthToken; if (!TextUtils.isEmpty(authToken)) { request.addHeader("Authorization", "GoogleLogin auth=" + authToken); } // Specify the ETag of a prior response, if available. String etag = operation.inOutEtag; if (etag != null) { request.addHeader("If-None-Match", etag); } // Execute the HTTP request. HttpResponse httpResponse = null; try { httpResponse = mHttpClient.execute(request); } catch (IOException e) { Log.w(Gallery.TAG, TAG + ": " + "Request failed: " + request.getURI()); throw e; } // Get the status code and response body. int status = httpResponse.getStatusLine().getStatusCode(); InputStream stream = null; HttpEntity entity = httpResponse.getEntity(); if (entity != null) { // Wrap the entity input stream in a GZIP decoder if necessary. stream = entity.getContent(); if (stream != null) { Header header = entity.getContentEncoding(); if (header != null) { if (header.getValue().contains("gzip")) { stream = new GZIPInputStream(stream); } } } } // Return the stream if successful. Header etagHeader = httpResponse.getFirstHeader("ETag"); operation.outStatus = status; operation.inOutEtag = etagHeader != null ? etagHeader.getValue() : null; operation.outBody = stream; } private ByteArrayEntity getCompressedEntity(byte[] data) throws IOException { ByteArrayEntity entity; if (data.length >= MIN_GZIP_SIZE) { ByteArrayOutputStream byteOutput = new ByteArrayOutputStream(data.length / 2); GZIPOutputStream gzipOutput = new GZIPOutputStream(byteOutput); gzipOutput.write(data); gzipOutput.close(); entity = new ByteArrayEntity(byteOutput.toByteArray()); } else { entity = new ByteArrayEntity(data); } return entity; } public static String inputStreamToString(InputStream stream) { if (stream != null) { try { ByteArrayOutputStream bytes = new ByteArrayOutputStream(); byte[] buffer = new byte[4096]; int bytesRead; while ((bytesRead = stream.read(buffer)) != -1) { bytes.write(buffer, 0, bytesRead); } return new String(bytes.toString()); } catch (IOException e) { // Fall through and return null. } } return null; } }