Java tutorial
package ar.com.aleatoria.ue.rest; /* * Copyright 2002-2012 the original author or authors. * * 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. */ import java.io.FilterOutputStream; import java.io.IOException; import java.io.OutputStream; import java.net.HttpURLConnection; import java.net.URI; import java.net.URISyntaxException; import java.util.List; import java.util.Map; import org.springframework.http.HttpHeaders; import org.springframework.http.HttpMethod; import org.springframework.http.client.AbstractClientHttpRequest; import org.springframework.http.client.ClientHttpRequest; import org.springframework.http.client.ClientHttpResponse; import org.springframework.http.client.SimpleClientHttpRequestFactory; import android.os.Build; /** * {@link ClientHttpRequest} implementation that uses standard J2SE facilities to execute streaming requests. Created * via the {@link SimpleClientHttpRequestFactory}. * * @author Arjen Poutsma * @author Roy Clarkson * @since 1.0 * @see SimpleClientHttpRequestFactory#createRequest(java.net.URI, HttpMethod) */ final class SimpleStreamingClientHttpRequest extends AbstractClientHttpRequest { private static final Boolean olderThanFroyo = (Build.VERSION.SDK_INT < Build.VERSION_CODES.FROYO); private final HttpURLConnection connection; private final int chunkSize; private OutputStream body; SimpleStreamingClientHttpRequest(HttpURLConnection connection, int chunkSize) { this.connection = connection; this.chunkSize = chunkSize; // Bugs with reusing connections in Android versions older than Froyo (2.2) if (olderThanFroyo) { System.setProperty("http.keepAlive", "false"); } } public HttpMethod getMethod() { return HttpMethod.valueOf(this.connection.getRequestMethod()); } public URI getURI() { try { return this.connection.getURL().toURI(); } catch (URISyntaxException ex) { throw new IllegalStateException("Could not get HttpURLConnection URI: " + ex.getMessage(), ex); } } @Override protected OutputStream getBodyInternal(HttpHeaders headers) throws IOException { if (this.body == null) { int contentLength = (int) headers.getContentLength(); if (contentLength >= 0 && !olderThanFroyo) { this.connection.setFixedLengthStreamingMode(contentLength); } else { this.connection.setChunkedStreamingMode(this.chunkSize); } writeHeaders(headers); this.connection.connect(); this.body = this.connection.getOutputStream(); } return new NonClosingOutputStream(this.body); } @Override protected ClientHttpResponse executeInternal(HttpHeaders headers) throws IOException { try { if (this.body != null) { this.body.close(); } else { writeHeaders(headers); this.connection.connect(); } } catch (IOException ex) { // ignore } return new SimpleClientHttpResponse(this.connection); } private void writeHeaders(HttpHeaders headers) { for (Map.Entry<String, List<String>> entry : headers.entrySet()) { String headerName = entry.getKey(); for (String headerValue : entry.getValue()) { if (shouldAllowConnectionReuse(headerName, headerValue)) { this.connection.addRequestProperty(headerName, headerValue); } } } } private boolean shouldAllowConnectionReuse(String headerName, String headerValue) { // Bugs with reusing connections in Android versions older than Froyo (2.2) if (olderThanFroyo && headerName.equals("Connection") && headerValue.equals("Keep-Alive")) { return false; } return true; } private static class NonClosingOutputStream extends FilterOutputStream { private NonClosingOutputStream(OutputStream out) { super(out); } @Override public void close() throws IOException { } } }