Java tutorial
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For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.http.impl.client; import java.io.IOException; import java.net.URI; import org.apache.http.HttpEntity; import org.apache.http.HttpEntityEnclosingRequest; import org.apache.http.HttpException; import org.apache.http.HttpHost; import org.apache.http.HttpRequest; import org.apache.http.HttpRequestInterceptor; import org.apache.http.HttpResponse; import org.apache.http.HttpResponseInterceptor; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.HttpClient; import org.apache.http.client.ResponseHandler; import org.apache.http.client.methods.HttpUriRequest; import org.apache.http.client.protocol.RequestAcceptEncoding; import org.apache.http.client.protocol.ResponseContentEncoding; import org.apache.http.client.utils.URIUtils; import org.apache.http.conn.ClientConnectionManager; import org.apache.http.params.HttpParams; import org.apache.http.protocol.BasicHttpContext; import org.apache.http.protocol.HttpContext; import org.apache.http.util.EntityUtils; /** * <p>Decorator adding support for compressed responses. This class sets * the <code>Accept-Encoding</code> header on requests to indicate * support for the <code>gzip</code> and <code>deflate</code> * compression schemes; it then checks the <code>Content-Encoding</code> * header on the response to uncompress any compressed response bodies. * The {@link java.io.InputStream} of the entity will contain the uncompressed * content.</p> * * <p><b>N.B.</b> Any upstream clients of this class need to be aware that * this effectively obscures visibility into the length of a server * response body, since the <code>Content-Length</code> header will * correspond to the compressed entity length received from the server, * but the content length experienced by reading the response body may * be different (hopefully higher!).</p> * * <p>That said, this decorator is compatible with the * <code>CachingHttpClient</code> in that the two decorators can be added * in either order and still have cacheable responses be cached.</p> * * @since 4.2 * * @deprecated (4.3) use {@link HttpClientBuilder} */ @Deprecated public class DecompressingHttpClient implements HttpClient { private final HttpClient backend; private final HttpRequestInterceptor acceptEncodingInterceptor; private final HttpResponseInterceptor contentEncodingInterceptor; /** * Constructs a decorator to ask for and handle compressed * entities on the fly. */ public DecompressingHttpClient() { this(new DefaultHttpClient()); } /** * Constructs a decorator to ask for and handle compressed * entities on the fly. * @param backend the {@link HttpClient} to use for actually * issuing requests */ public DecompressingHttpClient(final HttpClient backend) { this(backend, new RequestAcceptEncoding(), new ResponseContentEncoding()); } DecompressingHttpClient(final HttpClient backend, final HttpRequestInterceptor requestInterceptor, final HttpResponseInterceptor responseInterceptor) { this.backend = backend; this.acceptEncodingInterceptor = requestInterceptor; this.contentEncodingInterceptor = responseInterceptor; } public HttpParams getParams() { return backend.getParams(); } public ClientConnectionManager getConnectionManager() { return backend.getConnectionManager(); } public HttpResponse execute(final HttpUriRequest request) throws IOException, ClientProtocolException { return execute(getHttpHost(request), request, (HttpContext) null); } /** * Gets the HttpClient to issue request. * * @return the HttpClient to issue request */ public HttpClient getHttpClient() { return this.backend; } HttpHost getHttpHost(final HttpUriRequest request) { final URI uri = request.getURI(); return URIUtils.extractHost(uri); } public HttpResponse execute(final HttpUriRequest request, final HttpContext context) throws IOException, ClientProtocolException { return execute(getHttpHost(request), request, context); } public HttpResponse execute(final HttpHost target, final HttpRequest request) throws IOException, ClientProtocolException { return execute(target, request, (HttpContext) null); } public HttpResponse execute(final HttpHost target, final HttpRequest request, final HttpContext context) throws IOException, ClientProtocolException { try { final HttpContext localContext = context != null ? context : new BasicHttpContext(); final HttpRequest wrapped; if (request instanceof HttpEntityEnclosingRequest) { wrapped = new EntityEnclosingRequestWrapper((HttpEntityEnclosingRequest) request); } else { wrapped = new RequestWrapper(request); } acceptEncodingInterceptor.process(wrapped, localContext); final HttpResponse response = backend.execute(target, wrapped, localContext); try { contentEncodingInterceptor.process(response, localContext); if (Boolean.TRUE.equals(localContext.getAttribute(ResponseContentEncoding.UNCOMPRESSED))) { response.removeHeaders("Content-Length"); response.removeHeaders("Content-Encoding"); response.removeHeaders("Content-MD5"); } return response; } catch (final HttpException ex) { EntityUtils.consume(response.getEntity()); throw ex; } catch (final IOException ex) { EntityUtils.consume(response.getEntity()); throw ex; } catch (final RuntimeException ex) { EntityUtils.consume(response.getEntity()); throw ex; } } catch (final HttpException e) { throw new ClientProtocolException(e); } } public <T> T execute(final HttpUriRequest request, final ResponseHandler<? extends T> responseHandler) throws IOException, ClientProtocolException { return execute(getHttpHost(request), request, responseHandler); } public <T> T execute(final HttpUriRequest request, final ResponseHandler<? extends T> responseHandler, final HttpContext context) throws IOException, ClientProtocolException { return execute(getHttpHost(request), request, responseHandler, context); } public <T> T execute(final HttpHost target, final HttpRequest request, final ResponseHandler<? extends T> responseHandler) throws IOException, ClientProtocolException { return execute(target, request, responseHandler, null); } public <T> T execute(final HttpHost target, final HttpRequest request, final ResponseHandler<? extends T> responseHandler, final HttpContext context) throws IOException, ClientProtocolException { final HttpResponse response = execute(target, request, context); try { return responseHandler.handleResponse(response); } finally { final HttpEntity entity = response.getEntity(); if (entity != null) { EntityUtils.consume(entity); } } } }