Java tutorial
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See the License for the * specific language governing permissions and limitations * under the License. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.http.impl.client; import java.io.Closeable; import java.io.IOException; import java.lang.reflect.UndeclaredThrowableException; import java.net.URI; import android.util.Log; import org.apache.http.HttpEntity; import org.apache.http.HttpHost; import org.apache.http.HttpRequest; import org.apache.http.HttpResponse; import org.apache.http.annotation.ThreadSafe; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.HttpClient; import org.apache.http.client.ResponseHandler; import org.apache.http.client.methods.CloseableHttpResponse; import org.apache.http.client.methods.HttpUriRequest; import org.apache.http.client.utils.URIUtilsHC4; import org.apache.http.protocol.HttpContext; import org.apache.http.util.Args; import org.apache.http.util.EntityUtilsHC4; /** * Base implementation of {@link HttpClient} that also implements {@link Closeable}. * * @since 4.3 */ @ThreadSafe public abstract class CloseableHttpClient implements HttpClient, Closeable { private final static String TAG = "HttpClient"; protected abstract CloseableHttpResponse doExecute(HttpHost target, HttpRequest request, HttpContext context) throws IOException, ClientProtocolException; /** * {@inheritDoc} */ public CloseableHttpResponse execute(final HttpHost target, final HttpRequest request, final HttpContext context) throws IOException, ClientProtocolException { return doExecute(target, request, context); } /** * {@inheritDoc} */ public CloseableHttpResponse execute(final HttpUriRequest request, final HttpContext context) throws IOException, ClientProtocolException { Args.notNull(request, "HTTP request"); return doExecute(determineTarget(request), request, context); } private static HttpHost determineTarget(final HttpUriRequest request) throws ClientProtocolException { // A null target may be acceptable if there is a default target. // Otherwise, the null target is detected in the director. HttpHost target = null; final URI requestURI = request.getURI(); if (requestURI.isAbsolute()) { target = URIUtilsHC4.extractHost(requestURI); if (target == null) { throw new ClientProtocolException("URI does not specify a valid host name: " + requestURI); } } return target; } /** * {@inheritDoc} */ public CloseableHttpResponse execute(final HttpUriRequest request) throws IOException, ClientProtocolException { return execute(request, (HttpContext) null); } /** * {@inheritDoc} */ public CloseableHttpResponse execute(final HttpHost target, final HttpRequest request) throws IOException, ClientProtocolException { return doExecute(target, request, (HttpContext) null); } /** * Executes a request using the default context and processes the * response using the given response handler. The content entity associated * with the response is fully consumed and the underlying connection is * released back to the connection manager automatically in all cases * relieving individual {@link ResponseHandler}s from having to manage * resource deallocation internally. * * @param request the request to execute * @param responseHandler the response handler * * @return the response object as generated by the response handler. * @throws IOException in case of a problem or the connection was aborted * @throws ClientProtocolException in case of an http protocol error */ public <T> T execute(final HttpUriRequest request, final ResponseHandler<? extends T> responseHandler) throws IOException, ClientProtocolException { return execute(request, responseHandler, null); } /** * Executes a request using the default context and processes the * response using the given response handler. The content entity associated * with the response is fully consumed and the underlying connection is * released back to the connection manager automatically in all cases * relieving individual {@link ResponseHandler}s from having to manage * resource deallocation internally. * * @param request the request to execute * @param responseHandler the response handler * @param context the context to use for the execution, or * <code>null</code> to use the default context * * @return the response object as generated by the response handler. * @throws IOException in case of a problem or the connection was aborted * @throws ClientProtocolException in case of an http protocol error */ public <T> T execute(final HttpUriRequest request, final ResponseHandler<? extends T> responseHandler, final HttpContext context) throws IOException, ClientProtocolException { final HttpHost target = determineTarget(request); return execute(target, request, responseHandler, context); } /** * Executes a request using the default context and processes the * response using the given response handler. The content entity associated * with the response is fully consumed and the underlying connection is * released back to the connection manager automatically in all cases * relieving individual {@link ResponseHandler}s from having to manage * resource deallocation internally. * * @param target the target host for the request. * Implementations may accept <code>null</code> * if they can still determine a route, for example * to a default target or by inspecting the request. * @param request the request to execute * @param responseHandler the response handler * * @return the response object as generated by the response handler. * @throws IOException in case of a problem or the connection was aborted * @throws ClientProtocolException in case of an http protocol error */ public <T> T execute(final HttpHost target, final HttpRequest request, final ResponseHandler<? extends T> responseHandler) throws IOException, ClientProtocolException { return execute(target, request, responseHandler, null); } /** * Executes a request using the default context and processes the * response using the given response handler. The content entity associated * with the response is fully consumed and the underlying connection is * released back to the connection manager automatically in all cases * relieving individual {@link ResponseHandler}s from having to manage * resource deallocation internally. * * @param target the target host for the request. * Implementations may accept <code>null</code> * if they can still determine a route, for example * to a default target or by inspecting the request. * @param request the request to execute * @param responseHandler the response handler * @param context the context to use for the execution, or * <code>null</code> to use the default context * * @return the response object as generated by the response handler. * @throws IOException in case of a problem or the connection was aborted * @throws ClientProtocolException in case of an http protocol error */ public <T> T execute(final HttpHost target, final HttpRequest request, final ResponseHandler<? extends T> responseHandler, final HttpContext context) throws IOException, ClientProtocolException { Args.notNull(responseHandler, "Response handler"); final HttpResponse response = execute(target, request, context); final T result; try { result = responseHandler.handleResponse(response); } catch (final Exception t) { final HttpEntity entity = response.getEntity(); try { EntityUtilsHC4.consume(entity); } catch (final Exception t2) { // Log this exception. The original exception is more // important and will be thrown to the caller. if (Log.isLoggable(TAG, Log.WARN)) { Log.w(TAG, "Error consuming content after an exception.", t2); } } if (t instanceof RuntimeException) { throw (RuntimeException) t; } if (t instanceof IOException) { throw (IOException) t; } throw new UndeclaredThrowableException(t); } // Handling the response was successful. Ensure that the content has // been fully consumed. final HttpEntity entity = response.getEntity(); EntityUtilsHC4.consume(entity); return result; } }