Java tutorial
/* * GeoTools - The Open Source Java GIS Toolkit * http://geotools.org * * (C) 2002-2008, Open Source Geospatial Foundation (OSGeo) * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; * version 2.1 of the License. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. */ package org.geotools.data.wfs.protocol.http; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.URL; import java.util.Map; import java.util.logging.Level; import java.util.zip.GZIPInputStream; import org.apache.commons.httpclient.Header; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.HttpMethodBase; import org.apache.commons.httpclient.HttpStatus; import org.apache.commons.httpclient.URI; import org.apache.commons.httpclient.URIException; import org.apache.commons.httpclient.methods.GetMethod; import org.apache.commons.httpclient.methods.PostMethod; import org.apache.commons.httpclient.methods.RequestEntity; import org.geotools.factory.GeoTools; /** * Default implementation of {@link HTTPProtocol} based on apache's common-http-client * * @author Gabriel Roldan (OpenGeo) * @version $Id$ * @since 2.6 * * * * @source $URL$ * http://gtsvn.refractions.net/trunk/modules/plugin/wfs/src/main/java/org/geotools/data * /wfs/protocol/http/DefaultHTTPProtocol.java $ */ @SuppressWarnings("nls") public class DefaultHTTPProtocol extends AbstractHttpProtocol implements HTTPProtocol { /** * An {@link HTTPResponse} wrapping an executed {@link GetMethod} or {@link PostMethod} from the * apache commons-httpclient package * * @author Gabriel Roldan (OpenGeo) */ public class HTTPClientResponse implements HTTPResponse { private HttpMethodBase method; public HTTPClientResponse(HttpMethodBase method) { this.method = method; } /** * @see HTTPResponse#getResponseStream() */ public InputStream getResponseStream() throws IOException { final InputStream in; { InputStream responseStream = method.getResponseBodyAsStream(); String encoding = getResponseHeader("Content-Encoding"); if (encoding != null) { if (encoding.toLowerCase().indexOf("gzip") > -1) { LOGGER.finest("Response is GZIP encoded, wrapping with gzip input stream"); responseStream = new GZIPInputStream(responseStream); } } else { LOGGER.finest("HTTP response is not gzip encoded"); } in = responseStream; } InputStream releaseConnectionInputStream = new InputStream() { @Override public int read() throws IOException { return in.read(); } @Override public void close() throws IOException { method.releaseConnection(); } }; return releaseConnectionInputStream; } public String getContentType() { return getResponseHeader("Content-Type"); } public String getResponseCharset() { String responseCharSet = method.getResponseCharSet(); return responseCharSet; } /** * @see HTTPResponse#getResponseHeader() */ public String getResponseHeader(String headerName) { Header header = method.getResponseHeader(headerName); String headerValue = null; if (header != null) { headerValue = header.getValue(); } return headerValue; } /** * @see HTTPResponse#getTargetUrl() */ public String getTargetUrl() { try { URI uri = method.getURI(); return uri.toString(); } catch (URIException e) { LOGGER.log(Level.FINE, "can't get HTTP request URI", e); } return null; } public String toString() { StringBuilder sb = new StringBuilder(getClass().getSimpleName()); sb.append("[Method=").append(method.getName()); sb.append("\n\tHTTP version=").append(method.getEffectiveVersion()); sb.append("\n\tstatus code=").append(method.getStatusCode()); sb.append("\n\tpath=").append(method.getPath()); sb.append("\n\tquery string=").append(method.getQueryString()); sb.append("\n\tresponse charset=").append(getResponseCharset()); Header[] responseHeaders = method.getResponseHeaders(); sb.append("\n\tresponse headers="); for (Header header : responseHeaders) { sb.append(header.toExternalForm()); } sb.append("]"); return sb.toString(); } } public HTTPResponse issuePost(final URL targetUrl, final POSTCallBack callback) throws IOException { if (LOGGER.isLoggable(Level.FINEST)) { LOGGER.finest("About to issue POST request to " + targetUrl.toExternalForm()); } final String uri = targetUrl.toExternalForm(); final PostMethod postRequest = new PostMethod(uri); final RequestEntity requestEntity = new RequestEntity() { public long getContentLength() { return callback.getContentLength(); } public String getContentType() { return callback.getContentType(); } public boolean isRepeatable() { return false; } public void writeRequest(OutputStream out) throws IOException { callback.writeBody(out); } }; postRequest.setRequestEntity(requestEntity); HTTPResponse httpResponse = issueRequest(postRequest); return httpResponse; } public HTTPResponse issueGet(final URL baseUrl, final Map<String, String> kvp) throws IOException { if (LOGGER.isLoggable(Level.FINEST)) { LOGGER.finest( "About to issue GET request to " + baseUrl.toExternalForm() + " with query parameters: " + kvp); } final String uri = createUri(baseUrl, kvp); GetMethod getRequest = new GetMethod(uri); HTTPResponse httpResponse = issueRequest(getRequest); return httpResponse; } private HttpClient client; /** * * @param httpRequest * either a {@link HttpMethod} or {@link PostMethod} set up with the request to be * sent * @return * @throws IOException */ private HTTPResponse issueRequest(final HttpMethodBase httpRequest) throws IOException { if (LOGGER.isLoggable(Level.FINE)) { LOGGER.fine("Executing HTTP request: " + httpRequest.getURI()); } if (client == null) { client = new HttpClient(); client.getParams().setParameter("http.useragent", "GeoTools " + GeoTools.getVersion() + " WFS DataStore"); } if (timeoutMillis > 0) { client.getParams().setSoTimeout(timeoutMillis); } // TODO: remove this System.err.println("Executing HTTP request: " + httpRequest); if (isTryGzip()) { LOGGER.finest("Adding 'Accept-Encoding=gzip' header to request"); httpRequest.addRequestHeader("Accept-Encoding", "gzip"); } int statusCode; try { statusCode = client.executeMethod(httpRequest); } catch (IOException e) { httpRequest.releaseConnection(); throw e; } if (statusCode != HttpStatus.SC_OK) { httpRequest.releaseConnection(); String statusText = HttpStatus.getStatusText(statusCode); throw new IOException("Request failed with status code " + statusCode + "(" + statusText + "): " + httpRequest.getURI()); } HTTPResponse httpResponse = new HTTPClientResponse(httpRequest); if (LOGGER.isLoggable(Level.FINE)) { LOGGER.fine("Got " + httpResponse); } return httpResponse; } }