Java tutorial
/* * ============================================================================ * The Apache Software License, Version 1.1 * ============================================================================ * * Copyright (C) 2002 The Apache Software Foundation. All rights reserved. * * Redistribution and use in source and binary forms, with or without modifica- * tion, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * 3. The end-user documentation included with the redistribution, if any, must * include the following acknowledgment: "This product includes software * developed by SuperBonBon Industries (http://www.sbbi.net/)." * Alternately, this acknowledgment may appear in the software itself, if * and wherever such third-party acknowledgments normally appear. * * 4. The names "UPNPLib" and "SuperBonBon Industries" must not be * used to endorse or promote products derived from this software without * prior written permission. For written permission, please contact * info@sbbi.net. * * 5. Products derived from this software may not be called * "SuperBonBon Industries", nor may "SBBI" appear in their name, * without prior written permission of SuperBonBon Industries. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, * INDIRECT,INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU- * DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * This software consists of voluntary contributions made by many individuals * on behalf of SuperBonBon Industries. For more information on * SuperBonBon Industries, please see <http://www.sbbi.net/>. */ package net.sbbi.upnp.messages; import org.xml.sax.*; import javax.xml.parsers.*; import java.io.*; import java.net.HttpURLConnection; import java.net.URL; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import net.sbbi.upnp.services.*; /** * This class is used to create state variable messages to * comminicate with the device * @author <a href="mailto:superbonbon@sbbi.net">SuperBonBon</a> * @version 1.0 */ public class StateVariableMessage { private final static Log log = LogFactory.getLog(StateVariableMessage.class); private UPNPService service; private ServiceStateVariable serviceStateVar; protected StateVariableMessage(UPNPService service, ServiceStateVariable serviceStateVar) { this.service = service; this.serviceStateVar = serviceStateVar; } /** * Executes the state variable query and retuns the UPNP device response, according to the UPNP specs, * this method could take up to 30 secs to process ( time allowed for a device to respond to a request ) * @return a state variable response object containing the variable value * @throws IOException if some IOException occurs during message send and reception process * @throws UPNPResponseException if an UPNP error message is returned from the server * or if some parsing exception occurs ( detailErrorCode = 899, detailErrorDescription = SAXException message ) */ public StateVariableResponse service() throws IOException, UPNPResponseException { StateVariableResponse rtrVal = null; UPNPResponseException upnpEx = null; IOException ioEx = null; StringBuffer body = new StringBuffer(256); body.append("<?xml version=\"1.0\"?>\r\n"); body.append("<s:Envelope xmlns:s=\"http://schemas.xmlsoap.org/soap/envelope/\""); body.append(" s:encodingStyle=\"http://schemas.xmlsoap.org/soap/encoding/\">"); body.append("<s:Body>"); body.append("<u:QueryStateVariable xmlns:u=\"urn:schemas-upnp-org:control-1-0\">"); body.append("<u:varName>").append(serviceStateVar.getName()).append("</u:varName>"); body.append("</u:QueryStateVariable>"); body.append("</s:Body>"); body.append("</s:Envelope>"); if (log.isDebugEnabled()) log.debug("POST prepared for URL " + service.getControlURL()); URL url = new URL(service.getControlURL().toString()); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setDoInput(true); conn.setDoOutput(true); conn.setUseCaches(false); conn.setRequestMethod("POST"); HttpURLConnection.setFollowRedirects(false); //conn.setConnectTimeout( 30000 ); conn.setRequestProperty("HOST", url.getHost() + ":" + url.getPort()); conn.setRequestProperty("SOAPACTION", "\"urn:schemas-upnp-org:control-1-0#QueryStateVariable\""); conn.setRequestProperty("CONTENT-TYPE", "text/xml; charset=\"utf-8\""); conn.setRequestProperty("CONTENT-LENGTH", Integer.toString(body.length())); OutputStream out = conn.getOutputStream(); out.write(body.toString().getBytes()); out.flush(); conn.connect(); InputStream input = null; if (log.isDebugEnabled()) log.debug("executing query :\n" + body); try { input = conn.getInputStream(); } catch (IOException ex) { // java can throw an exception if he error code is 500 or 404 or something else than 200 // but the device sends 500 error message with content that is required // this content is accessible with the getErrorStream input = conn.getErrorStream(); } if (input != null) { int response = conn.getResponseCode(); String responseBody = getResponseBody(input); if (log.isDebugEnabled()) log.debug("received response :\n" + responseBody); SAXParserFactory saxParFact = SAXParserFactory.newInstance(); saxParFact.setValidating(false); saxParFact.setNamespaceAware(true); StateVariableResponseParser msgParser = new StateVariableResponseParser(serviceStateVar); StringReader stringReader = new StringReader(responseBody); InputSource src = new InputSource(stringReader); try { SAXParser parser = saxParFact.newSAXParser(); parser.parse(src, msgParser); } catch (ParserConfigurationException confEx) { // should never happen // we throw a runtimeException to notify the env problem throw new RuntimeException( "ParserConfigurationException during SAX parser creation, please check your env settings:" + confEx.getMessage()); } catch (SAXException saxEx) { // kind of tricky but better than nothing.. upnpEx = new UPNPResponseException(899, saxEx.getMessage()); } finally { try { input.close(); } catch (IOException ex) { // ignoring } } if (upnpEx == null) { if (response == HttpURLConnection.HTTP_OK) { rtrVal = msgParser.getStateVariableResponse(); } else if (response == HttpURLConnection.HTTP_INTERNAL_ERROR) { upnpEx = msgParser.getUPNPResponseException(); } else { ioEx = new IOException("Unexpected server HTTP response:" + response); } } } try { out.close(); } catch (IOException ex) { // ignore } conn.disconnect(); if (upnpEx != null) { throw upnpEx; } if (rtrVal == null && ioEx == null) { ioEx = new IOException("Unable to receive a response from the UPNP device"); } if (ioEx != null) { throw ioEx; } return rtrVal; } private String getResponseBody(InputStream in) throws IOException { byte[] buffer = new byte[256]; int readen = 0; StringBuffer content = new StringBuffer(256); while ((readen = in.read(buffer)) != -1) { content.append(new String(buffer, 0, readen)); } // some devices add \0 chars at XML message end // which causes XML parsing errors... int len = content.length(); while (content.charAt(len - 1) == '\0') { len--; content.setLength(len); } return content.toString().trim(); } }