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1   /**
2    * The contents of this file are subject to the Mozilla Public License Version 1.1
3    * (the "License"); you may not use this file except in compliance with the License.
4    * You may obtain a copy of the License at http://www.mozilla.org/MPL/
5    * Software distributed under the License is distributed on an "AS IS" basis,
6    * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the
7    * specific language governing rights and limitations under the License.
8    *
9    * The Original Code is "Responder.java".  Description:
10   * "Performs the responding role in a message exchange according to HL7's original mode
11   * processing rules."
12   *
13   * The Initial Developer of the Original Code is University Health Network. Copyright (C)
14   * 2002.  All Rights Reserved.
15   *
16   * Contributor(s): ______________________________________.
17   *
18   * Alternatively, the contents of this file may be used under the terms of the
19   * GNU General Public License (the  �GPL�), in which case the provisions of the GPL are
20   * applicable instead of those above.  If you wish to allow use of your version of this
21   * file only under the terms of the GPL and not to allow others to use your version
22   * of this file under the MPL, indicate your decision by deleting  the provisions above
23   * and replace  them with the notice and other provisions required by the GPL License.
24   * If you do not delete the provisions above, a recipient may use your version of
25   * this file under either the MPL or the GPL.
26   *
27   */
28  package ca.uhn.hl7v2.app;
29  
30  import java.io.BufferedReader;
31  import java.io.File;
32  import java.io.FileReader;
33  import java.io.PipedInputStream;
34  import java.io.PipedOutputStream;
35  import java.io.Reader;
36  import java.net.InetSocketAddress;
37  import java.net.Socket;
38  import java.util.HashMap;
39  import java.util.Map;
40  
41  import ca.uhn.hl7v2.HL7Exception;
42  import ca.uhn.hl7v2.model.Message;
43  import ca.uhn.hl7v2.parser.Parser;
44  import ca.uhn.hl7v2.parser.PipeParser;
45  import ca.uhn.hl7v2.protocol.ApplicationRouter;
46  import ca.uhn.hl7v2.protocol.Transportable;
47  import ca.uhn.hl7v2.protocol.impl.TransportableImpl;
48  
49  /**
50   * <p>
51   * Performs the responding role in a message exchange (i.e receiver of the first
52   * message, sender of the response; analagous to the server in a client-server
53   * interaction), according to HL7's original mode processing rules.
54   * </p>
55   * <p>
56   * At the time of writing, enhanced mode, two-phase reply, continuation
57   * messages, and batch processing are unsupported.
58   * </p>
59   * 
60   * @author Bryan Tripp
61   */
62  class Responder {
63  
64  	private ApplicationRouter apps;
65  	private Socket inboundSocket;
66  
67  	/**
68  	 * Creates a new instance of Responder
69  	 */
70  	public Responder(Socket theInboundSocket) {
71  		inboundSocket = theInboundSocket;
72  	}
73  
74  
75  	/**
76  	 * Processes an incoming message string and returns the response message
77  	 * string. Message processing consists of parsing the message, finding an
78  	 * appropriate Application and processing the message with it, and encoding
79  	 * the response. Applications are chosen from among those registered using
80  	 * <code>registerApplication</code>. The Parser is obtained from the
81  	 * Connection associated with this Responder.
82  	 */
83  	protected String processMessage(String incomingMessageString)
84  			throws HL7Exception {
85  		
86  		Map<String, Object> metadata = new HashMap<String, Object>();
87  		InetSocketAddress remoteSocketAddress = (InetSocketAddress) inboundSocket.getRemoteSocketAddress();
88  		metadata.put(ApplicationRouter.METADATA_KEY_SENDING_IP, remoteSocketAddress.getAddress().getHostAddress());
89  		
90  		Transportable response = apps.processMessage(new TransportableImpl(incomingMessageString, metadata));
91  		return response.getMessage();
92  	}
93  	
94  //	/**
95  //	 * Logs the given exception and creates an error message to send to the
96  //	 * remote system.
97  //	 * 
98  //	 * @param encoding
99  //	 *            The encoding for the error message. If <code>null</code>, uses
100 //	 *            default encoding
101 //	 */
102 //	public static String logAndMakeErrorMessage(Exception e, Segment inHeader,
103 //			Parser p, String encoding) throws HL7Exception {
104 //		return ApplicationRouterImpl.logAndMakeErrorMessage(e, inHeader, p, encoding);
105 //	}
106 
107 	/**
108 	 * Registers an Application with this Responder. The "Application", in this
109 	 * context, is the software that uses the information in the message. If
110 	 * multiple applications are registered, incoming Message objects will be
111 	 * passed to each one in turn (calling <code>canProcess()</code>) until one
112 	 * of them accepts responsibility for the message. If none of the registered
113 	 * applications can process the message, a DefaultApplication is used, which
114 	 * simply returns an Application Reject message.
115 	 */
116 	void setApplicationRouter(ApplicationRouter router) {
117 		this.apps = router;
118 	}
119 
120 	/**
121 	 * Test code.
122 	 */
123 	@SuppressWarnings({ "unused", "resource" })
124 	public static void main(String args[]) {
125 		if (args.length != 1) {
126 			System.err.println("Usage: DefaultApplication message_file");
127 			System.exit(1);
128 		}
129 
130 		// read test message file ...
131 		try {
132 			File messageFile = new File(args[0]);
133 			Reader in = new BufferedReader(new FileReader(messageFile));
134 			int fileLength = (int) messageFile.length();
135 			char[] cbuf = new char[fileLength];
136 			in.read(cbuf, 0, fileLength);
137 			String messageString = new String(cbuf);
138 
139 			// parse inbound message ...
140 			final Parser parser = new PipeParser();
141 			Message inMessage = null;
142 			try {
143 				inMessage = parser.parse(messageString);
144 			} catch (HL7Exception e) {
145 				e.printStackTrace();
146 			}
147 
148 			// process with responder ...
149 			PipedInputStream initInbound = new PipedInputStream();
150 			PipedOutputStream initOutbound = new PipedOutputStream();
151 			PipedInputStream respInbound = new PipedInputStream(initOutbound);
152 			PipedOutputStream respOutbound = new PipedOutputStream(initInbound);
153 
154 			/*
155 			 * This code won't work with new changes: final Initiator init = new
156 			 * Initiator(parser, new MinLowerLayerProtocol(), initInbound,
157 			 * initOutbound); Responder resp = new Responder(respInbound,
158 			 * respOutbound);
159 			 * 
160 			 * //run the initiator in a separate thread ... final Message
161 			 * inMessCopy = inMessage; Thread initThd = new Thread(new
162 			 * Runnable() { public void run() { try { Message response =
163 			 * init.sendAndReceive(inMessCopy);
164 			 * System.out.println("This is initiator writing response ...");
165 			 * System.out.println(parser.encode(response)); } catch (Exception
166 			 * ie) { if (HL7Exception.class.isAssignableFrom(ie.getClass())) {
167 			 * System.out.println("Error in segment " +
168 			 * ((HL7Exception)ie).getSegmentName() + " field " +
169 			 * ((HL7Exception)ie).getFieldPosition()); } ie.printStackTrace(); }
170 			 * } }); initThd.start();
171 			 * 
172 			 * //process the message we expect from the initiator thread ...
173 			 * System.out.println("Responder is going to respond now ...");
174 			 * resp.processOneMessage();
175 			 */
176 		} catch (Exception e) {
177 			e.printStackTrace();
178 		}
179 
180 	}
181 
182 
183 }