ca.uhn.hl7v2.app.Receiver Maven / Gradle / Ivy
/**
* The contents of this file are subject to the Mozilla Public License Version 1.1
* (the "License"); you may not use this file except in compliance with the License.
* You may obtain a copy of the License at http://www.mozilla.org/MPL/
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the
* specific language governing rights and limitations under the License.
*
* The Original Code is "Receiver.java". Description:
* "Listens for incoming messages on a certain input stream, and
* sends them to the appropriate location."
*
* The Initial Developer of the Original Code is University Health Network. Copyright (C)
* 2002. All Rights Reserved.
*
* Contributor(s): _____________.
*
* Alternatively, the contents of this file may be used under the terms of the
* GNU General Public License (the "GPL"), in which case the provisions of the GPL are
* applicable instead of those above. If you wish to allow use of your version of this
* file only under the terms of the GPL and not to allow others to use your version
* of this file under the MPL, indicate your decision by deleting the provisions above
* and replace them with the notice and other provisions required by the GPL License.
* If you do not delete the provisions above, a recipient may use your version of
* this file under either the MPL or the GPL.
*/
package ca.uhn.hl7v2.app;
import java.io.IOException;
import java.net.SocketException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import ca.uhn.hl7v2.concurrent.Service;
import ca.uhn.hl7v2.llp.HL7Reader;
/**
* Listens for incoming messages on a certain input stream, and sends them to
* the appropriate location.
*
* @author Bryan Tripp
*/
public class Receiver extends Service {
private static final Logger log = LoggerFactory.getLogger(Receiver.class);
private ActiveConnection conn;
private HL7Reader in;
/** Creates a new instance of Receiver, associated with the given Connection */
public Receiver(ActiveConnection c, HL7Reader in) {
super("Receiver", c.getExecutorService());
this.conn = c;
this.in = in;
}
@Override
protected void handle() {
try {
String message = in.getMessage();
if (message == null) {
log.debug("Failed to read a message");
} else {
processMessage(message);
}
} catch (SocketException e) {
// This probably means that the client closed the server connection normally
conn.close();
log.info("SocketException: closing Connection, will no longer read messages with this Receiver: " + e.getMessage());
} catch (IOException e) {
conn.close();
log.warn("IOException: closing Connection, will no longer read messages with this Receiver. ", e);
} catch (Exception e) {
log.error("Error while closing connection: ", e);
}
}
/**
* Processes a single incoming message by sending it to the appropriate
* internal location. If an incoming message contains an MSA-2 field, it is
* assumed that this message is meant as a reply to a message that has been
* sent earlier. In this case an attempt is give the message to the object
* that sent the corresponding outbound message. If the message contains an
* MSA-2 but there are no objects that appear to be waiting for it, it is
* discarded and an exception is logged. If the message does not contain an
* MSA-2 field, it is concluded that the message has arrived unsolicited. In
* this case it is sent to the Responder (in a new Thread).
*/
protected void processMessage(String message) {
String ackID = conn.getParser().getAckID(message);
if (ackID == null) {
log.debug("Unsolicited Message Received: {}", message);
getExecutorService().submit(new Grunt(conn, message));
} else {
if (!conn.isRecipientWaiting(ackID, message)) {
log.info("Unexpected Message Received. This message appears to be an acknowledgement (MSA-2 has a value) so it will be ignored: {}", message);
} else {
log.debug("Response Message Received: {}", message);
}
}
}
/** Independent thread for processing a single message */
private class Grunt implements Runnable {
private ActiveConnection conn;
private String m;
public Grunt(ActiveConnection conn, String message) {
this.conn = conn;
this.m = message;
}
public void run() {
try {
String response = conn.getResponder().processMessage(m);
if (response != null) {
conn.getAckWriter().writeMessage(response);
} else {
log.debug("Not responding to incoming message");
}
} catch (Exception e) {
log.error("Error while processing message: ", e);
}
}
}
}