/*
* Created on 3-May-2004
*/
package ca.uhn.hl7v2.protocol.impl;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import ca.uhn.hl7v2.HL7Exception;
import ca.uhn.hl7v2.model.Message;
import ca.uhn.hl7v2.parser.GenericParser;
import ca.uhn.hl7v2.parser.Parser;
import ca.uhn.hl7v2.protocol.Initiator;
import ca.uhn.hl7v2.protocol.Processor;
import ca.uhn.hl7v2.protocol.Transportable;
import ca.uhn.hl7v2.util.Terser;
/**
* Default implementation of <code>Initiator</code>.
*
* @author <a href="mailto:bryan.tripp@uhn.on.ca">Bryan Tripp</a>
* @version $Revision: 1.1 $ updated on $Date: 2007/02/19 02:24:26 $ by $Author: jamesagnew $
*/
public class InitiatorImpl implements Initiator {
private final List myMetadataFields;
private final Parser myParser;
private final Processor myProcessor;
private int myMaxRetries;
private long myRetryInterval;
private long myReceiveTimeout;
/**
* Creates an instance that uses a <code>GenericParser</code>
* @param theProcessor the <code>Processor</code> used to communicate
* with the remote system
*/
public InitiatorImpl(Processor theProcessor) {
myMetadataFields = new ArrayList(20);
myMetadataFields.add("MSH-18"); //add character set by default
myParser = new GenericParser();
myProcessor = theProcessor;
init();
}
/**
* Creates an instance that uses the given <code>Parser</code>
* @param theParser parser to use for parsing and encoding messages
* @param theProcessor the <code>Processor</code> used to communicate
* with the remote system
*/
public InitiatorImpl(Parser theParser, Processor theProcessor) {
myMetadataFields = new ArrayList(20);
myParser = theParser;
myProcessor = theProcessor;
init();
}
private void init() {
myMaxRetries = 3;
myRetryInterval = 3000;
myReceiveTimeout = 10000;
}
/**
* @param theMaxRetries max number of retries for initial message delivery
*/
public void setMaxRetries(int theMaxRetries) {
myMaxRetries = theMaxRetries;
}
public int getMaxRetries() {
return myMaxRetries;
}
/**
* @param theRetryIntervalMillis milliseconds between retries of message delivery
*/
public void setRetryInterval(long theRetryIntervalMillis) {
myRetryInterval = theRetryIntervalMillis;
}
public long getRetryInterval() {
return myRetryInterval;
}
/**
* @param theReceiveTimeout the length of time we wait for responses (defaults
* to 10 seconds)
*/
public void setReceiveTimeout(long theReceiveTimeout) {
myReceiveTimeout = theReceiveTimeout;
}
public long getReceiveTimeout() {
return myReceiveTimeout;
}
/**
* @see ca.uhn.hl7v2.protocol.Initiator#sendAndReceive(ca.uhn.hl7v2.model.Message)
*/
public Message sendAndReceive(Message theMessage) throws HL7Exception {
Terser t = new Terser(theMessage);
String appAckNeeded = t.get("/MSH-16");
String msgId = t.get("/MSH-10");
String messageText = getParser().encode(theMessage);
Map metadata = getMetadata(theMessage);
Transportable out = new TransportableImpl(messageText, metadata);
if (needAck(appAckNeeded)) {
myProcessor.reserve(msgId, getReceiveTimeout());
}
myProcessor.send(out, getMaxRetries(), getRetryInterval());
Message in = null;
if (needAck(appAckNeeded)) {
Transportable received = myProcessor.receive(msgId, getReceiveTimeout());
if (received != null && received.getMessage() != null) {
in = getParser().parse(received.getMessage());
}
}
return in;
}
/**
* @param theAckCode from MSH-16
* @return true if the code indicates that we should wait for an ACK and try
* to return it to the caller
*/
private boolean needAck(String theAckCode) {
boolean need = false;
if (theAckCode == null
|| theAckCode.equals("")
|| theAckCode.equals(Processor.AL)
|| theAckCode.equals(Processor.ER))
{
need = true;
}
return need;
}
private Map getMetadata(Message theMessage) throws HL7Exception {
Map md = new HashMap();
Terser t = new Terser(theMessage);
//snapshot so concurrent changes won't break our iteration
Object[] fields = getMetadataFields().toArray(new Object[0]);
for (int i = 0; i < fields.length; i++) {
String field = fields[i].toString();
String val = t.get(field);
md.put(field, val);
}
return md;
}
/**
* @see ca.uhn.hl7v2.protocol.Initiator#getParser()
*/
public Parser getParser() {
return myParser;
}
/**
* @see ca.uhn.hl7v2.protocol.Initiator#getUnderlyingProcessor()
*/
public Processor getUnderlyingProcessor() {
return myProcessor;
}
/**
* @see ca.uhn.hl7v2.protocol.Initiator#getMetadataFields()
*/
public List getMetadataFields() {
return myMetadataFields;
}
}