Example using of getMessage(s) with JMS error queues?

Question

Hi,
I'm cobbling together various tools for easier management of replaying messages left in error queues and the likes, and whilst I've got messages being moved around the place on demand, I can't make any progress using getMessage() and getMessages() to print out vital statistics of a message / all the messages in a queue, including hopefully ripping out excerts of the XML payload in them. Can someone provide / point me to an example of these being in use? I can get a successful execution of getMessages() but am usure what to really do next with the object returned, how to iterate through and such.
Thanks
Chris.

Answer 1

Hi Chris,
There are open source solutions for message management.  In particular, you might want to investigate Hermes:
http://blogs.oracle.com/jamesbayer/2008/01/hermes_jms_open_source_jms_con.html
As for browsing messages via getMessages(), here's a code snippet.  Note that one should never attempt to get too many messages at a time via "getNext()" -- instead call getNext() multiple times.  Otherwise, if there are too many messages, the client or server might run out of memory.
# create a cursor to get all the messages in the queue
# by passing ‘true’ for selector expression, 
# and long value for cursor timeout
cursor1=cmo.getMessages(‘true’,9999999)
# get the next 5 messages starting from the cursor’s
# current end position
# this will adjust the cursor’s current start position and
# end position “forwards” by 5
msgs = cmo.getNext(cursor1, 5)
# print all the messages’ contents
print msgs
# get 3 messages upto the cursor’s current start position
# this will adjust the cursor’s current start and end position backwards by 3
# this will the current position of the message by 1
msgs = cmo.getPrevious(cursor1, 3)
# print all the messages’ contents
print msgs
Finally, here's code based on public APIs that can help with exporting messages to a file.   It uses Java, not WLST. I haven't tested it personally.  I'm not sure if there's away to do this in WLST.
  * pseudo code for JMS Message Export operation based on
  * current implementation in the Administration Console
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.OutputStreamWriter;
  import java.io.BufferedWriter;
  import java.io.Writer;
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Collection;
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  import org.w3c.dom.Node;
  import weblogic.apache.xerces.dom.DocumentImpl;
  import weblogic.apache.xml.serialize.OutputFormat;
  import weblogic.apache.xml.serialize.XMLSerializer; 
  import weblogic.management.runtime.JMSDestinationRuntimeMBean;
  import weblogic.management.runtime.JMSDurableSubscriberRuntimeMBean;
  import weblogic.management.runtime.JMSMessageManagementRuntimeMBean;
  import javax.management.openmbean.CompositeData;
  import weblogic.jms.extensions.JMSMessageInfo;
  import weblogic.jms.extensions.WLMessage;
  import weblogic.messaging.kernel.Cursor;
  public void exportMessages(
    String fileName,
    JMSDestinationRuntimeMBean destination,
    /* or JMSDurableSubscriberRuntimeMBean durableSubscriber */,
    String messageSelector) throws Exception {
    BufferedWriter bw = null;
    try {
      File selectedFile = new File(file);
      if (destination == null /* or durableSubscriber == null */) {
        throw new IllegalArgumentException("A valid destination runtime or durableSubscriber runtime mbean must be specified");
      JMSMessageManagementRuntimeMBean runtime = (JMSMessageManagementRuntimeMBean) destination /* durableSubscriber */;
      bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file),"UTF-8"));
      String xmlDeclaration = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>";
      String exportStart = "<JMSMessageExport>";
      final String exportEnd = "</JMSMessageExport>";
      final String indent = "    ";
      bw.write(xmlDeclaration);
      bw.newLine();
      bw.write(exportStart);
      bw.newLine();
      bw.newLine();
      bw.write(indent);
      CompositeData[] messageInfos = null;
      OutputFormat of = new OutputFormat();
      of.setIndenting(true);
      of.setLineSeparator("\n"+indent);
      of.setOmitXMLDeclaration(true);
      XMLSerializer ser = getXMLSerializer(bw, of);
      String cursor = JMSUtils.getJMSMessageCursor(runtime, selector,0);
      while ((messageInfos = runtime.getNext(cursor,new Integer(20))) != null) {
        for (int i = 0; i < messageInfos.length; i++) {
          JMSMessageInfo mhi = new JMSMessageInfo(messageInfos);
Long mhiHandle = mhi.getHandle();
CompositeData m = runtime.getMessage(cursor, mhiHandle);
// need to get the message with body
JMSMessageInfo mbi = new JMSMessageInfo(m);
WLMessage message = mbi.getMessage();
ser.serialize(message.getJMSMessageDocument());
messageInfos[i] = null;
bw.newLine();
bw.write(exportEnd);
bw.flush();
bw.close();
runtime.closeCursor(cursor);
LOG.success("jms exportmessage success");
} catch (Exception e) {
try {
if(bw != null)
bw.close();
} catch (IOException ioe) { }
LOG.error(e);
LOG.error("jms exportmessage error");
throw(e);
LOG.success("jms exportmessage success");
private XMLSerializer getXMLSerializer(
Writer writer,
OutputFormat of) {
return new XMLSerializer(writer, of) {
protected void printText(
char[] chars,
int start,
int length,
boolean preserveSpace,
boolean unescaped) throws IOException {
super.printText(chars,start,length,true,unescaped);
protected void printText(
String text,
boolean preserveSpace,
boolean unescaped ) throws IOException {
super.printText(text,true,unescaped);
public static String getJMSMessageCursor(
JMSMessageManagementRuntimeMBean runtime,
String selector,
int cursorTimeout) throws weblogic.management.ManagementException
return runtime.getMessages(
selector,
new Integer(cursorTimeout),
new Integer(Cursor.ALL));
Hope this helps,
Tom