PK72989: THE INFORMATION IN THE INFORMATION CENTER TO GUIDE A DEVELOPER IN USING A JAVA MANAGEMENT MBEAN IS INADEQUATE

Fixes are available

APAR status

Closed as documentation error.

Error description

The WebSphere Application Server Information Center has a lot of
information related to writing code to interact with the
AdminClient and to write Java Management Beans to get statistics
from the Application Server.  Part of the confusion in the
Information Center is the organization of the information.
But also, how certain statistics work is also not
well-documented. Also, there are two methods for getting this
information:
1. use the J2EE management beans, and request the J2EE
Resources, one of which should be the JMSEndpointStats
2. Use the PerfMBean.
The "Using the JMX interface to develop your own monitoring
application" documents this.
http://publib.boulder.ibm.com/infocenter/wasinfo/v6r1/index.jsp?
topic=/com.ibm.websphere.nd.doc/info/ae/ae/tprf_pmijmx.html
.
In addition there are some typographical errors in the
documentation.
.
This APAR is to address these issues.
1. Address some things that are inaccurate in the Information
Center, such as the coding errors I noted, and the correct
information to access the queue statistics.
.
2. Improve the documentation for the MBean.  To add a
statement in each statistic to state what its object name is.
To improve the examples to make them more useful to someone who
is trying to figure out how to write code to get statistics.
.
3. Document how to access the JMSStats since this was difficult.
The information on how to get the JMSStats from the PerfMBean is
difficult to find.  There is no documentation on how to do
that, and in the list where the PMI data enumerated does not
lst JMSStats in the list of accessible statistics.
.--------------------------------------------------------------
Here are the items that need to be corrected in the
Information Center.
1. There are two errors on this page.
com.ibm.websphere.pmi.stat
Interface WSStats
.
The first is this line of code.
params = new Object[] {jvmMBean, new Boolean(fase)};
I believe fase should be false.
.
The second is that the example code never sets the object
name
ObjectName perfMBean;   // get Perf MBean (MBean type=Perf)
ObjectName jvmMBean;    // get JVM MBean (MBean type=JVM)
It is hinted at that they should be set.
.
3.     The direct path to the PerfMBean to obtain the Queue
stats was obscure.  The link:
http://publib.boulder.ibm.com/infocenter/wasinfo/v6r1/index.jsp?
topic=/com.ibm.websphere.nd.doc/info/ae/ae/rprf_communicationsta
ts.html
gives an incorrect path of Performance Modules > SIB Service >
SIB Messaging Engines > Messaging Engine > Destinations > Queues
to the queue stats.

The correct path, or at least the path that returned the data,
is "SIB Service", "SIB Messaging Engines", <busname>,
"Destinations", "Queues".
.--------------------------------------------------------------
In terms of improving the documentation to make it easier to
get performance statistics from WebSphere AppServer, these
changes are requested.
1. Clarify which MBeans have statistics providers in the
documentation vs. making somone figure this out via code.
It appears that the JMSResource MBean does not implement any
J2EE stats. Using the JSR77 J2EE management beans did not
work.  No statistics providers were available for type
JMSResource, even
though the JMSEndpointStats should be if this is implemented.
For many stats, the statsProvider returns false,
boolean hasStats = ((Boolean)
adminClient.getAttribute(jmsMBean,
"statisticsProvider")).booleanValue();
.
hasStats always is false, because the JMSBean always has a
value of false.
Document what MBeans have statistics providers that are
implemented.
.
2. The example code in
http://publib.boulder.ibm.com/infocenter/wasinfo/v6r1/index.j
sp?topic=/com.ibm.websphere.base.doc/info/aes/ae/rprf_samplecode
apidirect.html
uses the deprecated class
com.ibm.websphere.management.statistics.JVMStats vs. using the
javax.management.j2ee classes and a statisticsprovider.
.
3. Show a more complex example of getting the stats than just
the jvmheapsize in
Using the JMX interface to develop your own monitoring
application
http://publib.boulder.ibm.com/infocenter/wasinfo/v6r1/index.jsp?
topic=/com.ibm.websphere.nd.doc/info/ae/ae/tprf_pmijmx.html
.
4. There was no example on how to traverse the tree returned by
the PerfMBean on a V6 platform.  The examples had quite a bit of
code, but only one method for V6, which did not show how to do
this.
.
5. There is little mention of the steps necesseary if SSL is
required for MBean communication over SSL.  It appears to be
the default. There is only one example that shows how to
configure the SOAP connection for SSL, but even then there was
no discussion of how to import the required keys.
.
6. For the WSStats[] array returned by querying the PerfMBean
using the above path, each element returns a type (with
getStatsType())
of com.ibm.ws.sib.processor.stats.static.QueueStats, which is a
non-existent type.
com.ibm.websphere.pmi.stat.WSStats[] queueStats =
(com.ibm.websphere.pmi.stat.WSStats[])

getAdminClient().invoke(getPerfObjectName(),
"getStatsArray", params, signature);

if (queueStats.length > 0 && queueStats[0] != null) {
System.out.println (queueStats[0].toString());
.
This is the output of the println:
" Stats name=AG_MONITOR_QUEUE,
type=com.ibm.ws.sib.processor.stats.static.QueueStats {}"
.
.------------------------------------------
Here is what information is needed to access the JMSStats.
1. The SIBMessagingEngine MBean can be used to retrieve the
correct stats, to get this to work, the fix for APAR PK59630 is
needed.

2. Another option is to use the server MBean or the perf Mbean.
The "SIB Service" group (as can be seen in the runtime PMI
panels in the Admin console). So something like this...
.
String query = "WebSphere:*,type=Server";
ObjectName queryName = new ObjectName(query);
Set s = adminClient.queryNames(queryName, null);
ObjectName serverMbean = (ObjectName)s.iterator().next();
// Standard JSR-77 stats retrieval.
Stats serverStats = (Stats)adminClient.getAttribute(serverMbean,
"stats");
Statistic[] theStats = serverStats.getStatistics();
... and then refine the results down to the SIB-specific
statistics.

3. Alternatively, to go in via the performance mbean and get
WSStatsobjects. Here is an example to get ME (Messaging Engine)
statistics...
String query = "WebSphere:*,type=Perf";
ObjectName queryName = new ObjectName(query);
Set s = adminClient.queryNames(queryName, null);
ObjectName perfMbean = (ObjectName)s.iterator().next();
ObjectName serverMBean; // obtained in similar manner to
performance bean

// invoke getStatsObject on perfMBean
signature = new String[]
{"javax.management.ObjectName","java.lang.Boolean"};
params = new Object[] {serverMBean, new Boolean(false)};
WSStats wsStats = (WSStats) ac.invoke(serverMBean,
"getStatsObject", params, signature);
WSStats meStats = wsStats.getStats("SIB Service").getStats("SIB
Messaging Engines").getStats (messageEngine);
.

Local fix

Problem summary

****************************************************************
* USERS AFFECTED:  All users of WebSphere Application Server   *
*                  V6.0.2 and above.                           *
****************************************************************
* PROBLEM DESCRIPTION: This APAR is used to improve the        *
*                      javadoc information in the Information  *
*                      Center and to improve the examples to   *
*                      make them more useful to someone who    *
*                      is trying to figure out how to write    *
*                      code to get statistics                  *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
1. There are two errors on the page.
http://publib.boulder.ibm.com/infocenter/wasinfo/v6r1/topic/com.
ibm.websphere.javadoc.doc/public_html/api/com/ibm/websphere/pmi/
stat/WSStats.html

com.ibm.websphere.pmi.stat
Interface WSStats
.
The first is this line of code.
params = new Object[] {jvmMBean, new Boolean(fase)};
fase should be false.
.
The second is that the example code never sets the object
name
ObjectName perfMBean;   // get Perf MBean (MBean type=Perf)
ObjectName jvmMBean;    // get JVM MBean (MBean type=JVM)
It is hinted at that they should be set.

Problem conclusion

The javadoc section of the file has been updated with the
proper example for getting the PerfMBean and JVMMBean and the
corrections in the text.

Temporary fix

Comments

APAR Information

APAR number
PK72989
Reported component name
WEBSPHERE APP S
Reported component ID
5724J0800
Reported release
60W
Status
CLOSED DOC
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2008-09-30
Closed date
2008-12-04
Last modified date
2008-12-04

APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:

Fix information

Applicable component levels

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSEQTP","label":"WebSphere Application Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"6.0","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
29 December 2021

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PK72989: THE INFORMATION IN THE INFORMATION CENTER TO GUIDE A DEVELOPER IN USING A JAVA MANAGEMENT MBEAN IS INADEQUATE

Fixes are available

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APAR status

Closed as documentation error.

Error description

Local fix

Problem summary

Problem conclusion

Temporary fix

Comments

APAR Information

APAR number

Reported component name

Reported component ID

Reported release

Status

PE

HIPER

Special Attention

Submitted date

Closed date

Last modified date

APAR is sysrouted FROM one or more of the following:

APAR is sysrouted TO one or more of the following:

Fix information

Applicable component levels

Document Information

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