When standalone client applications (such as Java applications
which access enterprise beans hosted in WebSphere Application Server) have
problems interacting with WebSphere Application Server, it may be useful to
enable tracing for the application. Enabling trace for client programs will
cause the WebSphere Application Server classes used by those applications,
such as naming-service client classes, to generate trace information.
About this task
A common troubleshooting technique is to enable tracing on both
the application server and client applications, and match records according
to timestamp to try to understand where a problem is occurring.
Procedure
- To enable trace for the WebSphere Application Server classes in
a client application, add the system properties shown in the following example
to the startup script or command of the client application. The location
of the output and the classes and detail included in the trace follow the
same rules as for adding trace to WebSphere Application Servers. For example,
trace the standalone client application program named com.ibm.sample.MyClientProgram,
you would enter the following command:
java -DtraceSettingsFile=MyTraceSettings.properties
-Djava.util.logging.manager=com.ibm.ws.bootstrap.WsLogManager
-Djava.util.logging.configureByServer=true com.ibm.samples.MyClientProgram
The file identified by filename must be a properties file placed
in the classpath of the application client or stand-alone process. An example
file is provided in
You cannot use the -DtraceSettingsFile=TraceSettings.properties property
to enable tracing of the ORB component for thin clients. ORB tracing output
for thin clients can be directed by setting com.ibm.CORBA.Debug.Output
= debugOutputFilename parameter in the command line.
The
java.util.logging.manager and java.util.logging.configureByServer system properties
configure Java logging to use a WebSphere Application Server-specific LogManager
class and to use the configuration from the file specified by the traceSettingsFile
property. The default Java Logging properties file, located in the Java Runtime
Environment (JRE), will not be applied.
- You can configure the MyTraceSettings.properties file
to send trace output to a file using the traceFileName property.
Specify one of two options:
- The fully qualified name of an output file. For example, traceFileName=c:\\MyTraceFile.log.
You must specify this property to generate visible output.
- stdout. When specified, output is written to System.out.
- You can also specify a trace string for writing messages with the Trace
String property, Specify a startup trace specification similar
to that available on the server. For your convenience, you can
enter multiple individual trace strings into the trace settings file, one
trace string per line.
Results
Here are the results of using each optional property setting:
- Specify a valid setting for the traceFileName property
without a trace string to write messages to the specified file or System.out only.
- Specify a trace string without a traceFileName property
value to generate no output.
- Specify both a valid traceFileName property and
a trace string to write both message and trace entries to the location specified
in the traceFileName property.