19 Troubleshooting

19Copyright © 2007, Oracle. All rights reserved.

Troubleshooting

19-2 Copyright © 2007, Oracle. All rights reserved.

Objectives

After completing this lesson, you should be able to do the following:

• Use JDeveloper and Application Development Framework (ADF) tools for logging and diagnostics

• Test a business service in isolation from views or controllers

• Make use of FileMon, JUnit, and Http Analyzer


Troubleshooting Basics

• Diagnose the problem.

• Request help.

• Create a test case.


Diagnosing the Problem

• Find out where it occurs:– Test the database query and the business services

layer.– Read any exceptions and stack traces.– Set breakpoints in the custom code.

• Examine logs and diagnostic output.

• Strip away complexity.

• Search for similar problems: Google, WebIV, bug.


Requesting Help

Post a topic on the JDeveloper OTN Forum:

• Describe exact steps to reproduce the problem.

• Include a test case, if possible.

• List technologies and product version numbers.

• Provide concrete examples rather than abstract descriptions.

• Include a stack trace, if appropriate.

• Mention troubleshooting steps you have tried and how they affected the problem.


Creating Test Cases

Create the simplest possible application that reproduces the problem:

• Database schema: Use a standard schema, if possible.

• Business service: Remove components and customization.

• Client: Try Business Components (BC) tester, sample client, or basic ADF client.

• Deployment: Try embedded or stand-alone Oracle Application Server Containers for Java EE (OC4J) rather than Application Server.


Logging and Diagnostics

• Java logging

• ADF Logger

• ADF Diagnostics


Java Logging

• Useful for tracing EL evaluation in JavaServer Faces (com.sun.faces).

• Many Java programs use the Java Logging API to produce useful messages.

• You can configure Java logging to produce different levels of logging output:– SEVERE– WARNING– INFO– CONFIG– FINE

– FINER– FINEST– ALL– NONE


Configuring Java Logging

• Configure logging in <jdk_path>\jre\lib\logging.properties.

• Useful settings:– Where to send the output. For example:

– Logging level for different packages. For example:

– Level of messages to a particular output. For example:

com.sun.faces.el.level = FINE

java.util.logging.ConsoleHandler.level = INFO

handlers= java.util.logging.ConsoleHandler


Sending Logger Output to a File

• Set handlers to FileHandler. For example, send output to the console and to a file:

• The log output file is created in your user.home directory.

• File name is java<n>.log (java0.log, java1.log, and so on).

handlers= java.util.logging.ConsoleHandler, java.util.logging.FileHandler


ADF Logger

• ADF classes use the ADF Logger.

• Configuration file, embedded OC4J:– <jdev_home>\jdev\system\oracle.j2ee.xxxxx

\embedded-oc4j\config\j2ee-logging.xml

• Configuration file, stand-alone OC4J:– <oc4j_root>\j2ee\home\config\j2ee-

logging.xml• Contains entries for the different ADF packages:

<logger name="oracle.adf" level="INFO"/> <logger name="oracle.adf.faces" level="INFO"/><logger name="oracle.adf.controller" level="INFO"/><logger name="oracle.bc4j" level="INFO"/>


Using ADF Diagnostics

• Particularly useful for verifying ADF BC SQL statements.

• Outputs detailed information, including:– SQL statements– JDBC connection– Database locks– Configuration property settings– Object creation

• Available in JDeveloper or on the command line


Turning on Diagnostics in JDeveloper


Turning on Diagnostics in OC4J

• Stand-alone OC4J: Start OC4J with the diagnostics option. For example:java –Djbo.debugoutput=console –jar oc4j.jar

• Embedded OC4J:– Shut down the embedded OC4J.– Set the Java option in your client project’s

properties.

• To send diagnostics output to the OC4J logger:– java –Djbo.debugoutput=ADFLogger –jar

oc4j.jar– View the diagnostics on the Log page of

Application Server Control.


Sample Java Clients

• Sample Java clients are useful for testing your business service.

• You can quickly create a sample client for a Web service from the Applications Navigator context menu.

• The client is a generated Java class with code to test your service.

• Client code is not automatically synchronized with changes to your service. You must create a new sample client when you make changes.


Sample Client for Web Service

• The sample client initializes a proxy to the Web service.

• You add custom code to call the Web service operations.

• To create a sample client, select Generate Web Service Proxy in the shortcut menu.

ws.SimpleWebServiceSoapHttpPortClient myPort = new ws.SimpleWebServiceSoapHttpPortClient();System.out.println("calling " + myPort.getEndpoint());// Add your own code hereSystem.out.println(myPort.sampleMethod(“hello”));


Tools and Utilities

• FileMon

• JUnit

• Http Analyzer

• JDeveloper Debugger


Identifying Search Paths with FileMon

• Useful for troubleshooting CLASSPATH problems

• Shows you the path that your running application is looking in for classes and files


Testing Java Code with JUnit

• JUnit is an open-source regression testing framework.

• It is useful for creating tests to verify Java code.

• JDeveloper’s JUnit extension provides wizards for creating test components.

• More information and examples:– SRDemo sample application– Toystore sample application– JDeveloper online documentation– http://www.junit.org


Analyzing HTTP Requests

The Http Analyzer:

• Shows the content of HTTP request and response packets

• Is useful for monitoring Web services


Debugging with JDeveloper

• JDeveloper Debugger is useful for pinpointing problems in your application.

• Set source breakpoints to pinpoint problems in custom code.

• Set exception breakpoints to stop when a particular exception is thrown.

• When a breakpoint is encountered at run time, you can step through code and view values of variables.

• To run a file in debug mode, right-click and select Debug.


Summary

In this lesson, you should have learned how to:

• Diagnose problems, request help, and create test cases to solve a problem in your application

• Use Java and ADF logging, and ADF diagnostics to track down an error

• Create sample clients to eliminate client issues

• Use FileMon, JUnit, Http Analyzer, and JDeveloper Debugger to track down a problem

19 Troubleshooting

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