Debugging Portal Applications

Debugging Portal Applications Applies to: SAP NetWeaver Portal, and developers of portal applications Summary NetWeaver Developer Studio and the AS Java provide tools for helping you debug your applications. This document provides the very basics on starting to debug applications, and provides a short, simple but clear example on how the debugging tools can be used. Author: Daniel Wroblewski Company: SAP AG Created on: 18 July 2007 Author Bio Daniel Wroblewski is an information developer for SAP, focusing on documentation for portal developers. He has been a developer ever since writing assembler code for the new Apple Macintosh in 1985 (that was cool), and was a developer for Deutsche Bank (Java, VB). He plays center for the SAP Labs Israel basketball team. 2007 SAP AG 1

Table of Contents Overview... 3 Collecting Required Information... 4 Message Server Port... 5 Debug Port... 6 Enabling Debugging... 9 Setting the AS Java... 10 Starting Debugging... 12 Debugging... 14 Set Breakpoints... 14 Inspect Variables... 15 Add Watches... 16 Example... 17 Open Portal Project... 18 Start Debugging... 19 Run the Application... 21 Related Content... 23 Copyright... 24 2007 SAP AG 2

Overview The debugging tools of the AS Java and NetWeaver Developer Studio can help a lot in locating problems with your applications. The following are basic instructions for debugging portal applications. Also provided is a small example of how a simple NullPointerException can be diagnosed using debugging. 2007 SAP AG 3

Collecting Required Information To use debugging, you will need to know the following information: Server Name: The host name for calling the portal in a browser Server Port: The port number for calling the portal in a browser Message Server Port: The port number for calling the AS Java engine, for example, from within the IDE Debug Port: The port number when starting debugging 2007 SAP AG 4

Message Server Port To find the message server port: 1. Launch the AS Java home page by entering in your browser the URL http://<server>:<port>/ (the same as the main portal URL without the irj). 2. Click System Information. Information about the AS Java, such as the server name, instances and ports numbers, is displayed. The message server port is displayed in the upper left. 2007 SAP AG 5

Debug Port 1. Launch the Config Tool by double-clicking configtool.bat (located in the C:\usr\sap\<system ID>\<instance ID>\j2ee\configtool directory). 2007 SAP AG 6

2. Click. The following is displayed: 2007 SAP AG 7

3. Navigate to cluster_data, and click Propertysheet. A table of properties is displayed. The debug port is listed under DebugPort. Note: You can also see the debug mode in the J2EE Engine view of the NetWeaver Developer Studio (below), as well as from the Servers Debug tab when clicking on the instance in the Config Tool. 2007 SAP AG 8

Enabling Debugging 1. Launch the Config Tool by double-clicking configtool.bat (located in the C:\usr\sap\<system ID>\<instance ID>\j2ee\configtool directory). 2. Click on the instance, and select the Servers Debug tab. 3. Make sure the debuggable and Enabled debug mode checkboxes are selected. 4. Save your changes, and restart the server. 2007 SAP AG 9

Setting the AS Java 1. In NetWeaver Developer Studio, select the menu item Window Preferences. 2. Click SAP J2EE Engine, and enter the portal server and message port. 3. Click OK. 4. Open up the J2EE Engine view by navigating to Windows Show View Other, and selecting J2EE J2EE Engine. 2007 SAP AG 10

5. Click to refresh the view. You should now see the server you specified in the Preferences window, with the colors of the nodes indicating the server s status. The current debug mode and port are shown at right. 2007 SAP AG 11

Starting Debugging Before starting to debug, make sure the current version of your project is deployed on the server. 1. Select debugging by either: Selecting Debug under the Debug icon. Selecting Run Debug in the menu. 2007 SAP AG 12

The Debug perspective is opened, and the configuration window is displayed. 2. Select Remote Java Application, click New, and set the following: Project: Select the project that you want to debug. Make sure its most recent version is deployed to the server on which you are debugging. Server: The server on which you are debugging. Debug Port: The debug port of the server. 3. Click Debug. You are now ready to debug. 2007 SAP AG 13

Debugging When debugging, you set breakpoints and watches in the portal component class files, and then run your portal component by navigating in the portal to an iview from your portal component. The portal component pauses when it hits a breakpoint, and the Debug view shows where you are in the component. You can step over or into your code, and inspect variables, functions and expressions. Set Breakpoints 1. Make sure the class file that you want to debug is open. You can open it from Enterprise Portal perspective before debugging. 2. Set a breakpoint by double-clicking at the start of the line. Below, a breakpoint is set on the first line of code in the docontent() method: 2007 SAP AG 14

Inspect Variables When the debugger has stopped at a breakpoint, you can inspect all the local variables, in the Variables window. The variables in the window are those defined in the docontent() method up to the breakpoint. 2007 SAP AG 15

Add Watches You specify variables, expressions and functions to a watch list to help you monitor them. The watch list is shown in the Expressions window. 2007 SAP AG 16

Example I have written a test portal component (HelloWorldProject.testLink) that takes a parameter with a navigation target and creates a link from it. The component tests to see if the parameter starts with the string pcd but, of course, if the parameter is null, the component will crash. The code is as follows: public void docontent(iportalcomponentrequest request, IPortalComponentResponse response) { String target = request.getparameter("mytarget"); if (target.startswith("pcd")) { response.write("starts With PCD<BR>"); } } // Rest of code And the iview displays the following when no parameter is sent. The exception is caught by the Portal Runtime. At first, I do not know why it crashes (and I did not provide any exception handling for the sake of this example). So I choose to debug. In this example, I assume that debug mode is turned on for the server. To turn on debug mode, see Enabling Debugging. 2007 SAP AG 17

Open Portal Project Open the portal project that you want to debug, and open the Java editor for the class file that contains the code to debug. The following shows the HelloWorldProject, with the testlink class that contains the code to debug. The J2EE Engine view is shown at the bottom right. 2007 SAP AG 18

Start Debugging 1. Click Run Debug. 2. Select Remote Java Application, and click New. 3. Enter HelloWorldProject for the project, and enter the server and port. 2007 SAP AG 19

4. Click Debug. The Debug perspective opens. A list of threads is displayed in upper left, and windows for displaying breakpoints and watches are displayed in the upper right. My code is also displayed in the middle. 5. Create a breakpoint for the first line in the docontent() method. 2007 SAP AG 20

Run the Application 1. Now I open the portal and run my iview. As soon as I click on the link to my iview (testlink), the debugger in the NetWeaver Developer Studio comes to life, the Debug perspective opens, and the execution stops at my breakpoint. The line is highlighted and an arrow is displayed next to the line. 2. I step through the first statement, by clicking Run Step Over or pressing F6. 2007 SAP AG 21

3. I check the variables, and notice that target is null. 4. I step through the next statement, and the component crashes. At the very least, I learn the statement that caused the crash. I can also check the log at this point and see that a NullPointerException caused the problem. #1.5#000BCDDCE9DE00700000000800000E2C00043584CF3F6D20#1184744435504#com.sap.portal.portal#sap.com/irj#com.sap.portal.portal#Administr ator#35#####thread[prt-async 3,5,PRT-Async]##0#0#Error#1#/System/Server#Java###Exception ID:07:40_18/07/07_0005_4070150 [EXCEPTION] {0}#1#com.sapportals.portal.prt.component.PortalComponentException: Error in service call of Portal Component Component : pcd:portal_content/danielcontent/danrole/testlink Component class : testlink User : Administrator at com.sapportals.portal.prt.core.portalrequestmanager.handleportalcomponentexception(portalrequestmanager.java:969) at com.sapportals.portal.prt.core.portalrequestmanager.callportalcomponent(portalrequestmanager.java:343) at com.sapportals.portal.prt.core.portalrequestmanager.dispatchrequest(portalrequestmanager.java:136) at com.sapportals.portal.prt.core.portalrequestmanager.dispatchrequest(portalrequestmanager.java:189) at com.sapportals.portal.prt.core.async.asyncportalcomponentresponse.include(asyncportalcomponentresponse.java:355) at com.sapportals.portal.prt.core.async.asyncportalcomponentresponse.include(asyncportalcomponentresponse.java:310) at com.sapportals.portal.navigation.workareaiview.docontent(workareaiview.java:169) at com.sapportals.portal.prt.component.abstractportalcomponent.servicedeprecated(abstractportalcomponent.java:209) at com.sapportals.portal.prt.component.abstractportalcomponent.service(abstractportalcomponent.java:114) at com.sapportals.portal.prt.core.portalrequestmanager.callportalcomponent(portalrequestmanager.java:328) at com.sapportals.portal.prt.core.portalrequestmanager.dispatchrequest(portalrequestmanager.java:136) at com.sapportals.portal.prt.core.async.asyncincluderunnable$1$dodispatchrequest.run(asyncincluderunnable.java:377) at java.security.accesscontroller.doprivileged(native Method) at com.sapportals.portal.prt.core.async.asyncincluderunnable.run(asyncincluderunnable.java:390) at com.sapportals.portal.prt.core.async.threadcontextrunnable.run(threadcontextrunnable.java:164) at EDU.oswego.cs.dl.util.concurrent.PooledExecutor$Worker.run(PooledExecutor.java:729) at java.lang.thread.run(thread.java:534) Caused by: java.lang.nullpointerexception at testlink.docontent(testlink.java:16) at com.sapportals.portal.prt.component.abstractportalcomponent.servicedeprecated(abstractportalcomponent.java:209) at com.sapportals.portal.prt.component.abstractportalcomponent.service(abstractportalcomponent.java:114) at com.sapportals.portal.prt.core.portalrequestmanager.callportalcomponent(portalrequestmanager.java:328)... 15 more 2007 SAP AG 22

Related Content Debugging J2EE Applications Debugging Tools: Log Watch, Navigation Reporter and Navigation Debugger (SAP NetWeaver 7.0 only) 2007 SAP AG 23

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