Welcome!

Weblogic Authors: Michael Meiner, Michael Bushong, Avi Rosenthal

Related Topics: Weblogic, Eclipse

Weblogic: Article

Configuring Eclipse for Remote Debugging a WebLogic Java Application

A J2EE application deployed in the WebLogic server may be debugged in the Eclipse ID

A J2EE application deployed in the WebLogic server may be debugged in the Eclipse IDE with the remote debugger provided by Eclipse. Without a debugger the error message has to be obtained from the application server error log to debug the application.

With the remote debugger provided by Eclipse, exception breakpoints may be added to the application file to debug. When an application is run in WebLogic and the application generates an error, the application gets suspended and the Eclipse IDE Debug perspective displays the error. In this tutorial we will debug a WebLogic Application Server application in Eclipse.

To debug an application deployed in the WebLogic Server from Eclipse, start the WebLogic Server in debug mode and configure a remote debugging configuration in Eclipse. Next, connect the Eclipse remote debugger to the WebLogic Server and debug applications running in the server. We will develop an example servlet application and deploy the application in WebLogic. First, the servlet is run without any error and subsequently an error is introduced in the servlet to demonstrate the remote debugging feature in Eclipse.

Preliminary Setup
Download the WebLogic 8.1 Application Server and install it. Download the Eclipse 3.0 or Eclipse 3.02 zip file eclipse-SDK-3.0-win32.zip (www.eclipse.org/downloads/index.php) and install it as well.

Developing a WebLogic Application
After installing the WebLogic Server and the Eclipse IDE, develop a servlet application to run and debug in the WebLogic Server. The example servlet application consists of a doGet method, which prints out a String message to the browser. The example servlet, WebLogicServlet.java, is shown in Listing 1.

Create a directory structure for a Web application. Create a WEB-INF directory and a classes directory in the WEB-INF directory. Create a package directory servlets for the example servlet and copy the WebLogicServlet.java file to the servlets directory. Create a web.xml deployment descriptor for the Web application. Copy the web.xml file to the WEB-INF directory. Listing 2 shows the web.xml file.

The example servlet is mapped to URL pattern /weblogic. The structure of the Web application is illustrated below.


/WEB-INF
| |
web.xml classes
|
servlets
|
WebLogicServlet.class
The compiling, packaging, and deploying of the Web application is done in the Eclipse IDE with an Ant build.xml file. Develop an Ant build.xml file that consists of targets to compile the WebLogicServlet.java and package and deploy the webapp.war Web application. Listing 3 shows the build.xml file.

Table 1 shows the properties of the build.xml file. Table 2 shows the file's targets.

Set the debug attribute of the javac task in the build target to true to enable compilation in debug mode. By compiling an application in debug mode the line number, which generates the exception in a WebLogic Server application, gets displayed in the Debug perspective. Create a new project in the Eclipse IDE. Select File>New>Project. The New Project frame gets displayed. In the New Project wizard select Java>Java Project. Click on the Next button. The New Java Project frame gets displayed. In the New Java Project frame specify a Project Name, EclipseWebLogic for example, and click on the Next button. In the Java Settings frame add a source folder to the project with the Add Folder button.

The New Source Folder frame gets displayed. In the New Source Folder frame specify a folder name, src for example. A source folder gets added to the project. A message prompt gets displayed to update the source folder and the output folder. In the New Java Project frame click on the Finish button to create the project. A new project gets added to the Eclipse IDE. Next, select File>Import to import the example servlet source folder to the project. In the Import Select frame select File System and click on the Next button. In the Import File System frame select the src folder and the build.xml file and then click on the Finish button. The servlet source files get added to the project.

Run the build.xml file to compile, package, and deploy the servlet Web application to the WebLogic Server. Right-click on the build.xml file and select Run>Ant Build. The Web application .war file webapp.war gets generated and is deployed to the WebLogic 8.1 Application Server applications directory. Next, start the WebLogic Server with the bin/run script. Invoke the example servlet in a Web browser with the URL http://localhost:7001/webapp/weblogic. The WebLogicServlet runs in the WebLogic Server and the output gets displayed in the browser.

Configuring a Remote Debugging Configuration in Eclipse
To remote debug a WebLogic application in Eclipse start the WebLogic Server in debug mode. Set the WebLogic Server in debug mode by setting the debug options in the startWebLogic batch script file. The debugging provided by WebLogic is based on the Java Platform Debugger Architecture (JPDA). Set the JAVA_OPTS variable as:

set JAVA_OPTS= -Xdebug -Xnoagent
-Xrunjdwp:transport=dt_socket,address=8787,server=y,suspend=n %JAVA_OPTS%

Table 3 shows the different debug parameters. For further explanation of the debug settings refer to the JPDA documentation (http://java.sun.com/j2se/1.4.2/docs/guide/jpda/). To demonstrate the remote debugging feature of Eclipse, add an exception to the WebLogicServlet.java file. For example, add a NullPointerException to the WebLogicServlet.java class. Replace

out.println("Eclipse WebLogic Remote Debugging");

with

String str=null;
out.println(str.toString());

Next, configure a debug configuration for the Eclipse project. Select the Debug option in the Debug option list. The Debug frame gets displayed. In the Debug frame select the Remote Java Application node. Right-click on the node and select New. In the Debug configuration frame specify a name for the Debug configuration. Select the project that is to be debugged. Select the EclipseWebLogic project previously created in the Eclipse IDE. Select the default value for Connection Type. In the Connection Properties, specify localhost as the Host and specify the Port as the port that was specified in the startWebLogic batch script of the WebLogic server, 8787. Click on the Apply button. A remote Java application debug configuration gets added.

Next add exception breakpoints to the WebLogicServlet.java file. To demonstrate the remote debug feature of Eclipse a NullPointerException was added to the WebLogicServlet.java file earlier in this section. To add a breakpoint to the servlet class, Select Run>Add Java Exception Breakpoint. In the Add Java Exception Breakpoint frame select the NullPointerException. The NullPointerException breakpoint gets added to the servlet class. If a NullPointerException is generated in the servlet application in the WebLogic Server, the application gets suspended and the Debug perspective of the Eclipse IDE displays the exception.

Remote Debugging a WebLogic Application
After configuring a debug configuration for the example servlet application deployed in the WebLogic Server, we will debug the servlet application in the Eclipse IDE. Create a webapp.war Web application from the modified (with the NullPointerException) WebLogicServlet.class file with the build.xml file as explained in the "Developing a WebLogic Application" section. Start the WebLogic Server. The server starts in debug mode with the debug options specified in the startWebLogic batch file.

Next, select the EclipseDebug debug configuration in the Debug frame. Click on the Debug button to connect the remote debugger to the WebLogic Server. The Eclipse remote debugger gets connected to the WebLogic Server. Select the Debug Perspective button to display the debug perspective of the Eclipse IDE. In the Debug perspective the remote debugger is shown connected to the WebLogic server at localhost, port 8787. Access the WebLogicServlet in the WebLogic Server with the URL http://localhost:7001/webapp/weblogic. Because the servlet has a NullPointerException, the servlet gets suspended with a NullPointerException in the Debug perspective. The line that produced the exception gets displayed.

The line that throws the exception is the out.println(str.toString()); code line. The servlet application may be debugged with the different debug options listed by selecting Run in the Eclipse IDE.

Summary
In this tutorial a WebLogic application was debugged in the Eclipse IDE. A WebLogic application may also be debugged from another IDE such as JDeveloper.

More Stories By Deepak Vohra

Deepak Vohra is a Sun Certified Java 1.4 Programmer and a Web developer.

More Stories By Ajay Vohra

Ajay Vohra is a senior solutions architect with DataSynapse Inc.

Comments (3) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
Sreedhar 05/18/06 01:15:58 PM EDT

Does any one know how to do remote debug ging in clustered environment??

Neena 03/09/06 05:59:07 PM EST

Do you know how to debug a Clustered WebLogic Environment or where we can get the information on to set up debugging for Cluster?

SYS-CON Brazil News Desk 01/18/06 07:19:38 PM EST

A J2EE application deployed in the WebLogic server may be debugged in the Eclipse IDE with the remote debugger provided by Eclipse. Without a debugger the error message has to be obtained from the application server error log to debug the application.

@ThingsExpo Stories
“In the past year we've seen a lot of stabilization of WebRTC. You can now use it in production with a far greater degree of certainty. A lot of the real developments in the past year have been in things like the data channel, which will enable a whole new type of application," explained Peter Dunkley, Technical Director at Acision, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Events announced today that Windstream, a leading provider of advanced network and cloud communications, has been named “Silver Sponsor” of SYS-CON's 16th International Cloud Expo®, which will take place on June 9–11, 2015, at the Javits Center in New York, NY. Windstream (Nasdaq: WIN), a FORTUNE 500 and S&P 500 company, is a leading provider of advanced network communications, including cloud computing and managed services, to businesses nationwide. The company also offers broadband, phone and digital TV services to consumers primarily in rural areas.
The Internet of Things is not new. Historically, smart businesses have used its basic concept of leveraging data to drive better decision making and have capitalized on those insights to realize additional revenue opportunities. So, what has changed to make the Internet of Things one of the hottest topics in tech? In his session at @ThingsExpo, Chris Gray, Director, Embedded and Internet of Things, discussed the underlying factors that are driving the economics of intelligent systems. Discover how hardware commoditization, the ubiquitous nature of connectivity, and the emergence of Big Data a...

ARMONK, N.Y., Nov. 20, 2014 /PRNewswire/ --  IBM (NYSE: IBM) today announced that it is bringing a greater level of control, security and flexibility to cloud-based application development and delivery with a single-tenant version of Bluemix, IBM's platform-as-a-service. The new platform enables developers to build ap...

SYS-CON Events announced today that IDenticard will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. IDenticard™ is the security division of Brady Corp (NYSE: BRC), a $1.5 billion manufacturer of identification products. We have small-company values with the strength and stability of a major corporation. IDenticard offers local sales, support and service to our customers across the United States and Canada. Our partner network encompasses some 300 of the world's leading systems integrators and security s...
DevOps Summit 2015 New York, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that it is now accepting Keynote Proposals. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to wait for long development cycles that produce software that is obsolete at launch. DevOps may be disruptive, but it is essential.
The major cloud platforms defy a simple, side-by-side analysis. Each of the major IaaS public-cloud platforms offers their own unique strengths and functionality. Options for on-site private cloud are diverse as well, and must be designed and deployed while taking existing legacy architecture and infrastructure into account. Then the reality is that most enterprises are embarking on a hybrid cloud strategy and programs. In this Power Panel at 15th Cloud Expo (http://www.CloudComputingExpo.com), moderated by Ashar Baig, Research Director, Cloud, at Gigaom Research, Nate Gordon, Director of T...
"BSQUARE is in the business of selling software solutions for smart connected devices. It's obvious that IoT has moved from being a technology to being a fundamental part of business, and in the last 18 months people have said let's figure out how to do it and let's put some focus on it, " explained Dave Wagstaff, VP & Chief Architect, at BSQUARE Corporation, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
"People are a lot more knowledgeable about APIs now. There are two types of people who work with APIs - IT people who want to use APIs for something internal and the product managers who want to do something outside APIs for people to connect to them," explained Roberto Medrano, Executive Vice President at SOA Software, in this SYS-CON.tv interview at Cloud Expo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Nigeria has the largest economy in Africa, at more than US$500 billion, and ranks 23rd in the world. A recent re-evaluation of Nigeria's true economic size doubled the previous estimate, and brought it well ahead of South Africa, which is a member (unlike Nigeria) of the G20 club for political as well as economic reasons. Nigeria's economy can be said to be quite diverse from one point of view, but heavily dependent on oil and gas at the same time. Oil and natural gas account for about 15% of Nigera's overall economy, but traditionally represent more than 90% of the country's exports and as...
The Internet of Things is a misnomer. That implies that everything is on the Internet, and that simply should not be - especially for things that are blurring the line between medical devices that stimulate like a pacemaker and quantified self-sensors like a pedometer or pulse tracker. The mesh of things that we manage must be segmented into zones of trust for sensing data, transmitting data, receiving command and control administrative changes, and peer-to-peer mesh messaging. In his session at @ThingsExpo, Ryan Bagnulo, Solution Architect / Software Engineer at SOA Software, focused on desi...
"At our booth we are showing how to provide trust in the Internet of Things. Trust is where everything starts to become secure and trustworthy. Now with the scaling of the Internet of Things it becomes an interesting question – I've heard numbers from 200 billion devices next year up to a trillion in the next 10 to 15 years," explained Johannes Lintzen, Vice President of Sales at Utimaco, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
"For over 25 years we have been working with a lot of enterprise customers and we have seen how companies create applications. And now that we have moved to cloud computing, mobile, social and the Internet of Things, we see that the market needs a new way of creating applications," stated Jesse Shiah, CEO, President and Co-Founder of AgilePoint Inc., in this SYS-CON.tv interview at 15th Cloud Expo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Events announced today that Gridstore™, the leader in hyper-converged infrastructure purpose-built to optimize Microsoft workloads, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Gridstore™ is the leader in hyper-converged infrastructure purpose-built for Microsoft workloads and designed to accelerate applications in virtualized environments. Gridstore’s hyper-converged infrastructure is the industry’s first all flash version of HyperConverged Appliances that include both compute and storag...
Today’s enterprise is being driven by disruptive competitive and human capital requirements to provide enterprise application access through not only desktops, but also mobile devices. To retrofit existing programs across all these devices using traditional programming methods is very costly and time consuming – often prohibitively so. In his session at @ThingsExpo, Jesse Shiah, CEO, President, and Co-Founder of AgilePoint Inc., discussed how you can create applications that run on all mobile devices as well as laptops and desktops using a visual drag-and-drop application – and eForms-buildi...
We certainly live in interesting technological times. And no more interesting than the current competing IoT standards for connectivity. Various standards bodies, approaches, and ecosystems are vying for mindshare and positioning for a competitive edge. It is clear that when the dust settles, we will have new protocols, evolved protocols, that will change the way we interact with devices and infrastructure. We will also have evolved web protocols, like HTTP/2, that will be changing the very core of our infrastructures. At the same time, we have old approaches made new again like micro-services...
Code Halos - aka "digital fingerprints" - are the key organizing principle to understand a) how dumb things become smart and b) how to monetize this dynamic. In his session at @ThingsExpo, Robert Brown, AVP, Center for the Future of Work at Cognizant Technology Solutions, outlined research, analysis and recommendations from his recently published book on this phenomena on the way leading edge organizations like GE and Disney are unlocking the Internet of Things opportunity and what steps your organization should be taking to position itself for the next platform of digital competition.
The 3rd International Internet of @ThingsExpo, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that its Call for Papers is now open. The Internet of Things (IoT) is the biggest idea since the creation of the Worldwide Web more than 20 years ago.
As the Internet of Things unfolds, mobile and wearable devices are blurring the line between physical and digital, integrating ever more closely with our interests, our routines, our daily lives. Contextual computing and smart, sensor-equipped spaces bring the potential to walk through a world that recognizes us and responds accordingly. We become continuous transmitters and receivers of data. In his session at @ThingsExpo, Andrew Bolwell, Director of Innovation for HP's Printing and Personal Systems Group, discussed how key attributes of mobile technology – touch input, sensors, social, and ...
In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect at GE, and Ibrahim Gokcen, who leads GE's advanced IoT analytics, focused on the Internet of Things / Industrial Internet and how to make it operational for business end-users. Learn about the challenges posed by machine and sensor data and how to marry it with enterprise data. They also discussed the tips and tricks to provide the Industrial Internet as an end-user consumable service using Big Data Analytics and Industrial Cloud.