Preparations for Debugging a
Servlet
In the following scenario, you will incorporate a deliberate error in a servlet, rebuild the Web application, and deploy it so you can start debugging.
Prerequisites
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The Software Deployment Manager (SDM) must be launched before deploying the Web application. |
Procedure
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1. Open the source code of the servlet QuickReservationServlet.java In the J2EE Explorer, double-click J2EE_QuickCarRentalWeb → source → … → QuickReservationServlet.java
2. Display the source code and navigate to the saveActionmethod.
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3. Change the statement:
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String pickupLocation = request.getParameter("pickupLocation");
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as follows:
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String pickupLocation = request.getParameter("pickup");
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As a result of this simple typing error, no valid value is assigned to the pickupLocation variable and the program terminates with an exception.
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4. Save the change.
5. Choose Project -> Rebuild All from the menu.
6. Create an EAR file.
In the J2EE Explorer, right-click the project node J2EE_QuickCarRentalEar and choose Build EAR File from the context menu.
7. Deploy the EAR file.
In the J2EE Explorer, right-click the node J2EE_QuickCarRentalEar → J2EE_QuickCarRentalEar.ear and choose Deploy to J2EE engine from the context menu. (Note: The SDM must be launched for a successful deployment.)
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8. After the successful deployment start the Web application using the following URL:
http://localhost:50000/QuickCarRental
Result
An error message occurs during the execution of the application when you try to store a reservation using the button Add Reservation.
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This means that the error occurs during the call of the saveBooking method, which is called in the servlet method saveAction.
Next step: