Exercise 7: Better Form and Action Handling : Struts « J2EE « Java
Exercise 7: Better Form and Action Handling
/*
First edition copyright 2004 ObjectSource LLC. All rights reserved.
This training material and the accompanying lab exercises were prepared
by Srikanth Shenoy for ObjectSource LLC.
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*/
/*
Business Objectives:
The following business objectives will be met at the end of this exercise:
1. Split customer form into multiple pages
2. Prevent the customer from going back and resubmitting and getting a database error.
3. Better Exception handling in the system
Technical Objectives for this exercise:
The technical objectives of this exercise is to learn how to:
19. To fix the bug: when Enter key is pressed in the Customer Search Form, a blank page is shown
20. Use DispatchAction
21. See how things work without exception handling mechanism
22. Provide exception handling mechanism (DuplicateCustomerException)
23. Create custom exception handlers
24. Provide Global exception handling mechanism with JSP
25. Create base ActionForm and Action Classes and use them
26. Create multipage forms. (Expln Only)
27. Handle Duplicate Form Submissions for CustomerForm (Expln Only)
28. Use DynaActionForm for CustomerSearchForm (Expln Only)
Default enter does not do search in Customer Search Form
2. Using DispatchAction
a. Create two methods Create and Edit (notice the case) in ShowCustomerAction so that each
method taking exactly the same input parameters as the execute method.
b. Add appropriate code into each of these methods
c. Comment (or delete) the execute method
1. When Enter key is pressed in the Customer Search Form, a blank page is shown
a. This happens because the CustomerSearchAction performs the search only if serch.x or search.y
are not null. Remove the if condition and it will work for enter key
........
*/
// when I try to deploy the exercise07.jar, some exceptions are printed
/*
SEVERE: Exception sending context initialized event to listener instance of clas
s struts.example.util.ApplicationScopeInit
java.lang.NullPointerException
at java.util.Properties$LineReader.readLine(Properties.java:365)
at java.util.Properties.load(Properties.java:293)
at struts.example.util.ApplicationScopeInit.contextInitialized(Unknown S
ource)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContex
t.java:3637)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4
073)
*/
struts-training.zip( 26,264 k)
