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Resolving Excel Export I/O Stream Error/Fatal Error Issue

Problem:     Fatal Application Error while exporting search results data into an excel sheet. Root Cause for the Issue is: The Root Cause of the issue is Because of using the global (Instance) variables instead of using the method variables inside the class for writing the data to the excel file. In Struts 1.1/1.2 the Action class behaves like singleton. There will be only one instance of the action for all the incoming requests. So whenever we try to build our logic using the instance variables (The variables which we are defining at the top of the class outside the method area) instead of local variables (or method variables), we will face data inconsistency issues. If we are using this kind of variables for IO operations then we will be ending with Stream errors (like the one we faced in one of our application recently). In the case of our (XYZ) application, there was a call to flushRows(100) function on

Disabled Form Fields Strange Behavior

Disabled form fields of html will not get the values (or will get null) after submitting the Form:  Code like below for the input form fields in HTML will generate the disabled field. Disabled field is the one which is not editable, not focusable, won’t get tab navigation, and can’t select the field. These are the characteristics of the disabled form field. We can apply this attribute on all input fields, buttons, select box, etc.  Please find the code below: <input type=”text” name=”accountNumber” value=”123455” disabled=”disabled”   /> The above code will generate the disabled text field where we can’t be able to edit and select the field. Characteristics of Disabled form fields: 1)    Disabled form field cannot be focusable, i.e. you cannot focus the field. 2)    Disabled fields are non-editable. 3)    Disabled fields will not be submitted when submission of form happens or when we will click on ‘Submit’ button. 4)    Disabled fields will give n

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Useful Java Debugging Tips with Eclipse

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In this tutorial we will see about debugging java applications using Eclipse. Debugging helps us to identify and fix defects in the application. We will focus on run-time issues and not compile time errors. There are command line debuggers like gdb available. In this tutorial we will focus on GUI based debugger and we take our favorite IDE Eclipse to run through the tutorial. Though we say Eclipse, the points are mostly generic and is suitable for debugging using most of the IDEs like NetBeans too. Do not use  System.out.println  as a tool to debug. Enable detailed log level of all the components involved. Use a log analyzer to read logs. 1. Conditional Breakpoint Hope we know how to add a breakpoint. If not, just click on the left pane (just before the line number) and a breakpoint will be created. In debug perspective, ‘Breakpoints’ view will list the breakpoint created. We can add a boolean condition to it. That is, the breakpoint will be activated an