Getting Errors when Clicking on Button

I am new to GWT and I am having trouble with a button causing a lot of errors. I am开发者_开发技巧 posting my class and the errors I am getting. I rather provide all the information than just talk about the problem. I always happens when I click on the button.

I am hoping someone sees the problem based on experience just by glancing at the error and help me figure out what I am doing wrong.

Thank you

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Caused by: java.lang.NullPointerException: null at com.timesheet.tmproject.client.panels.WelcomePanel.completeTransact(WelcomePanel.java:99)

Some variable on line 99 of your WelcomePanel is null.

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Java exceptions stacks always follows GWT exception stacks. When you get some exceptions in GWT, don't worry, just scroll down a little bit, then you'll find what you want.