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Thread: Infix calculator problem

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    Default Infix calculator problem[SOLVED]

    Hello everyone I am new here on the forums so first of all hi to everyone .
    I am making a infix calculator and the only problem that i am having is handling the parenthesis . The expression without parenthesis is solved correctly but when it comes to an expression with parenthesis i get exception.

    PROBLEM SOLVED , THANKS FOR THE REPLIES
    Last edited by cubertron; December 3rd, 2011 at 05:16 AM.


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    Default Re: Infix calculator problem

    i get exception
    Please post the full text of the error message.

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    Default Re: Infix calculator problem

    This is the exception message
    Exception in thread "main" java.lang.NullPointerException
    at d8.apply(d8.java:178)
    at d8.eVal(d8.java:146)
    at d8.main(d8.java:241)

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    Default Re: Infix calculator problem

    The error message says the code is trying to use a variable with a null value at line 178.
    Look at line 178, see which variable is null and backtrack in the code to find out why that variable does not have a valid value and change the code so it gets a valid value.

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