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Thread: Reading a text file + Nested Loop

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    Junior Member iCurtisIT's Avatar
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    Default Reading a text file + Nested Loop

    Hello. I have asked other questions about this, but keep running into more things I do not understand.

    The above blocks of text (Each Unit), carries on until Unit 13.
    I have the following code, but I keep getting errors. I want the loop to start when it reads the word "Unit" and stop when it reads a "Blank Line".

    I do appreciate anyones help. I am very new to this, and it is causing me major stress and frustration

    Thanks again.


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    Default Re: Reading a text file + Nested Loop

    And how many times have you been told to post your errors. Of if if the code is not providing the desired results, give sample runs and describe what needs to change.

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    Junior Member iCurtisIT's Avatar
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    Default Re: Reading a text file + Nested Loop

    Do you mean this?

    Exception in thread "main" java.util.NoSuchElementException
    	at java.util.Scanner.throwFor(Unknown Source)
    	at java.util.Scanner.next(Unknown Source)
    	at packagename.Task_3.main(Task_3.java:43)

    Line 43 is
    if (inFile.next() == "Unit")

    I am sorry. I didn't realise you wanted that. I just commented saying I got an error in that "Unit" line. Thought that was enough.

    What do you mean give sample runs? :S

    I do appreciate your help. I am trying.

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    Default Re: Reading a text file + Nested Loop

    Yes. It's important for us to see the error to understand the problem and to explain to you what it means so that you don't need us anymore. Otherwise, we're suggesting fixes, you don't know why, and you haven't gotten anything from the experience.

    In this case, from the last line of what you posted, something's going wrong in line 43 of the main() method of the class Task_3 in the package packagename. The something wrong is that there is no element being found for the next() method, like maybe the end of file has been reached or a blank line. You might try fixing this by using the nextLine() method rather than next() to find blank or empty lines. For lines in the text file with multiple 'tokens', use the nextLine() method and split the tokens into a String array using the String.split() method. There are other options, too, but (IMO) this is the easiest.

    You have another flaw with the line you posted, and that is you shouldn't use the comparison operator, '==', to compare Strings. Use the equals() method instead.

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    Super Moderator Norm's Avatar
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    Default Re: Reading a text file + Nested Loop

    Another suggestion: read the String into a variable and then test its contents. The posted code doesn't save what was read so if you want to use it for something, it is gone.
    If you don't understand my answer, don't ignore it, ask a question.

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    Junior Member iCurtisIT's Avatar
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    Default Re: Reading a text file + Nested Loop

    Thank you for your advice. I will try all of the things mentioned and get back to you. I thought learning Spanish was hard, Java is something else.

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    Default Re: Reading a text file + Nested Loop

    Quote Originally Posted by GregBrannon View Post
    array using the String.split() method. There are other options, too, but (IMO) this is the easiest.
    Is there a way of doing it without using an Array?

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    Default Re: Reading a text file + Nested Loop

    Put the String into a Scanner class constructor and use the Scanner class's methods to test for and read the tokens.
    If you don't understand my answer, don't ignore it, ask a question.

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