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Thread: read and modify a text file

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    Question read and modify a text file

    Good evening \ morning ppl

    i have homework that requires

    "Write a Java program to perform the following:

    Read 5 floating point number and 5 integers from Keyboard.

    Write them to a file with name “dataFile1.txt”

    Read and display them.

    Read and multiply by 2 and write them back to the another file “dataFile2.txt”.

    Read the file “dataFile2.txt” and display the values"

    I did the first part but I have difficulties in doning the second part which is "Read and multiply by 2 and write them back to the another file “dataFile2.txt”."

    Can any one help me


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    Default Re: read and modify a text file

    What are you having problems with?
    Please explain.

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    Default Re: read and modify a text file

    You should probably use a Scanner, or something to read the file.

    It has a nextInt() function already in it.

    However, you should probably keep track of which type is a int and which is a float and where they are. For instance, you could do something like this

    Scanner s;
    try
    {
    s = new Scanner(new File("dataFile2.txt"));
    }

    catch(java.io.FileNotFoundException fnfe)
    {
    System.out.println("File not found.");
    System.exit(1);
    }

    Did you try that already?

    Also, you could try this

    int x;
    float y;

    x = s.nextInt();
    y = s.nextFloat();

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