Need to read data from a text file

I need to read data from a text file and create my own hash table out of it. I'm not allowed to use the built in Java class, so how would I go implementing my own reading method and hash table class?

It's not possible to read from a file without using classes from the core API*. You'll have to get clarification from your instructor as to which classes are and are not allowed.
[http://java.sun.com/docs/books/tutorial/essential/io/]
*Unless you write a bunch of JNI code to replicate what the java.io classes are doing.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       

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    hey ppl
    i have a datagrid in my form.i need to read input(fields..sort of a database) from a text file and display its contents in the datagrid.
    how can this  be done.. and also after every few seconds reading event should be re executed.. and that the contents of the datagrid will keep changing as per the changes in the file...
    please help as this is urgent and important.. if possible please provide me with an example code as i am completely new to flex... 
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    It's not possible to read from a file without using classes from the core API*. You'll have to get clarification from your instructor as to which classes are and are not allowed.
    [http://java.sun.com/docs/books/tutorial/essential/io/]
    *Unless you write a bunch of JNI code to replicate what the java.io classes are doing.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       

  • Read data from a text file, one line at a time.

    I need to read data from a text file, and display each line in a String Indicator on Front Panel. It displays each line, but I get Error 4, End Of Line, unless I enter an extra line of data in the file that I don't need. I tried Read From Text File.vi, made by Nat Instr, and it gave the same error.

    The Read from Text File.vi reads data from a text file line by line until the user stops the VI manually with the Stop button on the front panel, or until an error (such as "Error 4, End of file") occurs. If an error occurs, the Simple Error Handler.vi pops up a dialog that tells you which error occurred.
    The Read from Text File.vi uses a while loop, but if you knew how many lines you wanted to read, you could replace the while loop with a for loop set to read that many lines from the file.
    If you need something more dynamic because the number of lines in your files vary, then you could change the code of the Read from Text File.vi to the expect "Error 4, End of file" and handle it appropriately. This would require unbundling the error cluster that comes fro
    m the Read File function with the Unbundle By Name function, so that you can expose the individual error "status" and error "code" values stored in the cluster. If the value of the error "code" is 4, then you can change the error "status" from true to false, and you can rebundle the cluster with the Bundle by Name function. Setting the error "status" to false instructs the Simple Error Handler to ignore the error. Otherwise, pass the original error cluster to the Simple Error Handler.vi, so that you can see what the error is.
    Of course, if you're not interested in what the errors are, you could just remove the Simple Error Handler.vi, but then you wouldn't see any error messages.
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    Dieter
    Dieter Schweiss
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  • How do you read data from a text file into a JTextArea?

    I'm working on a blogging program and I need to add data from a text file named messages.txt into a JTextArea named messages. How do I go about doing this?

    Student_Coder wrote:
    1) Read the file messages.txt into a String
    2) Initialize messages with the String as the textSwing text components are designed to use Unix-style linefeeds (\n) as line separators. If the text file happens to use a different style, like DOS's carriage-return+linefeed (\r\n), it needs to be converted. The read() method does that, and it saves the info about the line separator style in the Document so the write() method can re-convert it.
    lethalwire wrote:
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    http://java.sun.com/docs/books/tutorial/uiswing/components/editorpane.html
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  • Need to read data from pipe separated file using POJO?

    Hi,
    I need to read data from pipe separated file using POJO.
    There is config.properties file which consists of the
    data mapping.
    Can you help me with sample code or help?
    Regards
    Regards
    Taton
    Edited by: Taton on Mar 7, 2009 4:41 PM

    It's not possible to read from a file without using classes from the core API*. You'll have to get clarification from your instructor as to which classes are and are not allowed.
    [http://java.sun.com/docs/books/tutorial/essential/io/]
    *Unless you write a bunch of JNI code to replicate what the java.io classes are doing.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       

  • Reading Data From A Text File via AppleScript

    Here is my question. I have a text file I need to read data from....this is what the text file looks like opened in text editor:
    "SLUG
    , 06/16/06, APPLE COMPUTER INC , 69x8.50, jondnotin
    now what I need to do is get the 69 and the 8.50 as seperate variables...now every file that is going to be read is setup the same with different information but the data type is the same and in the same order. So what syntax do I need to read this file and set thoes two numbers to variables? Thanks!
    PowerMac G5, iBook G4, Intel MacMini, PowerMac G3 B&W, iMac DV Blueberry   Mac OS X (10.4.7)  

    Hello
    You where right for the file structure.
    I think that it is a complementary reason to locate the data whithout assuming that it sit in paragraph x or y.
    The trailing script get rid of that and allow to grab values from a file containing more than a single entry.
    --[SCRIPT]
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    set {oTID, AppleScript's text item delimiters, texte} to {AppleScript's text item delimiters, d, t}
    set {texte, AppleScript's text item delimiters} to {text item 2 of texte, ","}
    set {texte, AppleScript's text item delimiters} to {text item 1 of texte, "x"}
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    -- -+-+-+-+-+-+-+-
    --[/SCRIPT]
    Yvan KOENIG (from FRANCE vendredi 8 septembre 2006 20:38:46)

  • Reading data from a text file but can't use the data outside of the function.

    I am trying to load a variable from data in a text file.
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    I need to use the variable data outside of the function.
    Does anyone have any suggestions to work around this issue?
    This is the actionscript code i'm using.
    var pathVars= new LoadVars();
    pathVars.onLoad=function(ok) {
    if(ok)
    trace("Loading");
    path_var=pathVars.path;
    trace("This is within the function "+path_var);
    pathVar0="This is within the function... "+path_var;
    Yet the path_var is available here fine.
    pathVars.load("mypath.txt");
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    The external traces are being executed before the file is
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  • Reading data from a text file into PAS - Dimension member names truncated

    Hi,
    I created a procedure to dump variables and data into a text file to load into another model. I used a semicolon as a field seperator.
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    Lungile

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  • Reading data from a text file

    Okay so basically i need to read some text from a file, and display it in a JTextArea. My problem is that when i read the data and display it, its all in one big long line. e.g:
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    Hi
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    Hi
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    HiHiHiHi
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                             BufferedReader buffer = new BufferedReader(reader);
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                             String aa = "";
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    Hii , I think this will help you ,,,
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    import java.io.*;
    import java.util.*;
       class Test5   extends JFrame
            JPanel mainPane;
            JButton doTestBtn = new JButton("Press");
            JTextArea show = new JTextArea(6,6);
            JFileChooser choose = new  JFileChooser();
            public Test5()
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                 gl.setHgap(10);
                 gl.setVgap(10); 
                 mainPane = new JPanel();
                 JPanel  side1 = new  JPanel();
                 JPanel  side2 = new  JPanel();
                 mainPane.add(side1);
                 mainPane.add(side2);
                 side1.add(doTestBtn);
                 side1.add(show);
                 doTestBtn.addActionListener(new ActionListener()
                     public void actionPerformed(ActionEvent e)
                          doTestBtnAction();
            private void doTestBtnAction()
                try
                   int tt =  choose.showOpenDialog(Test5.this);
                   if(tt == JFileChooser.APPROVE_OPTION )
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                      FileReader reader = new FileReader(file);
                      BufferedReader buffer = new BufferedReader(reader);
                          String ss;
                          String aa = "";
                          while((ss = buffer.readLine()) !=null)
                                  aa = aa + ss;
                      show.append(aa);
                      reader.close();
               }catch(IOException ex)
            private void createGUI()
                getContentPane().add(mainPane);
                setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                setSize(200,100);
                pack();
                setVisible(true);
           private static void createAndShowGUI()
              Test5 rn = new Test5();
               rn.createGUI();
           public static void main(String[] args)
            javax.swing.SwingUtilities.invokeLater(new Runnable()
                public void run()
                    createAndShowGUI();
       }Thanks ,
    sb

  • Shell scripts to read data from a text file and to load it into a table

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  • How to read data from a text file

    I have saved a text file on my hard drive, and would like to read the file. Once read I would like to copy it to another file. I think I am suppose to use the BufferedReader, and FileReader classes. I am not sure what sequence to follow in order to do this. Could some one give me some feed back on what is needed, and in what sequence to perform this task?

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  • Reading data from a text file in to an array

    Ok nobody tell me to search forums, read books, point me to the tutorials, i have done all that and still don't get it. so can some one help me write some code. I would like to read text from a file into an array. The array name is VehilcleList. Simplest was possible would be great. I dont want to use redirection, preferably using the filereader and filewriter class i imagine.

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                BufferedReader buf = new BufferedReader(new FileReader(file));
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                    ArrayList params = new ArrayList();
                    while (tk.hasMoreElements()) {
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  • Reading data from a text file into a JTextField

    So I am writing a program that will write to and read from a large database. I was hoping to allow a graphical interface for the reading of the data, but I keep getting an error;
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    Try something like this for putting the text in a control:
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    import javax.swing.JPanel;
    import javax.swing.JTextArea;
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        jt.append("\n\r"+s[1]);
        jt.append("\n\r"+s[2]);
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      public static void main(String[] args) {
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  • Read data from a text file

    I want to read a file from my forms using TEXT_IO

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    text_io.fopen(:PATH,'R')
    text_io.is_open(M_archsal)
    text_io.get_line(M_ArchSal,line) ;
    text_io.fclose(M_ArchSal) ;

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