Array storage

[Stev0]

Hello all,
In class the discussion came up as to saving an array. There is confusion as to whether an array can be saved. The general thought is that an array is an in-memory process only and that the data structure of an array can be saved as a record in a file (binary or ASCII). Can an array be saved directly to a file?
Thank you for clarifying this elementary concept.
Steve

[Chris.Brown.SPE]

Using the toString() function with arrays you can get a string representation of the array, but i have no idea how to get it back from that point. You can always do it by writing a function to save it in your own format and then parse it back to the array when it comes back. Good Luck.

[theonly]

Saving an array as a whole, well you could break the array into a string with spaces then write that into a file. When you want the same array just open the file and combine the string into an array. I hope that make sense.

[bobleny]

I'm new to Java, so I don't know how to do this, but in PHP, I would copy the array contents to a file.

For example, if I have an array like this:
array[0] = "Joe"
array[1] = "Bill"
array[2] = "Jessica"
array[3] = "Amanda"
array[4] = "Tina"

---
Then the text file would look like this:
Joe
Bill
Jessica
Amanda
Tina

---
Then, I simply need to create an array of each line and I'm back to the original array. As of right now, I don't know how to write or read a file....

[DonCash]

Hello bobleny,

To read in the contents of a text file and add each line to an array, use this code:

Code:

FileInputStream in = new FileInputStream("yourFile.txt");
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String strLine;
		
String[] myarray;
myarray = new String[4];
		
for (int i = 0; i < myarray.length; i++){
myarray[i] = br.readLine();
}
		
in.close();

Then you can print out the array content to the console using:

Code:

System.out.println(myarray[0]);
System.out.println(myarray[1]);
System.out.println(myarray[2]);
System.out.println(myarray[3]);

Hope this helps!

[sukatoa]

YOu can also implement it using Scanner class... "reading contents"

regards,
sukatoa

[Eranga]

Here is a simple way that how to write array elements to a text file

Code:

public class ArrayToFile {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        String[] numbers = {"One", "Two", "Three", "Four", "Five"};
        int i = 0;
        
        FileWriter fw = null; 
        
        try {
            fw = new FileWriter("test.txt");
            BufferedWriter out = new BufferedWriter(fw);

            while(i < numbers.length){
                out.write(numbers[i]);
                out.newLine();
                i++;
            }
            out.close();
        } 
        catch (IOException ex) {
            System.out.println(ex.getLocalizedMessage());
        }
    }

}