How to assign a String from a text file into integer array for Java?

How to assign a String from a text file into integer array for Java? I had saved the integer array into a text file, but now how can I retrieve all the integer array from the text file without any modification? I want the integer array retrieved same as before it stored into the text file. Below is part of my code:

BufferedWriter f1 = new BufferedWriter(new InputStreamReader(new FileInputStream("Input.txt")));

int a[ ] = yes(test, test.length); //go to yes method,return value to array  
for(int i = 0; i < a.length; i++)  
{  
    f1.write(a[i]);  
}  
    f1.close( );  

BufferedReader f2 = new BufferedReader(new InputStreamReader(new FileInputStream("Input.txt")));  
String src;  
while((src = f2.readLine( )) != null)  
{  
    String[ ] s = src;  
    int a[ ] = Integer.parseInt(s);//same with before it saved  
    ... ...  
}

(incompatible types found)
How to reserve the originality of the integer array(a[ ]) after saved and retrieved from the text file? Thanks!

From stackoverflow

• You need to somehow separate the integers. The simplest solution is to write each one in a separate line. Or use a comma separated list and then use String.split(",")

  ng : Currently he is not writing integers, he is writing characters.

  kgiannakakis : That is what I've suggested. Reformat the way the data are being written.

  ng : Its got nothing to do with format, he is not even writing the valid data.

• The way you have written the characters is totally wrong, you are writing the character representation of the int. Internally this is written as a char. You need to write your integers like so.

  for(int i = 0; i < a.length; i++)
  {
     String value = String.valueOf(a[i]);
     f1.println(value);
  }
  

  This should be compatible with how you are now reading your integers.

• This looks like homework. Anyway, here's my test code:

  // Write integers to a file, each on a different line
  BufferedWriter f1 = new BufferedWriter( new FileWriter( new File( "Input.txt" ) ) );
  int a[] = new int[]{ 17 , 42 , 37 };
  for ( int i = 0 ; i < a.length ; i++ ) {
    f1.write( String.valueOf( a[ i ] ) + "\r\n" );
  }
  f1.close();
  
  // Read integers from a file, assume each value on a different line
  final BufferedReader bufferedReader = new BufferedReader( new FileReader( new File( "Input.txt" ) ) );
  String line;
  final List< Integer > values = new ArrayList< Integer >();
  while ( ( line = bufferedReader.readLine() ) != null ) {
    values.add( Integer.valueOf( line ) );
  }
  bufferedReader.close();
  
  // Convert List elements to array
  final int[] valueArray = new int[ values.size() ];
  int counter = 0;
  for ( int value : values ) {
    valueArray[ counter ] = value;
    counter++;
  }
  
  // Print array values
  for ( int value : valueArray ) {
    System.out.println( "value: |" + value + "|" );
  }
  

  The output is as follows

  value: |17|
  value: |42|
  value: |37|
  

  dhiller : This is a List instance holding Integer objects. Please see the collections framework in java for further information.

  dhiller : Small hint: A List implements the Iterable interface so you can use it in a new for loop.