Question

May i know how do i loop so i can generate hash code for all the words in the file (.txt) ?
i’m already able to generate single hash code for the file.

the given loop reads and gets out the words in the text document.
but i’m unable to loop the hashkey generation in.

public static void main(String[] args) throws NoSuchAlgorithmException, IOException { 

  JFileChooser chooser=new  JFileChooser();
  int returnVal = chooser.showOpenDialog(null);
  if (returnVal == JFileChooser.APPROVE_OPTION) {
    File f = chooser.getSelectedFile();
  }
  FileInputStream fin = new FileInputStream(chooser.getSelectedFile());
  DataInputStream din = new DataInputStream(fin);    
  BufferedReader br = new BufferedReader(new InputStreamReader(din)); 

  ArrayList<String> list = new ArrayList<String> ();
  MessageDigest md = MessageDigest.getInstance("MD5");

  String currentLine;
  byte[] buf = new byte[8192];

  int len = 0;
  while ((currentLine = br.readLine()) != null) {
    list.add(currentLine);
    md.update(buf, 0, len);
    System.out.println(currentLine);
  }
  br.close();

  byte[] bytes = md.digest();

  StringBuilder sb = new StringBuilder(2 * bytes.length);
  for (byte b : bytes) {
    sb.append("0123456789ABCDEF".charAt((b & 0xF0) >> 4));
    sb.append("0123456789ABCDEF".charAt((b & 0x0F)));
  }
  String hex = sb.toString();

  System.out.println (buf);
  System.out.println(sb);
}

Answer 1

You generate a list of all the lines in the file which you then never seem to use. Maybe you should generate a list of all the words in the file by splitting each line on whitespace;

for (String word : currentLine.split("\\s+")) {
  list.add(word);
}

Then you can use this list to create a list of hashes for each word;

List<byte[]> hashes = new ArrayList<byte[]>(list.size());
for (String word : list) {
  md.reset();
  hashes.add(md.digest(word));
}