Question

I’m trying to find a string within the directory C:\ which is currently hardcoded. Within this C:\ directory, I’m looking to recursively find the inputted string (inputString) within the root/and subdirectories and finally output the names of the files containing those strings.

I hope the above clarifies my initial question

I currently have assess.java:

import javax.swing.JFrame;

/* Notes: Event - user clicking button, moving mouse
 *  EventHandler - code that response to users action
 * 
 */

class assess {
    public static void main(String args[]){

        assesshelper assessment1 = new assesshelper();
        assessment1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
        assessment1.setSize(500,500); // set size of window
        assessment1.setVisible(true);
    }
}

and
assesshelper.java

import java.awt.FlowLayout; // orientation of screen
import javax.swing.JFrame; // JFrame all basic windows features (min/maximize), title
import javax.swing.JTextField; // Typing text
import javax.swing.JLabel; // output text / images


public class assesshelper extends JFrame {

    private JLabel item1;

    private JTextField theUrl;

    public assesshelper(){ // anything within assesshelper is within window
        super("Assess"); // title of window
        setLayout(new FlowLayout()); // gives us default label

        //item1
        item1 = new JLabel("Welcome!");
        add(item1); // add item1 to the screen


        String setDir = "C:/";
        JTextField inputString = new JTextField();

        inputString.setText("ENTER DIR TO PROCESS");
        /// BEGIN SEARCHING FOR INPUTTED STRING HERE WITHIN ROOT/SUBDIRECTORIES, OUTPUT FILE NAMES CONTAINING STRING

        add(inputString);

    }

}

How do I recursively search for the value of inputString within the directory set by setDir?

(Java-newbie here — please keep it constructive)

Answer 1

Considering you are new, this is a simple recursive solution (in no means the most efficient though):

public static final FileFilter DIRS = new FileFilter() {

  public boolean accept(File file) {
    return file.isDirectory();
  }

};

public static final FileFilter FILES = new FileFilter() {

  public boolean accept(File file) {
    return file.isFile();
  }

}

public void walkTree(File start) throws IOException {

  File[] dirs = start.listFiles(DIRS);
  File[] files = start.listFiles(FILES);

  for (File file : files) {
    if (file.canRead()) {
      if (readAndCheck(file, "string")) {
        // Do Whatever
      }
    }
  }

  for (File dir : dirs) {
    walkTree(dir);
  }

}

public boolean readAndCheck(File file, String string) throws IOException {

  BufferedReader br = null;
  StringBuilder total = new StringBuilder();

  try {

    // If line separators matter in your pattern, consider reading every character
    br = new BufferedReader(new FileReader(file));
    String line;
    while ((line = br.readLine()) != null) {
      total.append(line);
    }

  } finally {
    if (br != null) {
      br.close();
    }
  }

  return total.toString().contains(string);

}

Note: There may be a couple syntax errors as I wrote this in the answerbox.

---

Also, you’re going to have to launch this on a new Thread, preferably using a SwingWorker: