FileSysytem Crawler

src_java_Crawler_fileCrawler.java

package Crawler;

import java.awt.*;
import java.io.File;
import java.util.ArrayList;
import java.util.Scanner;

/**
 * Created by Sanitarium on 3/4/2016.
 */
public class fileCrawler {

    public WorkQueue workQ;
    public ArrayList directories = new ArrayList();
    static int i = 0;

    private class Worker implements Runnable {

        private WorkQueue queue;

        public Worker(WorkQueue q) {
            queue = q;
        }

//  since main thread has placed all directories into the workQ, we
//  know that all of them are legal directories; therefore, do not need
//  to try ... catch in the while loop below

        public void run() {
            String name;
            while ((name = queue.remove()) != null) {
                File file = new File(name);
                String entries[] = file.list();
                if (entries == null)
                    continue;
                for (String entry : entries) {
                    if (entry.compareTo(".") == 0)
                        continue;
                    if (entry.compareTo("..") == 0)
                        continue;
                    String fn = name + "\\" + entry;
                    directories.add(fn);
                    System.out.println(fn);
                }
            }
        }
    }

    public fileCrawler() {
        workQ = new WorkQueue();
    }

    public Worker createWorker() {
        return new Worker(workQ);
    }


// need try ... catch below in case the directory is not legal

    public void processDirectory(String dir) {
        try{
            File file = new File(dir);
            if (file.isDirectory()) {
                String entries[] = file.list();
                if (entries != null)
                {
                    workQ.add(dir);

                }

                for (String entry : entries) {
                    String subdir;
                    if (entry.compareTo(".") == 0)
                        continue;
                    if (entry.compareTo("..") == 0)
                        continue;
                    if (dir.endsWith("\\"))
                        subdir = dir+entry;
                    else
                        subdir = dir+"\\"+entry;
                    processDirectory(subdir);
                }
            }}catch(Exception e){}
    }

    public static void main(String Args[]) {

        fileCrawler fc = new fileCrawler();

//  now start all of the worker threads

        int N = 5;
        ArrayList<Thread> thread = new ArrayList<Thread>(N);
        for (int i = 0; i < N; i++) {
            Thread t = new Thread(fc.createWorker());
            thread.add(t);
            t.start();
        }

//  now place each directory into the workQ

        fc.processDirectory("C:\\Users\\Sanitarium\\IdeaProjects\\FileCrawler\\src\\test\\Crawler\\TD");

//  indicate that there are no more directories to add

        fc.workQ.finish();

        for (int i = 0; i < N; i++){
            try {
                thread.get(i).join();
            } catch (Exception e) {};
        }


        System.out.println("Enter keyword to list corresponding paths: ");
        Scanner sc = new Scanner(System.in);
        String key = sc.nextLine();

        System.out.println("******************************************\n");
        for (int i =0; i< fc.directories.size() ; i++)
        {
            String temp = (String) fc.directories.get(i);
            int j = temp.indexOf(key);

            if (j != -1)
            {
                System.out.println(fc.directories.get(i));
            }

        }
    }
}

src_java_Crawler_WorkQueue.java

package Crawler;

/**
 * Created by Sanitarium on 3/4/2016.
 */
import java.util.*;

public class WorkQueue {

    //
// since we are providing the concurrency control, can use non-thread-safe
// linked list
//
    private LinkedList<String> workQ;
    private boolean done;  // no more directories to be added
    private int size;  // number of directories in the queue

    public WorkQueue() {
        workQ = new LinkedList<String>();
        done = false;
        size = 0;
    }

    public synchronized void add(String s) {
        workQ.add(s);
        size++;
        notifyAll();
    }

    public synchronized String remove() {
        String s;
        while (!done && size == 0) {
            try {
                wait();
            } catch (Exception e) {};
        }
        if (size > 0) {
            s = workQ.remove();
            size--;
            notifyAll();
        } else
            s = null;
        return s;
    }

    public synchronized void finish() {
        done = true;
        notifyAll();
    }
}

src_test_Crawler_fileCrawlerTest.java

package Crawler;

import org.junit.Test;

import java.util.ArrayList;

import static org.junit.Assert.*;

/**
 * Created by Sanitarium on 3/4/2016.
 */
public class fileCrawlerTest {

    @Test
    public void testProcessDirectory() throws Exception {

        fileCrawler f = new fileCrawler();
        int N = 1;
        ArrayList<Thread> thread = new ArrayList<Thread>(N);
        for (int i = 0; i < N; i++) {
            Thread t = new Thread(f.createWorker());
            thread.add(t);
            t.start();
        }
        f.processDirectory("C:\\Users\\Sanitarium\\IdeaProjects\\FileCrawler\\src\\test\\Crawler\\TD");
        f.workQ.finish();

        for (int i = 0; i < N; i++){
            try {
                thread.get(i).join();
            } catch (Exception e) {};
        }
        String t = (String) f.directories.get(0);
        assertEquals(t,"C:\\Users\\Sanitarium\\IdeaProjects\\FileCrawler\\src\\test\\Crawler\\TD\\Doc.txt" );
    }
}