package future;

import java.io.*;

import java.util.Scanner;

import java.util.concurrent.*;

import java.util.*;

public class FutureTest {

public static void main(String[] args) {

// TODO Auto-generated method stub

Scanner in=new Scanner(System.in);

System.out.print("Enter base directory(e.g. /usr/local/jdk5.0/src):");

String directory=in.nextLine();

System.out.print("Enter keyword (e.g. volatile):");

String keyword=in.nextLine();

MatchCounter counter=new MatchCounter(new File(directory),keyword);

FutureTask<Integer> task=new FutureTask<>(counter);

Thread t=new Thread(task);

t.start();

try {

System.out.println(task.get()+ "matching files.");

} catch (InterruptedException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (ExecutionException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

class MatchCounter implements Callable<Integer>{

private File directory;

private String keyword;

private int count;

public MatchCounter(File directory,String keyword){

this.directory=directory;

this.keyword=keyword;

}

@Override

public Integer call() {

// TODO Auto-generated method stub

count=0;

try {

File[] files=directory.listFiles();

List<Future<Integer>> results=new ArrayList<>();

for(File file:files)

if(file.isDirectory()){

MatchCounter counter=new MatchCounter(file,keyword);

FutureTask<Integer> task=new FutureTask<>(counter);

results.add(task);

Thread t=new Thread(task);

t.start();

}

else

{

if(search(file)) count++;

}

for(Future<Integer> result:results)

try{

count+=result.get();

}catch(ExecutionException e){

e.printStackTrace();

}

} catch (InterruptedException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return count;

}

public boolean search(File file){

try{

try(Scanner in=new Scanner(file)){

boolean found=false;

while(!found&&in.hasNext()){

String line=in.nextLine();

if(line.contains(keyword))

found=true;

}

if(!found)

System.out.println(file.getAbsolutePath());

return found;

}

}catch(IOException e){

return false;

}

}

}