CallableExample.java

package com.grosdim.randomCallable;

public class CallableExample {

	
	static final int NB_THREADS = 5; 

	public static class StringCallable implements Callable<String>{

		private String stringToUpper;
		
		public StringCallable(String string){
			this.stringToUpper = string;
		}
		
		@Override
		public String call() throws Exception {
			return this.stringToUpper.toUpperCase();
		}		
	}
	
	public static void main(String[] args) throws InterruptedException, ExecutionException{
		
		List<Future<String>> futures = new ArrayList<Future<String>>();
		ExecutorService executor = Executors.newFixedThreadPool(NB_THREADS);
		
		String[] stringArray = {"java", "callable", "myblog", "hello world", "bonjour tout le monde", "What's going on", "etc"};
		
		for( String s : stringArray){
			
			Callable<String> callable = new StringCallable(s);
			Future<String> future = executor.submit(callable);
			futures.add(future);
		}
		
		for(Future<String> f : futures){
			String result = f.get();
			System.out.println(result);
		}
	}
}