package concurrent;

import java.util.*;
import java.util.concurrent.atomic.*;

public class AtomicIntegerTest {
	
	public static class FakeAtomicInteger {
		private int value;
		int get() {
			return value;
		}
		int incrementAndGet() {
			return ++value;
		}
	}
	
	private AtomicInteger ai = new AtomicInteger();
	//private FakeAtomicInteger ai = new FakeAtomicInteger();
	
	int get() {
		return ai.get();
	}
	
	void run() {
		for (int idx = 0; idx < 1000000; ++idx) {
			ai.incrementAndGet();
		}
	}
	
	public static void runCase(int threadCnt) throws Exception {
		final AtomicIntegerTest aitest = new AtomicIntegerTest();
		ArrayList<Thread> threads = new ArrayList<Thread>();		
		int idx;
		for (idx = 0; idx < threadCnt; ++idx) {
			Runnable runnable = new Runnable(){public void run(){aitest.run();}};
			Thread thread = new Thread(runnable, String.format("%04d", idx));
			threads.add(thread);
		}
		for (idx = 0; idx < threadCnt; ++idx) {
			threads.get(idx).start();
		}
		for (idx = 0; idx < threadCnt; ++idx) {
			threads.get(idx).join();
		}
		System.out.println(aitest.get());
	}
	
	public static void main(String[] args) throws Exception {
		int cnt = 10;
		while (cnt-- > 0)
			runCase(4);
	}
}