/** * @author xjn * @since 2020-03-01 */ public class ThreadSafeCache { int result; public int getResult() { return result; } public void setResult(int result) { this.result = result; } public static void main(String[] args) { ThreadSafeCache threadSafeCache = new ThreadSafeCache(); for (int i = 0; i < 8; i++) { new Thread(() -> { int x = 0; while (threadSafeCache.getResult() < 100) { x++; } System.out.println(x); }).start(); } try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } threadSafeCache.setResult(200); } }