add demo for interrupt

src/main/java/threaddemo/InterruptTest.java

@@ -0,0 +1,40 @@
+package threaddemo;
+
+public class InterruptTest implements Runnable{
+    @Override
+    public void run() {
+        try {
+            while(true) {
+                boolean a = Thread.currentThread().isInterrupted();
+                System.out.println(STR."in run() - about to sleep for 20 seconds------- \{a}");
+                Thread.sleep(20000L);
+            }
+        } catch (InterruptedException e) {
+            //如果不加上这一句，那么cd将会都是false，因为在捕捉到InterruptedException异常的时候就会自动的中断标志置为了false
+            Thread.currentThread().interrupt();
+            boolean c = Thread.interrupted(); //true
+            boolean d = Thread.interrupted(); //false
+
+            System.out.println(STR."c =  \{c}");
+            System.out.println(STR."d = \{d}");
+        }
+    }
+
+    public static void main(String[] args) {
+        InterruptTest it = new InterruptTest();
+        Thread t = new Thread(it);
+
+        t.start();
+
+        try {
+            Thread.sleep(2000L);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+
+        System.out.println("in main() - interrupting other thread");
+        //中断线程t
+        t.interrupt();
+        System.out.println("in main() - leaving");
+    }
+}