concurrent test

whatsmars-common/src/test/java/org/hongxi/java/util/concurrent/CopyOnWriteArrayListTest.java

+package org.hongxi.java.util.concurrent;
+
+import java.util.Iterator;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+/**
+ * @author shenhongxi 2019/09/01
+ * 验证迭代器的弱一致性
+ */
+public class CopyOnWriteArrayListTest {
+
+    private static volatile CopyOnWriteArrayList<String> arrayList = new CopyOnWriteArrayList<>();
+
+    public static void main(String[] args) {
+        arrayList.add("hello");
+        arrayList.add("alibaba");
+        arrayList.add("welcome");
+        arrayList.add("to");
+        arrayList.add("hangzhou");
+
+        Thread threadOne = new Thread(() -> {
+            arrayList.set(1, "baba");
+            arrayList.remove(2);
+            arrayList.remove(3);
+        });
+
+        // 保证在threadOne启动前获取迭代器
+        Iterator<String> itr = arrayList.iterator();
+
+        threadOne.start();
+
+        while (itr.hasNext()) {
+            System.out.println(itr.next());
+        }
+    }
+}