Add ParallelGC to reproduce system_server hang

Change-Id: Ie563663df5fc744755102719378446b9efa16cf3
diff --git a/test/ParallelGC/ParallelGC.java b/test/ParallelGC/ParallelGC.java
new file mode 100644
index 0000000..13cb603
--- /dev/null
+++ b/test/ParallelGC/ParallelGC.java
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.ArrayList;
+import java.util.List;
+
+class ParallelGC implements Runnable {
+    public static void main(String[] args) throws Exception {
+        Thread[] threads = new Thread[16];
+        for (int i = 0; i < threads.length; i++) {
+            threads[i] = new Thread(new ParallelGC(i));
+        }
+        for (Thread thread : threads) {
+            thread.start();
+        }
+        for (Thread thread : threads) {
+            thread.join();
+        }
+    }
+
+    private final int id;
+
+    private ParallelGC(int id) {
+        this.id = id;
+    }
+
+    public void run() {
+        List l = new ArrayList();
+        for (int i = 0; i < 1000; i++) {
+            l.add(new ArrayList(i));
+            if (false) {
+                System.out.print(id);
+            }
+        }
+    }
+}