Add LongAdder example

winterbe · winterbe · commit e03420cd4136 · 2015-04-11T21:38:29.000+02:00
diff --git a/src/com/winterbe/java8/samples/concurrent/LongAdder1.java b/src/com/winterbe/java8/samples/concurrent/LongAdder1.java
@@ -0,0 +1,43 @@
+package com.winterbe.java8.samples.concurrent;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.atomic.LongAdder;
+import java.util.stream.IntStream;
+
+/**
+ * @author Benjamin Winterberg
+ */
+public class LongAdder1 {
+
+    private static final int NUM_INCREMENTS = 10000;
+
+    private static LongAdder adder = new LongAdder();
+
+    public static void main(String[] args) {
+        testIncrement();
+        testAdd();
+    }
+
+    private static void testAdd() {
+        ExecutorService executor = Executors.newFixedThreadPool(2);
+
+        IntStream.range(0, NUM_INCREMENTS)
+                .forEach(i -> executor.submit(() -> adder.add(2)));
+
+        ConcurrentUtils.stop(executor);
+
+        System.out.format("Add: %d\n", adder.sumThenReset());
+    }
+
+    private static void testIncrement() {
+        ExecutorService executor = Executors.newFixedThreadPool(2);
+
+        IntStream.range(0, NUM_INCREMENTS)
+                .forEach(i -> executor.submit(adder::increment));
+
+        ConcurrentUtils.stop(executor);
+
+        System.out.format("Increment: Expected=%d; Is=%d\n", NUM_INCREMENTS, adder.sumThenReset());
+    }
+}
