Added copyright notice, made constants constant, added GC call before each test.

benchmarks/ProtoBench.java

+// Protocol Buffers - Google's data interchange format
+// Copyright 2009 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
 package com.google.protocolbuffers;
 
 import java.io.ByteArrayInputStream;
@@ -13,8 +43,8 @@ import com.google.protobuf.Message;
 
 public class ProtoBench {
   
-  private static long MIN_SAMPLE_TIME_MS = 2 * 1000;
-  private static long TARGET_TIME_MS = 30 * 1000;
+  private static final long MIN_SAMPLE_TIME_MS = 2 * 1000;
+  private static final long TARGET_TIME_MS = 30 * 1000;
 
   private ProtoBench() {
     // Prevent instantiation
@@ -110,6 +140,7 @@ public class ProtoBench {
       iterations *= 2;
       elapsed = timeAction(action, iterations);
     }
+    
     // Upscale the sample to the target time. Do this in floating point arithmetic
     // to avoid overflow issues.
     iterations = (int) ((TARGET_TIME_MS / (double) elapsed) * iterations);
@@ -121,6 +152,7 @@ public class ProtoBench {
   }
   
   private static long timeAction(Action action, int iterations) throws IOException {
+    System.gc();    
     long start = System.currentTimeMillis();
     for (int i = 0; i < iterations; i++) {
       action.execute();