@@ -0,0 +1,1900 @@
+/*%0A * Licensed to the Apache Software Foundation (ASF) under one or more%0A * contributor license agreements.  See the NOTICE file distributed with%0A * this work for additional information regarding copyright ownership.%0A * The ASF licenses this file to You under the Apache License, Version 2.0%0A * (the %22License%22); you may not use this file except in compliance with%0A * the License.  You may obtain a copy of the License at%0A *%0A *      http://www.apache.org/licenses/LICENSE-2.0%0A *%0A * Unless required by applicable law or agreed to in writing, software%0A * distributed under the License is distributed on an %22AS IS%22 BASIS,%0A * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.%0A * See the License for the specific language governing permissions and%0A * limitations under the License.%0A */%0Apackage org.apache.jackrabbit.oak.stats;%0A%0Aimport static junit.framework.Assert.assertTrue;%0A%0Aimport java.util.concurrent.Executors;%0Aimport java.util.concurrent.ScheduledExecutorService;%0A%0Aimport org.junit.Test;%0A%0Apublic class ClockTest %7B%0A%0A    @Test%0A    public void testClockDrift() throws InterruptedException %7B%0A        ScheduledExecutorService executor =%0A                Executors.newSingleThreadScheduledExecutor();%0A        try %7B%0A            Clock%5B%5D clocks = new Clock%5B%5D %7B%0A                    Clock.SIMPLE,%0A                    Clock.ACCURATE,%0A                    new Clock.Fast(executor)%0A            %7D;%0A%0A            for (Clock clock : clocks) %7B%0A                long drift = clock.getTime() - System.currentTimeMillis();%0A                assertTrue(Math.abs(drift) %3C 20); // Windows can have 15ms gaps%0A            %7D%0A%0A            Thread.sleep(100);%0A%0A            for (Clock clock : clocks) %7B%0A                long drift = clock.getTime() - System.currentTimeMillis();%0A                assertTrue(Math.abs(drift) %3C 20);%0A            %7D%0A        %7D finally %7B%0A            executor.shutdown();%0A        %7D%0A    %7D%0A%0A%7D

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