HBASE-24898 Use EnvironmentEdge.currentTime() instead of System.currentTimeMillis() in CurrentHourProvider

Closes #2319

Signed-off-by: Viraj Jasani <vjasani@apache.org>
Signed-off-by: Duo Zhang <zhangduo@apache.org>

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/compactions/CurrentHourProvider.java

@@ -17,10 +17,11 @@
  */
 package org.apache.hadoop.hbase.regionserver.compactions;
 
+import com.google.common.annotations.VisibleForTesting;
 import java.util.Calendar;
 import java.util.GregorianCalendar;
-
 import org.apache.hadoop.hbase.classification.InterfaceAudience;
+import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 
 @InterfaceAudience.Private
 public class CurrentHourProvider {
@@ -36,8 +37,10 @@ public class CurrentHourProvider {
     }
   }
 
-  private static Tick nextTick() {
+  @VisibleForTesting
+  static Tick nextTick() {
     Calendar calendar = new GregorianCalendar();
+    calendar.setTimeInMillis(EnvironmentEdgeManager.currentTime());
     int currentHour = calendar.get(Calendar.HOUR_OF_DAY);
     moveToNextHour(calendar);
     return new Tick(currentHour, calendar.getTimeInMillis());
@@ -50,11 +53,12 @@ public class CurrentHourProvider {
     calendar.set(Calendar.MILLISECOND, 0);
   }
 
-  private static volatile Tick tick = nextTick();
+  @VisibleForTesting
+  static volatile Tick tick = nextTick();
 
   public static int getCurrentHour() {
     Tick tick = CurrentHourProvider.tick;
-    if(System.currentTimeMillis() < tick.expirationTimeInMillis) {
+    if (EnvironmentEdgeManager.currentTime() < tick.expirationTimeInMillis) {
       return tick.currentHour;
     }
 

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/compactions/TestCurrentHourProvider.java

@@ -0,0 +1,88 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.hadoop.hbase.regionserver.compactions;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.Date;
+import java.util.TimeZone;
+import org.apache.hadoop.hbase.testclassification.RegionServerTests;
+import org.apache.hadoop.hbase.testclassification.SmallTests;
+import org.apache.hadoop.hbase.util.EnvironmentEdge;
+import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+
+@Category({RegionServerTests.class, SmallTests.class})
+public class TestCurrentHourProvider {
+
+  /**
+   * In timezone GMT+08:00, the unix time of 2020-08-20 11:52:41 is 1597895561000
+   * and the unix time of 2020-08-20 15:04:00 is 1597907081000,
+   * by calculating the delta time to get expected time in current timezone,
+   * then we can get special hour no matter which timezone it runs.
+   *
+   * In addition, we should consider the Daylight Saving Time.
+   * 1. If in DaylightTime, we need reduce one hour.
+   * 2. If in DaylightTime and timezone is "Antarctica/Troll", we need reduce two hours.
+   */
+  @Test
+  public void testWithEnvironmentEdge() {
+    // test for all available zoneID
+    for (String zoneID : TimeZone.getAvailableIDs()) {
+      TimeZone timezone = TimeZone.getTimeZone(zoneID);
+      TimeZone.setDefault(timezone);
+
+      // set a time represent hour 11
+      long deltaFor11 = TimeZone.getDefault().getRawOffset() - 28800000;
+      final long timeFor11 = 1597895561000L - deltaFor11;
+      EnvironmentEdgeManager.injectEdge(new EnvironmentEdge() {
+        @Override
+        public long currentTime() {
+          return timeFor11;
+        }
+      });
+      CurrentHourProvider.tick = CurrentHourProvider.nextTick();
+      int hour11 = CurrentHourProvider.getCurrentHour();
+      if (TimeZone.getDefault().inDaylightTime(new Date(timeFor11))) {
+        hour11 = "Antarctica/Troll".equals(zoneID) ?
+          CurrentHourProvider.getCurrentHour() - 2 :
+          CurrentHourProvider.getCurrentHour() - 1;
+      }
+      assertEquals(11, hour11);
+
+      // set a time represent hour 15
+      long deltaFor15 = TimeZone.getDefault().getRawOffset() - 28800000;
+      final long timeFor15 = 1597907081000L - deltaFor15;
+      EnvironmentEdgeManager.injectEdge(new EnvironmentEdge() {
+        @Override
+        public long currentTime() {
+          return timeFor15;
+        }
+      });
+      CurrentHourProvider.tick = CurrentHourProvider.nextTick();
+      int hour15 = CurrentHourProvider.getCurrentHour();
+      if (TimeZone.getDefault().inDaylightTime(new Date(timeFor15))) {
+        hour15 = "Antarctica/Troll".equals(zoneID) ?
+          CurrentHourProvider.getCurrentHour() - 2 :
+          CurrentHourProvider.getCurrentHour() - 1;
+      }
+      assertEquals(15, hour15);
+    }
+  }
+}