HADOOP-14957. ReconfigurationTaskStatus is exposing guava Optional in its public api. Contributed by Haibo Chen, Xiao Chen.

(cherry picked from commit e3f25f361720b544b464c5e4fbeb4f31e6c53c67)

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/ReconfigurableBase.java

@@ -19,7 +19,6 @@
 package org.apache.hadoop.conf;
 
 import com.google.common.annotations.VisibleForTesting;
-import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.Maps;
 import org.apache.hadoop.util.Time;
@@ -31,6 +30,7 @@ import java.io.IOException;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Map;
+import java.util.Optional;
 
 /**
  * Utility base class for implementing the Reconfigurable interface.
@@ -148,7 +148,7 @@ public abstract class ReconfigurableBase
         } catch (ReconfigurationException e) {
           errorMessage = e.getCause().getMessage();
         }
-        results.put(change, Optional.fromNullable(errorMessage));
+        results.put(change, Optional.ofNullable(errorMessage));
       }
 
       synchronized (parent.reconfigLock) {

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/ReconfigurationTaskStatus.java

@@ -18,15 +18,15 @@
 
 package org.apache.hadoop.conf;
 
-import com.google.common.base.Optional;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.ReconfigurationUtil.PropertyChange;
 
 import java.util.Map;
+import java.util.Optional;
 
-@InterfaceAudience.Public
-@InterfaceStability.Stable
+@InterfaceAudience.LimitedPrivate({"HDFS", "Management Tools"})
+@InterfaceStability.Unstable
 public class ReconfigurationTaskStatus {
   long startTime;
   long endTime;

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/conf/TestReconfiguration.java

@@ -18,7 +18,6 @@
 
 package org.apache.hadoop.conf;
 
-import com.google.common.base.Optional;
 import com.google.common.base.Supplier;
 import com.google.common.collect.Lists;
 import org.apache.hadoop.test.GenericTestUtils;
@@ -44,6 +43,7 @@ import java.util.Collection;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeoutException;
 

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocolPB/ReconfigurationProtocolUtils.java

@@ -19,13 +19,13 @@
 package org.apache.hadoop.hdfs.protocolPB;
 
 import java.util.Map;
+import java.util.Optional;
 
 import org.apache.hadoop.conf.ReconfigurationTaskStatus;
 import org.apache.hadoop.conf.ReconfigurationUtil.PropertyChange;
 import org.apache.hadoop.hdfs.protocol.proto.ReconfigurationProtocolProtos.GetReconfigurationStatusConfigChangeProto;
 import org.apache.hadoop.hdfs.protocol.proto.ReconfigurationProtocolProtos.GetReconfigurationStatusResponseProto;
 
-import com.google.common.base.Optional;
 import com.google.common.collect.Maps;
 
 /**
@@ -56,7 +56,7 @@ public final class ReconfigurationProtocolUtils {
         if (change.hasErrorMessage()) {
           errorMessage = change.getErrorMessage();
         }
-        statusMap.put(pc, Optional.fromNullable(errorMessage));
+        statusMap.put(pc, Optional.ofNullable(errorMessage));
       }
     }
     return new ReconfigurationTaskStatus(startTime, endTime, statusMap);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/ReconfigurationProtocolServerSideUtils.java

@@ -19,6 +19,7 @@ package org.apache.hadoop.hdfs.protocolPB;
 
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 
 import org.apache.hadoop.conf.ReconfigurationTaskStatus;
 import org.apache.hadoop.conf.ReconfigurationUtil.PropertyChange;
@@ -26,8 +27,6 @@ import org.apache.hadoop.hdfs.protocol.proto.ReconfigurationProtocolProtos.GetRe
 import org.apache.hadoop.hdfs.protocol.proto.ReconfigurationProtocolProtos.GetReconfigurationStatusResponseProto;
 import org.apache.hadoop.hdfs.protocol.proto.ReconfigurationProtocolProtos.ListReconfigurablePropertiesResponseProto;
 
-import com.google.common.base.Optional;
-
 /**
  * This is a server side utility class that handles
  * common logic to to parameter reconfiguration.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/DFSAdmin.java

@@ -33,11 +33,11 @@ import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.TreeSet;
 import java.util.concurrent.TimeUnit;
 
 import com.google.common.base.Joiner;
-import com.google.common.base.Optional;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;