YARN-2229. Changed the integer field of ContainerId to be long type. Contributed by Tsuyoshi OZAWA

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/rm/preemption/CheckpointAMPreemptionPolicy.java

@@ -194,7 +194,7 @@ public class CheckpointAMPreemptionPolicy implements AMPreemptionPolicy {
           Collections.sort(listOfCont, new Comparator<Container>() {
             @Override
             public int compare(final Container o1, final Container o2) {
-              return o2.getId().getId() - o1.getId().getId();
+              return o2.getId().compareTo(o1.getId());
             }
           });
 

hadoop-yarn-project/CHANGES.txt

@@ -211,6 +211,9 @@ Release 2.6.0 - UNRELEASED
     YARN-2538. Added logs when RM sends roll-overed AMRMToken to AM. (Xuan Gong
     via zjshen)
 
+    YARN-2229. Changed the integer field of ContainerId to be long type.
+    (Tsuyoshi OZAWA via jianhe)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/api/records/ContainerId.java

@@ -41,9 +41,9 @@ public abstract class ContainerId implements Comparable<ContainerId>{
   @Private
   @Unstable
   public static ContainerId newInstance(ApplicationAttemptId appAttemptId,
-      int containerId) {
+      long containerId) {
     ContainerId id = Records.newRecord(ContainerId.class);
-    id.setId(containerId);
+    id.setContainerId(containerId);
     id.setApplicationAttemptId(appAttemptId);
     id.build();
     return id;
@@ -74,16 +74,28 @@ public abstract class ContainerId implements Comparable<ContainerId>{
   protected abstract void setApplicationAttemptId(ApplicationAttemptId atId);
 
   /**
-   * Get the identifier of the <code>ContainerId</code>.
-   * @return identifier of the <code>ContainerId</code>
+   * Get the lower 32 bits of identifier of the <code>ContainerId</code>,
+   * which doesn't include epoch. Note that this method will be marked as
+   * deprecated, so please use <code>getContainerId</code> instead.
+   * @return lower 32 bits of identifier of the <code>ContainerId</code>
    */
   @Public
   @Stable
   public abstract int getId();
 
+  /**
+   * Get the identifier of the <code>ContainerId</code>. Upper 24 bits are
+   * reserved as epoch of cluster, and lower 40 bits are reserved as
+   * sequential number of containers.
+   * @return identifier of the <code>ContainerId</code>
+   */
+  @Public
+  @Unstable
+  public abstract long getContainerId();
+
   @Private
   @Unstable
-  protected abstract void setId(int id);
+  protected abstract void setContainerId(long id);
  
   
   // TODO: fail the app submission if attempts are more than 10 or something
@@ -109,14 +121,12 @@ public abstract class ContainerId implements Comparable<ContainerId>{
           return fmt;
         }
       };
-  
+
   @Override
   public int hashCode() {
-    // Generated by eclipse.
-    final int prime = 435569;
-    int result = 7507;
-    result = prime * result + getId();
-    result = prime * result + getApplicationAttemptId().hashCode();
+    // Generated by IntelliJ IDEA 13.1.
+    int result = (int) (getContainerId() ^ (getContainerId() >>> 32));
+    result = 31 * result + getApplicationAttemptId().hashCode();
     return result;
   }
 
@@ -131,7 +141,7 @@ public abstract class ContainerId implements Comparable<ContainerId>{
     ContainerId other = (ContainerId) obj;
     if (!this.getApplicationAttemptId().equals(other.getApplicationAttemptId()))
       return false;
-    if (this.getId() != other.getId())
+    if (this.getContainerId() != other.getContainerId())
       return false;
     return true;
   }
@@ -140,12 +150,12 @@ public abstract class ContainerId implements Comparable<ContainerId>{
   public int compareTo(ContainerId other) {
     if (this.getApplicationAttemptId().compareTo(
         other.getApplicationAttemptId()) == 0) {
-      return this.getId() - other.getId();
+      return Long.valueOf(getContainerId())
+          .compareTo(Long.valueOf(other.getContainerId()));
     } else {
       return this.getApplicationAttemptId().compareTo(
           other.getApplicationAttemptId());
     }
-    
   }
 
   @Override
@@ -159,8 +169,8 @@ public abstract class ContainerId implements Comparable<ContainerId>{
     sb.append(
         appAttemptIdAndEpochFormat.get().format(
             getApplicationAttemptId().getAttemptId())).append("_");
-    sb.append(containerIdFormat.get().format(0x3fffff & getId()));
-    int epoch = getId() >> 22;
+    sb.append(containerIdFormat.get().format(0xffffffffffL & getContainerId()));
+    long epoch = getContainerId() >> 40;
     if (epoch > 0) {
       sb.append("_").append(appAttemptIdAndEpochFormat.get().format(epoch));
     }
@@ -177,12 +187,12 @@ public abstract class ContainerId implements Comparable<ContainerId>{
     }
     try {
       ApplicationAttemptId appAttemptID = toApplicationAttemptId(it);
-      int id = Integer.parseInt(it.next());
-      int epoch = 0;
+      long id = Long.parseLong(it.next());
+      long epoch = 0;
       if (it.hasNext()) {
         epoch = Integer.parseInt(it.next());
       }
-      int cid = (epoch << 22) | id;
+      long cid = (epoch << 40) | id;
       ContainerId containerId = ContainerId.newInstance(appAttemptID, cid);
       return containerId;
     } catch (NumberFormatException n) {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/proto/yarn_protos.proto

@@ -50,7 +50,7 @@ message ApplicationAttemptIdProto {
 message ContainerIdProto {
   optional ApplicationIdProto app_id = 1;
   optional ApplicationAttemptIdProto app_attempt_id = 2;
-  optional int32 id = 3;
+  optional int64 id = 3;
 }
 
 message ResourceProto {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/api/records/impl/pb/ContainerIdPBImpl.java

@@ -49,12 +49,18 @@ public class ContainerIdPBImpl extends ContainerId {
 
   @Override
   public int getId() {
+    Preconditions.checkNotNull(proto);
+    return (int) proto.getId();
+  }
+
+  @Override
+  public long getContainerId() {
     Preconditions.checkNotNull(proto);
     return proto.getId();
   }
 
   @Override
-  protected void setId(int id) {
+  protected void setContainerId(long id) {
     Preconditions.checkNotNull(builder);
     builder.setId((id));
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/api/TestContainerId.java

@@ -54,18 +54,26 @@ public class TestContainerId {
     long ts = System.currentTimeMillis();
     ContainerId c6 = newContainerId(36473, 4365472, ts, 25645811);
     Assert.assertEquals("container_10_0001_01_000001", c1.toString());
-    Assert.assertEquals(c1,
-        ContainerId.fromString("container_10_0001_01_000001"));
-    Assert.assertEquals(479987, 0x003fffff & c6.getId());
-    Assert.assertEquals(6, c6.getId() >> 22);
-    Assert.assertEquals("container_" + ts + "_36473_4365472_479987_06",
+    Assert.assertEquals(25645811, 0xffffffffffL & c6.getContainerId());
+    Assert.assertEquals(0, c6.getContainerId() >> 40);
+    Assert.assertEquals("container_" + ts + "_36473_4365472_25645811",
         c6.toString());
-    Assert.assertEquals(c6,
-        ContainerId.fromString("container_" + ts + "_36473_4365472_479987_06"));
+
+    ContainerId c7 = newContainerId(36473, 4365472, ts, 4298334883325L);
+    Assert.assertEquals(999799999997L, 0xffffffffffL & c7.getContainerId());
+    Assert.assertEquals(3, c7.getContainerId() >> 40);
+    Assert.assertEquals(
+        "container_" + ts + "_36473_4365472_999799999997_03", c7.toString());
+
+    ContainerId c8 = newContainerId(36473, 4365472, ts, 844424930131965L);
+    Assert.assertEquals(1099511627773L, 0xffffffffffL & c8.getContainerId());
+    Assert.assertEquals(767, c8.getContainerId() >> 40);
+    Assert.assertEquals(
+        "container_" + ts + "_36473_4365472_1099511627773_767", c8.toString());
   }
 
   public static ContainerId newContainerId(int appId, int appAttemptId,
-      long timestamp, int containerId) {
+      long timestamp, long containerId) {
     ApplicationId applicationId = ApplicationId.newInstance(timestamp, appId);
     ApplicationAttemptId applicationAttemptId =
         ApplicationAttemptId.newInstance(applicationId, appAttemptId);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/util/TestConverterUtils.java

@@ -59,9 +59,24 @@ public class TestConverterUtils {
   public void testContainerIdWithEpoch() throws URISyntaxException {
     ContainerId id = TestContainerId.newContainerId(0, 0, 0, 25645811);
     String cid = ConverterUtils.toString(id);
-    assertEquals("container_0_0000_00_479987_06", cid);
+    assertEquals("container_0_0000_00_25645811", cid);
     ContainerId gen = ConverterUtils.toContainerId(cid);
     assertEquals(gen.toString(), id.toString());
+
+    long ts = System.currentTimeMillis();
+    ContainerId id2 =
+        TestContainerId.newContainerId(36473, 4365472, ts, 4298334883325L);
+    String cid2 = ConverterUtils.toString(id2);
+    assertEquals("container_" + ts + "_36473_4365472_999799999997_03", cid2);
+    ContainerId gen2 = ConverterUtils.toContainerId(cid2);
+    assertEquals(gen2.toString(), id2.toString());
+
+    ContainerId id3 =
+        TestContainerId.newContainerId(36473, 4365472, ts, 844424930131965L);
+    String cid3 = ConverterUtils.toString(id3);
+    assertEquals("container_" + ts + "_36473_4365472_1099511627773_767", cid3);
+    ContainerId gen3 = ConverterUtils.toContainerId(cid3);
+    assertEquals(gen3.toString(), id3.toString());
   }
 
   @Test

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/utils/BuilderUtils.java

@@ -138,12 +138,12 @@ public class BuilderUtils {
   }
 
   public static ContainerId newContainerId(ApplicationAttemptId appAttemptId,
-      int containerId) {
+      long containerId) {
     return ContainerId.newInstance(appAttemptId, containerId);
   }
 
   public static ContainerId newContainerId(int appId, int appAttemptId,
-      long timestamp, int id) {
+      long timestamp, long id) {
     ApplicationId applicationId = newApplicationId(timestamp, appId);
     ApplicationAttemptId applicationAttemptId = newApplicationAttemptId(
         applicationId, appAttemptId);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/RMContext.java

@@ -107,5 +107,5 @@ public interface RMContext {
 
   boolean isWorkPreservingRecoveryEnabled();
   
-  int getEpoch();
+  long getEpoch();
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/RMContextImpl.java

@@ -84,7 +84,7 @@ public class RMContextImpl implements RMContext {
   private RMApplicationHistoryWriter rmApplicationHistoryWriter;
   private SystemMetricsPublisher systemMetricsPublisher;
   private ConfigurationProvider configurationProvider;
-  private int epoch;
+  private long epoch;
 
   /**
    * Default constructor. To be used in conjunction with setter methods for
@@ -375,11 +375,11 @@ public class RMContextImpl implements RMContext {
   }
 
   @Override
-  public int getEpoch() {
+  public long getEpoch() {
     return this.epoch;
   }
 
- void setEpoch(int epoch) {
+ void setEpoch(long epoch) {
     this.epoch = epoch;
   }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/monitor/capacity/ProportionalCapacityPreemptionPolicy.java

@@ -602,8 +602,7 @@ public class ProportionalCapacityPreemptionPolicy implements SchedulingEditPolic
         if (priorityComp != 0) {
           return priorityComp;
         }
-        return b.getContainerId().getId() -
-               a.getContainerId().getId();
+        return b.getContainerId().compareTo(a.getContainerId());
       }
     });
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/FileSystemRMStateStore.java

@@ -165,9 +165,9 @@ public class FileSystemRMStateStore extends RMStateStore {
   }
   
   @Override
-  public synchronized int getAndIncrementEpoch() throws Exception {
+  public synchronized long getAndIncrementEpoch() throws Exception {
     Path epochNodePath = getNodePath(rootDirPath, EPOCH_NODE);
-    int currentEpoch = 0;
+    long currentEpoch = 0;
     if (fs.exists(epochNodePath)) {
       // load current epoch
       FileStatus status = fs.getFileStatus(epochNodePath);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/MemoryRMStateStore.java

@@ -44,7 +44,7 @@ import com.google.common.annotations.VisibleForTesting;
 public class MemoryRMStateStore extends RMStateStore {
   
   RMState state = new RMState();
-  private int epoch = 0;
+  private long epoch = 0L;
   
   @VisibleForTesting
   public RMState getState() {
@@ -56,8 +56,8 @@ public class MemoryRMStateStore extends RMStateStore {
   }
 
   @Override
-  public synchronized int getAndIncrementEpoch() throws Exception {
-    int currentEpoch = epoch;
+  public synchronized long getAndIncrementEpoch() throws Exception {
+    long currentEpoch = epoch;
     epoch = epoch + 1;
     return currentEpoch;
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/NullRMStateStore.java

@@ -49,8 +49,8 @@ public class NullRMStateStore extends RMStateStore {
   }
 
   @Override
-  public synchronized int getAndIncrementEpoch() throws Exception {
-    return 0;
+  public synchronized long getAndIncrementEpoch() throws Exception {
+    return 0L;
   }
 
   @Override

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/RMStateStore.java

@@ -545,7 +545,7 @@ public abstract class RMStateStore extends AbstractService {
   /**
    * Get the current epoch of RM and increment the value.
    */
-  public abstract int getAndIncrementEpoch() throws Exception;
+  public abstract long getAndIncrementEpoch() throws Exception;
   
   /**
    * Blocking API

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/ZKRMStateStore.java

@@ -412,9 +412,9 @@ public class ZKRMStateStore extends RMStateStore {
   }
 
   @Override
-  public synchronized int getAndIncrementEpoch() throws Exception {
+  public synchronized long getAndIncrementEpoch() throws Exception {
     String epochNodePath = getNodePath(zkRootNodePath, EPOCH_NODE);
-    int currentEpoch = 0;
+    long currentEpoch = 0;
     if (existsWithRetries(epochNodePath, true) != null) {
       // load current epoch
       byte[] data = getDataWithRetries(epochNodePath, true);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/records/Epoch.java

@@ -32,15 +32,15 @@ import org.apache.hadoop.yarn.util.Records;
 @Unstable
 public abstract class Epoch {
 
-  public static Epoch newInstance(int sequenceNumber) {
+  public static Epoch newInstance(long sequenceNumber) {
     Epoch epoch = Records.newRecord(Epoch.class);
     epoch.setEpoch(sequenceNumber);
     return epoch;
   }
 
-  public abstract int getEpoch();
+  public abstract long getEpoch();
 
-  public abstract void setEpoch(int sequenceNumber);
+  public abstract void setEpoch(long sequenceNumber);
 
   public abstract EpochProto getProto();
 
@@ -50,10 +50,7 @@ public abstract class Epoch {
 
   @Override
   public int hashCode() {
-    final int prime = 31;
-    int result = 1;
-    result = prime * result + getEpoch();
-    return result;
+    return (int) (getEpoch() ^ (getEpoch() >>> 32));
   }
 
   @Override

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/records/impl/pb/EpochPBImpl.java

@@ -53,13 +53,13 @@ public class EpochPBImpl extends Epoch {
   }
 
   @Override
-  public int getEpoch() {
+  public long getEpoch() {
     EpochProtoOrBuilder p = viaProto ? proto : builder;
-    return (int) (p.getEpoch() & 0xffffffff);
+    return p.getEpoch();
   }
 
   @Override
-  public void setEpoch(int sequentialNumber) {
+  public void setEpoch(long sequentialNumber) {
     maybeInitBuilder();
     builder.setEpoch(sequentialNumber);
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/AppSchedulingInfo.java

@@ -26,7 +26,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.TreeSet;
-import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -58,9 +58,8 @@ public class AppSchedulingInfo {
   Queue queue;
   final String user;
   // TODO making containerIdCounter long
-  private final AtomicInteger containerIdCounter;
-  private final int EPOCH_BIT_MASK = 0x3ff;
-  private final int EPOCH_BIT_SHIFT = 22;
+  private final AtomicLong containerIdCounter;
+  private final int EPOCH_BIT_SHIFT = 40;
 
   final Set<Priority> priorities = new TreeSet<Priority>(
       new org.apache.hadoop.yarn.server.resourcemanager.resource.Priority.Comparator());
@@ -77,15 +76,14 @@ public class AppSchedulingInfo {
  
   public AppSchedulingInfo(ApplicationAttemptId appAttemptId,
       String user, Queue queue, ActiveUsersManager activeUsersManager,
-      int epoch) {
+      long epoch) {
     this.applicationAttemptId = appAttemptId;
     this.applicationId = appAttemptId.getApplicationId();
     this.queue = queue;
     this.queueName = queue.getQueueName();
     this.user = user;
     this.activeUsersManager = activeUsersManager;
-    this.containerIdCounter = new AtomicInteger(
-        (epoch & EPOCH_BIT_MASK) << EPOCH_BIT_SHIFT);
+    this.containerIdCounter = new AtomicLong(epoch << EPOCH_BIT_SHIFT);
   }
 
   public ApplicationId getApplicationId() {
@@ -117,7 +115,7 @@ public class AppSchedulingInfo {
     LOG.info("Application " + applicationId + " requests cleared");
   }
 
-  public int getNewContainerId() {
+  public long getNewContainerId() {
     return this.containerIdCounter.incrementAndGet();
   }
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/SchedulerApplicationAttempt.java

@@ -182,7 +182,7 @@ public class SchedulerApplicationAttempt {
     return this.pendingRelease;
   }
 
-  public int getNewContainerId() {
+  public long getNewContainerId() {
     return appSchedulingInfo.getNewContainerId();
   }
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/TestWorkPreservingRMRestart.java

@@ -238,7 +238,7 @@ public class TestWorkPreservingRMRestart {
     }
 
     // *********** check appSchedulingInfo state ***********
-    assertEquals((1 << 22) + 1, schedulerAttempt.getNewContainerId());
+    assertEquals((1L << 40) + 1L, schedulerAttempt.getNewContainerId());
   }
 
   private void checkCSQueue(MockRM rm,

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/RMStateStoreTestBase.java

@@ -508,13 +508,13 @@ public class RMStateStoreTestBase extends ClientBaseWithFixes{
     RMStateStore store = stateStoreHelper.getRMStateStore();
     store.setRMDispatcher(new TestDispatcher());
     
-    int firstTimeEpoch = store.getAndIncrementEpoch();
+    long firstTimeEpoch = store.getAndIncrementEpoch();
     Assert.assertEquals(0, firstTimeEpoch);
     
-    int secondTimeEpoch = store.getAndIncrementEpoch();
+    long secondTimeEpoch = store.getAndIncrementEpoch();
     Assert.assertEquals(1, secondTimeEpoch);
     
-    int thirdTimeEpoch = store.getAndIncrementEpoch();
+    long thirdTimeEpoch = store.getAndIncrementEpoch();
     Assert.assertEquals(2, thirdTimeEpoch);
   }
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/TestSchedulerApplicationAttempt.java

@@ -63,13 +63,13 @@ public class TestSchedulerApplicationAttempt {
 
     ApplicationAttemptId appAttId = createAppAttemptId(0, 0);
     RMContext rmContext = mock(RMContext.class);
-    when(rmContext.getEpoch()).thenReturn(3);
+    when(rmContext.getEpoch()).thenReturn(3L);
     SchedulerApplicationAttempt app = new SchedulerApplicationAttempt(appAttId,
         user, oldQueue, oldQueue.getActiveUsersManager(), rmContext);
     oldMetrics.submitApp(user);
     
     // confirm that containerId is calculated based on epoch.
-    assertEquals(app.getNewContainerId(), 0x00c00001);
+    assertEquals(0x30000000001L, app.getNewContainerId());
     
     // Resource request
     Resource requestedResource = Resource.newInstance(1536, 2);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/TestUtils.java

@@ -172,7 +172,9 @@ public class TestUtils {
     ContainerId containerId = mock(ContainerId.class);
     doReturn(application.getApplicationAttemptId()).
     when(containerId).getApplicationAttemptId();
-    doReturn(application.getNewContainerId()).when(containerId).getId();
+    long id = application.getNewContainerId();
+    doReturn((int)id).when(containerId).getId();
+    doReturn(id).when(containerId).getContainerId();
     return containerId;
   }
   

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/TestMaxRunningAppsEnforcer.java

@@ -63,7 +63,7 @@ public class TestMaxRunningAppsEnforcer {
     maxAppsEnforcer = new MaxRunningAppsEnforcer(scheduler);
     appNum = 0;
     rmContext = mock(RMContext.class);
-    when(rmContext.getEpoch()).thenReturn(0);
+    when(rmContext.getEpoch()).thenReturn(0L);
   }
   
   private FSAppAttempt addApp(FSLeafQueue queue, String user) {