HDFS-16576. Remove unused imports in HDFS project (#4389)

Co-authored-by: Ashutosh Gupta <ashugpt@amazon.com>
Reviewed-by: Tao Li <tomscut@apache.org>
Signed-off-by: Akira Ajisaka <aajisaka@apache.org>

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/WebHdfsFileSystem.java

@@ -138,8 +138,6 @@ import org.apache.hadoop.classification.VisibleForTesting;
 import org.apache.hadoop.thirdparty.com.google.common.base.Charsets;
 import org.apache.hadoop.util.Preconditions;
 
-import static org.apache.hadoop.fs.impl.PathCapabilitiesSupport.validatePathCapabilityArgs;
-
 /** A FileSystem for HDFS over the web. */
 public class WebHdfsFileSystem extends FileSystem
     implements DelegationTokenRenewer.Renewable,

hadoop-hdfs-project/hadoop-hdfs-client/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestConfiguredFailoverProxyProvider.java

@@ -35,7 +35,6 @@ import org.mockito.stubbing.Answer;
 import org.slf4j.event.Level;
 
 import java.io.IOException;
-import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.net.URISyntaxException;

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/client/HttpFSFileSystem.java

@@ -93,7 +93,6 @@ import java.net.URL;
 import java.security.PrivilegedExceptionAction;
 import java.text.MessageFormat;
 import java.util.HashMap;
-import java.util.Locale;
 import java.util.Map;
 
 import static org.apache.hadoop.fs.impl.PathCapabilitiesSupport.validatePathCapabilityArgs;

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/fs/http/client/TestHttpFSFileSystemLocalFileSystem.java

@@ -32,8 +32,6 @@ import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
 import java.io.File;
-import java.net.URI;
-import java.net.URISyntaxException;
 
 @RunWith(value = Parameterized.class)
 public class TestHttpFSFileSystemLocalFileSystem extends BaseTestHttpFSWith {

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/fs/http/server/TestHttpFSAccessControlled.java

@@ -21,7 +21,6 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.security.authentication.server.AuthenticationFilter;
 import org.apache.hadoop.test.HTestCase;

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/server/TestServer.java

@@ -42,7 +42,6 @@ import org.apache.hadoop.test.HTestCase;
 import org.apache.hadoop.test.TestDir;
 import org.apache.hadoop.test.TestDirHelper;
 import org.apache.hadoop.test.TestException;
-import org.apache.hadoop.util.Shell;
 import org.apache.hadoop.util.StringUtils;
 import org.junit.Test;
 

hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/Nfs3HttpServer.java

@@ -25,7 +25,6 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.DFSUtil;
 import org.apache.hadoop.hdfs.nfs.conf.NfsConfigKeys;
 import org.apache.hadoop.hdfs.nfs.conf.NfsConfiguration;
-import org.apache.hadoop.hdfs.server.common.JspHelper;
 import org.apache.hadoop.http.HttpConfig;
 import org.apache.hadoop.http.HttpServer2;
 import org.apache.hadoop.net.NetUtils;

hadoop-hdfs-project/hadoop-hdfs-nfs/src/test/java/org/apache/hadoop/hdfs/nfs/nfs3/TestNfs3Utils.java

@@ -18,8 +18,6 @@
 package org.apache.hadoop.hdfs.nfs.nfs3;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
 
 import org.junit.Test;
 

hadoop-hdfs-project/hadoop-hdfs-rbf/src/test/java/org/apache/hadoop/hdfs/server/federation/router/TestRouterRpcStoragePolicySatisfier.java

@@ -31,7 +31,6 @@ import org.apache.hadoop.hdfs.server.balancer.NameNodeConnector;
 import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
 import org.apache.hadoop.hdfs.server.federation.MiniRouterDFSCluster;
 import org.apache.hadoop.hdfs.server.federation.RouterConfigBuilder;
-import org.apache.hadoop.hdfs.server.federation.metrics.NamenodeBeanMetrics;
 import org.apache.hadoop.hdfs.server.namenode.sps.Context;
 import org.apache.hadoop.hdfs.server.namenode.sps.StoragePolicySatisfier;
 import org.apache.hadoop.hdfs.server.sps.ExternalSPSContext;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/SnapshotInfo.java

@@ -20,7 +20,6 @@ package org.apache.hadoop.hdfs.protocol;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.hdfs.protocol.proto.AclProtos.FsPermissionProto;
-import org.apache.hadoop.hdfs.server.namenode.snapshot.Snapshot;
 
 /**
  * SnapshotInfo maintains information for a snapshot

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Receiver.java

@@ -32,7 +32,6 @@ import org.apache.hadoop.hdfs.protocol.StripedBlockInfo;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.BaseHeaderProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.CachingStrategyProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ClientOperationHeaderProto;
-import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.DataTransferTraceInfoProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpBlockChecksumProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpBlockGroupChecksumProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpCopyBlockProto;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/IncorrectVersionException.java

@@ -21,7 +21,6 @@ import java.io.IOException;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
-import org.apache.hadoop.hdfs.protocol.HdfsConstants;
 
 /**
  * The exception is thrown when external version does not match 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/blockaliasmap/impl/TextFileRegionAliasMap.java

@@ -26,7 +26,6 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
-import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.Base64;
 import java.util.Iterator;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/checker/AbstractFuture.java

@@ -29,7 +29,6 @@ import org.apache.hadoop.thirdparty.com.google.common.util.concurrent.SettableFu
 import org.apache.hadoop.thirdparty.com.google.common.util.concurrent.Uninterruptibles;
 import org.apache.hadoop.util.Preconditions;
 
-import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import static java.util.concurrent.atomic.AtomicReferenceFieldUpdater
     .newUpdater;
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/AclEntryStatusFormat.java

@@ -26,8 +26,6 @@ import org.apache.hadoop.fs.permission.AclEntryType;
 import org.apache.hadoop.fs.permission.FsAction;
 import org.apache.hadoop.hdfs.util.LongBitFormat;
 
-import org.apache.hadoop.thirdparty.com.google.common.collect.ImmutableList;
-
 /**
  * Class to pack an AclEntry into an integer. <br>
  * An ACL entry is represented by a 32-bit integer in Big Endian format. <br>

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/SerialNumberMap.java

@@ -18,7 +18,6 @@
 package org.apache.hadoop.hdfs.server.namenode;
 
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/ha/RemoteNameNodeInfo.java

@@ -24,7 +24,6 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
-import org.apache.hadoop.thirdparty.com.google.common.base.Objects;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.DFSUtil;
 import org.apache.hadoop.hdfs.HAUtil;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/startupprogress/package-info.java

@@ -40,4 +40,3 @@
 package org.apache.hadoop.hdfs.server.namenode.startupprogress;
 
 import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.hdfs.server.namenode.NameNode;

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

@@ -20,7 +20,6 @@ package org.apache.hadoop.hdfs.tools.snapshot;
 import java.io.IOException;
 
 import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.conf.Configured;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.hdfs.DistributedFileSystem;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/TestGenericRefresh.java

@@ -19,9 +19,7 @@
 package org.apache.hadoop;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/fs/TestResolveHdfsSymlink.java

@@ -37,7 +37,6 @@ import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifie
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.security.token.delegation.AbstractDelegationTokenIdentifier;
-import org.apache.hadoop.test.PathUtils;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.junit.AfterClass;
 import org.junit.Assert;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/fs/TestSWebHdfsFileContextMainOperations.java

@@ -17,7 +17,6 @@
  */
 package org.apache.hadoop.fs;
 
-import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.MiniDFSCluster;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/fs/TestSymlinkHdfsFileSystem.java

@@ -17,7 +17,6 @@
  */
 package org.apache.hadoop.fs;
 
-import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFileAppend3.java

@@ -26,7 +26,6 @@ import java.util.EnumSet;
 import java.util.List;
 
 import org.apache.hadoop.fs.CreateFlag;
-import org.apache.hadoop.hdfs.server.datanode.FsDatasetTestUtils.MaterializedReplica;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.mockito.invocation.InvocationOnMock;
 import static org.mockito.Mockito.spy;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestHDFSPolicyProvider.java

@@ -19,9 +19,7 @@ package org.apache.hadoop.hdfs;
 
 import static org.junit.Assert.*;
 
-import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.Comparator;
 import java.util.HashSet;
 import java.util.List;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestModTime.java

@@ -26,8 +26,6 @@ import java.net.InetSocketAddress;
 import java.util.Random;
 
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.fs.CommonConfigurationKeys;
-import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestRollingUpgradeDowngrade.java

@@ -28,7 +28,6 @@ import org.apache.hadoop.hdfs.protocol.HdfsConstants.RollingUpgradeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
 import org.apache.hadoop.hdfs.protocol.RollingUpgradeInfo;
 import org.apache.hadoop.hdfs.qjournal.MiniQJMHACluster;
-import org.apache.hadoop.hdfs.server.common.IncorrectVersionException;
 import org.apache.hadoop.hdfs.server.namenode.NNStorage;
 import org.apache.hadoop.hdfs.server.namenode.NameNodeLayoutVersion;
 import org.junit.Assert;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestSeekBug.java

@@ -20,7 +20,6 @@ package org.apache.hadoop.hdfs;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
-import java.io.DataOutputStream;
 import java.io.IOException;
 import java.util.Random;
 

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestSetTimes.java

@@ -42,7 +42,6 @@ import org.apache.hadoop.test.MockitoUtil;
 import org.apache.hadoop.util.Time;
 import org.junit.Assert;
 import org.junit.Test;
-import org.mockito.Mockito;
 
 /**
  * This class tests the access time on files.

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestSnapshotCommands.java

@@ -25,7 +25,7 @@ import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hdfs.protocol.SnapshotDiffReport;
 import org.apache.hadoop.hdfs.tools.snapshot.SnapshotDiff;
-import org.apache.hadoop.util.ChunkedArrayList;
+
 import org.junit.After;
 import org.junit.AfterClass;
 import org.junit.Before;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeInitStorage.java

@@ -29,10 +29,6 @@ import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsDatasetSpi;
 import org.junit.Test;
 
-import static org.hamcrest.core.IsNot.not;
-import static org.junit.Assert.*;
-
-
 /**
  * Test to verify that the DataNode Uuid is correctly initialized before
  * FsDataSet initialization.

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestDatanodeRestart.java

@@ -18,12 +18,8 @@
 package org.apache.hadoop.hdfs.server.datanode.fsdataset.impl;
 
 import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.RandomAccessFile;
-import java.util.Collection;
-import java.util.Iterator;
 import java.util.Random;
 
 import org.apache.hadoop.conf.Configuration;
@@ -40,7 +36,6 @@ import org.apache.hadoop.hdfs.server.common.HdfsServerConstants.ReplicaState;
 import org.apache.hadoop.hdfs.server.datanode.DataNode;
 import org.apache.hadoop.hdfs.server.datanode.DataNodeFaultInjector;
 import org.apache.hadoop.hdfs.server.datanode.DataNodeTestUtils;
-import org.apache.hadoop.hdfs.server.datanode.DatanodeUtil;
 import org.apache.hadoop.hdfs.server.datanode.ReplicaInfo;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsDatasetSpi;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsVolumeSpi;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestBlockUnderConstruction.java

@@ -45,9 +45,6 @@ import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
-import org.apache.hadoop.hdfs.protocol.proto.HdfsProtos.LocatedBlockProto;
-import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
-
 public class TestBlockUnderConstruction {
   static final String BASE_DIR = "/test/TestBlockUnderConstruction";
   static final int BLOCK_SIZE = 8192; // same as TestFileCreation.blocksize

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestCommitBlockWithInvalidGenStamp.java

@@ -20,14 +20,12 @@ package org.apache.hadoop.hdfs.server.namenode;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.fs.StorageType;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.DistributedFileSystem;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
-import org.apache.hadoop.hdfs.protocol.HdfsConstants;
 import org.apache.hadoop.io.IOUtils;
 import org.junit.After;
 import org.junit.Assert;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFileContextXAttr.java

@@ -29,9 +29,7 @@ import org.apache.hadoop.fs.FileContext;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.XAttrSetFlag;
-import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DistributedFileSystem;
-import org.junit.BeforeClass;
 
 /**
  * Tests of XAttr operations using FileContext APIs.

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFileLimit.java

@@ -30,7 +30,6 @@ import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.client.HdfsDataOutputStream;
 import org.apache.hadoop.hdfs.server.datanode.SimulatedFSDataset;
-import org.apache.hadoop.ipc.RemoteException;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.junit.Test;
 

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFsckWithMultipleNameNodes.java

@@ -28,7 +28,6 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.viewfs.ConfigUtil;
-import org.apache.hadoop.fs.viewfs.ViewFileSystem;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.HdfsConfiguration;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestSecondaryWebUi.java

@@ -21,7 +21,6 @@ import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NAMENODE_CHECKPOINT_TXNS_
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
-import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.junit.AfterClass;
 import org.junit.Assert;
@@ -31,7 +30,6 @@ import org.junit.Test;
 import javax.management.*;
 import java.io.IOException;
 import java.lang.management.ManagementFactory;
-import java.net.URL;
 
 public class TestSecondaryWebUi {
   

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestSecureNameNode.java

@@ -19,7 +19,6 @@ package org.apache.hadoop.hdfs.server.namenode;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.fail;
 
 import java.io.IOException;
 import java.lang.management.ManagementFactory;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestSecureNameNodeWithExternalKdc.java

@@ -19,7 +19,6 @@ package org.apache.hadoop.hdfs.server.namenode;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
 import java.io.IOException;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/snapshot/TestXAttrWithSnapshot.java

@@ -34,7 +34,6 @@ import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DistributedFileSystem;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
-import org.apache.hadoop.hdfs.protocol.NSQuotaExceededException;
 import org.apache.hadoop.hdfs.protocol.SnapshotAccessControlException;
 import org.apache.hadoop.hdfs.protocol.SnapshotDiffReport;
 import org.apache.hadoop.hdfs.server.namenode.NameNode;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/startupprogress/TestStartupProgressMetrics.java

@@ -17,9 +17,7 @@
  */
 package org.apache.hadoop.hdfs.server.namenode.startupprogress;
 
-import static org.apache.hadoop.hdfs.server.namenode.startupprogress.Phase.*;
 import static org.apache.hadoop.hdfs.server.namenode.startupprogress.StartupProgressTestHelper.*;
-import static org.apache.hadoop.hdfs.server.namenode.startupprogress.StepType.*;
 import static org.apache.hadoop.test.MetricsAsserts.*;
 import static org.junit.Assert.*;
 

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitCache.java

@@ -21,7 +21,6 @@ import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_SIZE_KEY;
 import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_CONTEXT;
 import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_DOMAIN_SOCKET_DATA_TRAFFIC;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY;
-import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_TIMEOUT_KEY;
 import static org.hamcrest.CoreMatchers.equalTo;
 
 import java.io.DataOutputStream;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/tools/offlineImageViewer/TestOfflineImageViewerForAcl.java

@@ -21,7 +21,6 @@ import java.io.BufferedReader;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
-import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.PrintStream;
@@ -29,11 +28,9 @@ import java.io.RandomAccessFile;
 import java.io.StringReader;
 import java.net.HttpURLConnection;
 import java.net.URI;
-import java.net.URISyntaxException;
 import java.net.URL;
 import java.util.HashMap;
 
-import javax.xml.parsers.ParserConfigurationException;
 import javax.xml.parsers.SAXParser;
 import javax.xml.parsers.SAXParserFactory;
 
@@ -54,7 +51,6 @@ import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
 import org.xml.sax.InputSource;
-import org.xml.sax.SAXException;
 import org.xml.sax.helpers.DefaultHandler;
 
 import org.apache.hadoop.thirdparty.com.google.common.collect.Maps;

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/tools/TestJMXGet.java

@@ -29,7 +29,6 @@ import java.io.PipedInputStream;
 import java.io.PipedOutputStream;
 import java.io.PrintStream;
 import java.lang.management.ManagementFactory;
-import java.util.Random;
 import java.util.Set;
 import java.util.concurrent.TimeoutException;
 
@@ -37,9 +36,6 @@ import javax.management.MBeanServerConnection;
 import javax.management.ObjectName;
 
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.fs.CommonConfigurationKeys;
-import org.apache.hadoop.fs.FSDataOutputStream;
-import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.FileUtil;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hdfs.DFSTestUtil;