Hierarchy For Package org.apache.hadoop.hbase.util

Package Hierarchies:

• All Packages

Class Hierarchy

• java.lang.Object
  • org.apache.hadoop.hbase.util.AbstractByteRange (implements org.apache.hadoop.hbase.util.ByteRange)
    • org.apache.hadoop.hbase.util.AbstractPositionedByteRange (implements org.apache.hadoop.hbase.util.PositionedByteRange)
      • org.apache.hadoop.hbase.util.SimplePositionedByteRange
      • org.apache.hadoop.hbase.util.SimplePositionedMutableByteRange
    • org.apache.hadoop.hbase.util.SimpleByteRange
    • org.apache.hadoop.hbase.util.SimpleMutableByteRange
  • java.util.AbstractCollection<E> (implements java.util.Collection<E>)
    • java.util.AbstractQueue<E> (implements java.util.Queue<E>)
      • org.apache.hadoop.hbase.util.BoundedPriorityBlockingQueue<E> (implements java.util.concurrent.BlockingQueue<E>)
      • java.util.concurrent.ConcurrentLinkedQueue<E> (implements java.util.Queue<E>, java.io.Serializable)
        • org.apache.hadoop.hbase.util.PoolMap.ReusablePool<R> (implements org.apache.hadoop.hbase.util.PoolMap.Pool<R>)
      • java.util.concurrent.PriorityBlockingQueue<E> (implements java.util.concurrent.BlockingQueue<E>, java.io.Serializable)
        • org.apache.hadoop.hbase.util.StealJobQueue<T>
    • org.apache.hadoop.hbase.util.ConcatenatedLists<T>
  • org.apache.hadoop.hbase.util.AbstractFileStatusFilter (implements org.apache.hadoop.hbase.util.FileStatusFilter, org.apache.hadoop.fs.PathFilter)
    • org.apache.hadoop.hbase.util.FSUtils.BlackListDirFilter
      • org.apache.hadoop.hbase.util.FSUtils.DirFilter
      • org.apache.hadoop.hbase.util.FSUtils.UserTableDirFilter
    • org.apache.hadoop.hbase.util.FSUtils.FamilyDirFilter
    • org.apache.hadoop.hbase.util.FSUtils.FileFilter
    • org.apache.hadoop.hbase.util.FSUtils.HFileFilter
    • org.apache.hadoop.hbase.util.FSUtils.ReferenceFileFilter
    • org.apache.hadoop.hbase.util.FSUtils.RegionDirFilter
  • org.apache.hadoop.hbase.util.AbstractHBaseTool (implements org.apache.hadoop.util.Tool)
    • org.apache.hadoop.hbase.util.RegionMover (implements java.io.Closeable)
  • org.apache.hadoop.hbase.util.AbstractHBaseTool.OptionsOrderComparator (implements java.util.Comparator<T>)
  • org.apache.hadoop.hbase.util.Addressing
  • org.apache.hadoop.hbase.util.AtomicUtils
  • org.apache.hadoop.hbase.util.AvlUtil
  • org.apache.hadoop.hbase.util.AvlUtil.AvlIterableList
  • org.apache.hadoop.hbase.util.AvlUtil.AvlNode<TNode>
    • org.apache.hadoop.hbase.util.AvlUtil.AvlLinkedNode<TNode>
  • org.apache.hadoop.hbase.util.AvlUtil.AvlTree
  • org.apache.hadoop.hbase.util.AvlUtil.AvlTreeIterator<TNode> (implements java.util.Iterator<E>)
  • org.apache.hadoop.hbase.util.BloomContext
    • org.apache.hadoop.hbase.util.RowBloomContext
      • org.apache.hadoop.hbase.util.RowPrefixFixedLengthBloomContext
    • org.apache.hadoop.hbase.util.RowColBloomContext
  • org.apache.hadoop.hbase.util.BloomFilterChunk (implements org.apache.hadoop.hbase.util.BloomFilterBase)
  • org.apache.hadoop.hbase.util.BloomFilterFactory
  • org.apache.hadoop.hbase.util.BloomFilterUtil
  • org.apache.hadoop.hbase.util.BoundedCompletionService<V>
  • org.apache.hadoop.hbase.util.BoundedPriorityBlockingQueue.PriorityQueue<E>
  • org.apache.hadoop.hbase.util.ByteBufferArray
  • org.apache.hadoop.hbase.util.ByteBufferArray.BufferCreatorCallable (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.ByteBufferExtendedCell (implements org.apache.hadoop.hbase.ExtendedCell)
    • org.apache.hadoop.hbase.util.MapReduceExtendedCell
  • org.apache.hadoop.hbase.util.ByteBufferUtils
  • org.apache.hadoop.hbase.util.ByteBufferUtils.Comparer
    • org.apache.hadoop.hbase.util.ByteBufferUtils.ComparerHolder.PureJavaComparer
    • org.apache.hadoop.hbase.util.ByteBufferUtils.ComparerHolder.UnsafeComparer
  • org.apache.hadoop.hbase.util.ByteBufferUtils.ComparerHolder
  • org.apache.hadoop.hbase.util.ByteBufferUtils.Converter
    • org.apache.hadoop.hbase.util.ByteBufferUtils.ConverterHolder.PureJavaConverter
    • org.apache.hadoop.hbase.util.ByteBufferUtils.ConverterHolder.UnsafeConverter
  • org.apache.hadoop.hbase.util.ByteBufferUtils.ConverterHolder
  • org.apache.hadoop.hbase.util.ByteRangeUtils
  • org.apache.hadoop.hbase.util.Bytes (implements java.lang.Comparable<T>)
  • org.apache.hadoop.hbase.util.Bytes.ByteArrayComparator (implements org.apache.hadoop.io.RawComparator<T>)
    • org.apache.hadoop.hbase.util.Bytes.RowEndKeyComparator
  • org.apache.hadoop.hbase.util.Bytes.Converter
    • org.apache.hadoop.hbase.util.Bytes.ConverterHolder.PureJavaConverter
    • org.apache.hadoop.hbase.util.Bytes.ConverterHolder.UnsafeConverter
  • org.apache.hadoop.hbase.util.Bytes.ConverterHolder
  • org.apache.hadoop.hbase.util.Bytes.LexicographicalComparerHolder
  • org.apache.hadoop.hbase.util.ByteStringer
  • org.apache.hadoop.hbase.util.Classes
  • java.lang.ClassLoader
    • java.security.SecureClassLoader
      • java.net.URLClassLoader (implements java.io.Closeable)
        • org.apache.hadoop.hbase.util.ClassLoaderBase
          • org.apache.hadoop.hbase.util.CoprocessorClassLoader
          • org.apache.hadoop.hbase.util.DynamicClassLoader
  • org.apache.hadoop.hbase.util.ClassSize
  • org.apache.hadoop.hbase.util.ClassSize.MemoryLayout
    • org.apache.hadoop.hbase.util.ClassSize.UnsafeLayout
  • org.apache.hadoop.hbase.util.ClassSize.UnsafeLayout.HeaderSize
  • org.apache.hadoop.hbase.util.ClientUtils
  • org.apache.hadoop.hbase.util.CommonFSUtils
    • org.apache.hadoop.hbase.util.FSUtils
      • org.apache.hadoop.hbase.util.FSHDFSUtils
  • org.apache.hadoop.hbase.util.CommonFSUtils.DfsBuilderUtility
  • org.apache.hadoop.hbase.util.CommonFSUtils.StreamCapabilities
  • org.apache.hadoop.hbase.util.CompressionTest
  • org.apache.hadoop.hbase.util.ConcatenatedLists.Iterator (implements java.util.Iterator<E>)
  • org.apache.hadoop.hbase.util.ConcurrentMapUtils
    • org.apache.hadoop.hbase.util.CollectionUtils
  • org.apache.hadoop.hbase.util.ConfigurationUtil
  • org.apache.hadoop.conf.Configured (implements org.apache.hadoop.conf.Configurable)
    • org.apache.hadoop.hbase.util.HBaseFsck (implements java.io.Closeable)
    • org.apache.hadoop.hbase.util.HBaseFsck.HBaseFsckTool (implements org.apache.hadoop.util.Tool)
    • org.apache.hadoop.hbase.util.ServerCommandLine (implements org.apache.hadoop.util.Tool)
  • org.apache.hadoop.hbase.util.ConnectionCache
  • org.apache.hadoop.hbase.util.ConnectionCache.ConnectionInfo
  • java.util.concurrent.CopyOnWriteArrayList<E> (implements java.lang.Cloneable, java.util.List<E>, java.util.RandomAccess, java.io.Serializable)
    • org.apache.hadoop.hbase.util.PoolMap.RoundRobinPool<R> (implements org.apache.hadoop.hbase.util.PoolMap.Pool<R>)
  • org.apache.hadoop.hbase.util.Counter
  • org.apache.hadoop.hbase.util.Counter.Cell
  • org.apache.hadoop.hbase.util.Counter.Container
  • org.apache.hadoop.hbase.util.DefaultEnvironmentEdge (implements org.apache.hadoop.hbase.util.EnvironmentEdge)
  • org.apache.hadoop.hbase.util.DirectMemoryUtils
  • org.apache.hadoop.hbase.util.DNS
  • org.apache.hadoop.hbase.util.EncryptionTest
  • org.apache.hadoop.hbase.util.EnvironmentEdgeManager
  • org.apache.hadoop.hbase.util.ExceptionUtil
  • org.apache.hadoop.hbase.util.ForeignExceptionUtil
  • org.apache.hadoop.hbase.util.FSRegionScanner (implements java.lang.Runnable)
  • org.apache.hadoop.hbase.util.FSTableDescriptors (implements org.apache.hadoop.hbase.TableDescriptors)
  • org.apache.hadoop.hbase.util.FSUtils.HFileLinkFilter (implements org.apache.hadoop.fs.PathFilter)
  • org.apache.hadoop.hbase.util.FSVisitor
  • java.util.concurrent.FutureTask<V> (implements java.util.concurrent.RunnableFuture<V>)
    • org.apache.hadoop.hbase.util.BoundedCompletionService.QueueingFuture
  • org.apache.hadoop.hbase.util.FutureUtils
  • org.apache.hadoop.hbase.util.GetJavaProperty
  • org.apache.hadoop.hbase.util.GsonUtil
  • org.apache.hadoop.hbase.util.Hash
    • org.apache.hadoop.hbase.util.JenkinsHash
    • org.apache.hadoop.hbase.util.MurmurHash
    • org.apache.hadoop.hbase.util.MurmurHash3
  • org.apache.hadoop.hbase.util.HashedBytes
  • org.apache.hadoop.hbase.util.HashKey<T>
    • org.apache.hadoop.hbase.util.ByteArrayHashKey
    • org.apache.hadoop.hbase.util.CellHashKey
      • org.apache.hadoop.hbase.util.RowBloomHashKey
      • org.apache.hadoop.hbase.util.RowColBloomHashKey
  • org.apache.hadoop.hbase.util.HasThread (implements java.lang.Runnable)
  • org.apache.hadoop.hbase.util.HBaseConfTool
  • org.apache.hadoop.hbase.util.HBaseFsck.CheckRegionConsistencyWorkItem (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.util.HBaseFsck.FileLockCallable (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.util.HBaseFsck.PrintingErrorReporter (implements org.apache.hadoop.hbase.util.HbckErrorReporter)
  • org.apache.hadoop.hbase.util.HBaseFsck.RegionBoundariesInformation
  • org.apache.hadoop.hbase.util.HBaseFsck.WorkItemHdfsDir (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.util.HBaseFsck.WorkItemHdfsRegionInfo (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.util.HBaseFsck.WorkItemOverlapMerge (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.util.HBaseFsck.WorkItemRegion (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.util.HBaseFsckRepair
  • org.apache.hadoop.hbase.util.HbckRegionInfo (implements org.apache.hadoop.hbase.util.KeyRange)
  • org.apache.hadoop.hbase.util.HbckRegionInfo.HdfsEntry
  • org.apache.hadoop.hbase.util.HbckRegionInfo.OnlineEntry
  • org.apache.hadoop.hbase.util.HbckTableInfo
  • org.apache.hadoop.hbase.util.HFileArchiveUtil
  • org.apache.hadoop.hbase.HRegionInfo (implements java.lang.Comparable<T>, org.apache.hadoop.hbase.client.RegionInfo)
    • org.apache.hadoop.hbase.util.HbckRegionInfo.MetaEntry
  • org.apache.hadoop.hbase.util.IdLock
  • org.apache.hadoop.hbase.util.IdLock.Entry
  • org.apache.hadoop.hbase.util.IdReadWriteLock<T>
  • org.apache.hadoop.hbase.util.ImmutableByteArray
  • org.apache.hadoop.hbase.util.IncrementingEnvironmentEdge (implements org.apache.hadoop.hbase.util.EnvironmentEdge)
  • org.apache.hadoop.hbase.util.JRubyFormat
  • org.apache.hadoop.hbase.util.JSONBean
  • org.apache.hadoop.hbase.util.JsonMapper
  • org.apache.hadoop.hbase.util.JSONMetricUtil
  • org.apache.hadoop.hbase.util.JVM
  • org.apache.hadoop.hbase.util.JVMClusterUtil
  • org.apache.hadoop.hbase.util.JvmPauseMonitor
  • org.apache.hadoop.hbase.util.JvmPauseMonitor.GcTimes
  • org.apache.hadoop.hbase.util.JvmPauseMonitor.Monitor (implements java.lang.Runnable)
  • org.apache.hadoop.hbase.util.JvmVersion
  • org.apache.hadoop.hbase.util.KeyLocker<K>
  • org.apache.hadoop.hbase.util.LossyCounting
  • org.apache.hadoop.hbase.util.ManualEnvironmentEdge (implements org.apache.hadoop.hbase.util.EnvironmentEdge)
  • org.apache.hadoop.hbase.util.MapreduceDependencyClasspathTool (implements org.apache.hadoop.util.Tool)
  • org.apache.hadoop.hbase.util.MD5Hash
  • org.apache.hadoop.hbase.util.Methods
  • org.apache.hadoop.hbase.util.ModifyRegionUtils
  • org.apache.hadoop.hbase.util.MovingAverage<T>
    • org.apache.hadoop.hbase.util.SimpleMovingAverage
    • org.apache.hadoop.hbase.util.WindowMovingAverage
      • org.apache.hadoop.hbase.util.ExponentialMovingAverage
      • org.apache.hadoop.hbase.util.WeightedMovingAverage
  • org.apache.hadoop.hbase.util.MultiHConnection
  • org.apache.hadoop.hbase.util.MunkresAssignment
  • org.apache.hadoop.hbase.util.NettyEventLoopGroupConfig
  • org.apache.hadoop.hbase.util.NonceKey
  • org.apache.hadoop.hbase.regionserver.NonLazyKeyValueScanner (implements org.apache.hadoop.hbase.regionserver.KeyValueScanner)
    • org.apache.hadoop.hbase.regionserver.NonReversedNonLazyKeyValueScanner
      • org.apache.hadoop.hbase.util.CollectionBackedScanner
  • org.apache.hadoop.hbase.util.ObjectIntPair<T>
  • org.apache.hadoop.hbase.util.ObjectPool<K,V>
    • org.apache.hadoop.hbase.util.SoftObjectPool<K,V>
    • org.apache.hadoop.hbase.util.WeakObjectPool<K,V>
  • org.apache.hadoop.hbase.util.OrderedBytes
  • org.apache.hadoop.hbase.util.Pair<T1,T2> (implements java.io.Serializable)
  • org.apache.hadoop.hbase.util.PairOfSameType<T> (implements java.lang.Iterable<T>)
  • org.apache.hadoop.hbase.util.PoolMap<K,V> (implements java.util.Map<K,V>)
  • org.apache.hadoop.hbase.util.PrettyPrinter
  • org.apache.hadoop.hbase.util.ProcessUtils
  • org.apache.hadoop.hbase.util.Random64
  • java.lang.ref.Reference<T>
    • java.lang.ref.SoftReference<T>
      • org.apache.hadoop.hbase.util.SoftObjectPool.SoftObjectReference
    • java.lang.ref.WeakReference<T>
      • org.apache.hadoop.hbase.util.WeakObjectPool.WeakObjectReference
  • org.apache.hadoop.hbase.util.ReflectionUtils
  • org.apache.hadoop.hbase.util.RegionMover.MoveWithAck (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.util.RegionMover.MoveWithoutAck (implements java.util.concurrent.Callable<V>)
  • org.apache.hadoop.hbase.util.RegionMover.RegionMoverBuilder
  • org.apache.hadoop.hbase.client.RegionReplicaUtil
    • org.apache.hadoop.hbase.util.ServerRegionReplicaUtil
  • org.apache.hadoop.hbase.util.RegionSplitCalculator<R>
  • org.apache.hadoop.hbase.util.RegionSplitter
  • org.apache.hadoop.hbase.util.RegionSplitter.NumberStringSplit (implements org.apache.hadoop.hbase.util.RegionSplitter.SplitAlgorithm)
    • org.apache.hadoop.hbase.util.RegionSplitter.DecimalStringSplit
    • org.apache.hadoop.hbase.util.RegionSplitter.HexStringSplit
  • org.apache.hadoop.hbase.util.RegionSplitter.UniformSplit (implements org.apache.hadoop.hbase.util.RegionSplitter.SplitAlgorithm)
  • org.apache.hadoop.hbase.util.RetryCounter
  • org.apache.hadoop.hbase.util.RetryCounter.BackoffPolicy
    • org.apache.hadoop.hbase.util.RetryCounter.ExponentialBackoffPolicy
      • org.apache.hadoop.hbase.util.RetryCounter.ExponentialBackoffPolicyWithLimit
  • org.apache.hadoop.hbase.util.RetryCounter.RetryConfig
  • org.apache.hadoop.hbase.util.RetryCounterFactory
  • org.apache.hadoop.hbase.util.RollingStatCalculator
  • org.apache.hadoop.hbase.util.ShutdownHookManager
    • org.apache.hadoop.hbase.util.ShutdownHookManager.ShutdownHookManagerV1
    • org.apache.hadoop.hbase.util.ShutdownHookManager.ShutdownHookManagerV2
  • org.apache.hadoop.hbase.util.Sleeper
  • org.apache.hadoop.hbase.util.SortedList<E> (implements java.util.List<E>, java.util.RandomAccess)
  • org.apache.hadoop.hbase.util.Strings
  • org.apache.hadoop.hbase.util.TableDescriptorChecker
  • org.apache.hadoop.hbase.util.hbck.TableIntegrityErrorHandlerImpl (implements org.apache.hadoop.hbase.util.hbck.TableIntegrityErrorHandler)
    • org.apache.hadoop.hbase.util.HbckTableInfo.IntegrityFixSuggester
      • org.apache.hadoop.hbase.util.HbckTableInfo.HDFSIntegrityFixer
  • java.lang.Thread (implements java.lang.Runnable)
    • org.apache.hadoop.hbase.util.JVMClusterUtil.MasterThread
    • org.apache.hadoop.hbase.util.JVMClusterUtil.RegionServerThread
  • java.lang.ThreadLocal<T>
    • org.apache.hadoop.hbase.util.PoolMap.ThreadLocalPool<R> (implements org.apache.hadoop.hbase.util.PoolMap.Pool<R>)
  • org.apache.hadoop.hbase.util.Threads
  • org.apache.hadoop.hbase.util.Threads.PrintThreadInfoLazyHolder
  • java.lang.Throwable (implements java.io.Serializable)
    • java.lang.Exception
      • org.apache.hadoop.hbase.util.CommonFSUtils.StreamLacksCapabilityException
      • java.io.IOException
        • org.apache.hadoop.hbase.util.FileSystemVersionException
        • org.apache.hadoop.hbase.HBaseIOException
          • org.apache.hadoop.hbase.util.LeaseNotRecoveredException
      • java.lang.RuntimeException
        • java.lang.UnsupportedOperationException
          • org.apache.hadoop.hbase.util.ReadOnlyByteRangeException
  • org.apache.hadoop.hbase.util.Triple<A,B,C>
  • org.apache.hadoop.hbase.util.UnsafeAccess
  • org.apache.hadoop.hbase.util.UnsafeAvailChecker
  • org.apache.hadoop.hbase.util.VersionInfo
  • org.apache.hadoop.hbase.util.Writables
  • org.apache.hadoop.hbase.util.YammerHistogramUtils
  • org.apache.hadoop.hbase.util.ZKDataMigrator

Interface Hierarchy

• org.apache.hadoop.hbase.util.Addressing.AddressSelectionCondition
• java.lang.AutoCloseable
  • java.io.Closeable
    • org.apache.hadoop.hbase.util.JSONBean.Writer
• org.apache.hadoop.hbase.util.AvlUtil.AvlInsertOrReplace<TNode>
• org.apache.hadoop.hbase.util.AvlUtil.AvlKeyComparator<TNode>
• org.apache.hadoop.hbase.util.AvlUtil.AvlNodeVisitor<TNode>
• org.apache.hadoop.hbase.util.BloomFilterBase
  • org.apache.hadoop.hbase.util.BloomFilter
  • org.apache.hadoop.hbase.util.BloomFilterWriter (also extends org.apache.hadoop.hbase.regionserver.CellSink, org.apache.hadoop.hbase.regionserver.ShipperListener)
• org.apache.hadoop.hbase.util.ByteBufferAllocator
• org.apache.hadoop.hbase.util.ByteBufferArray.Visitor
• org.apache.hadoop.hbase.util.Bytes.Comparer<T>
• org.apache.hadoop.hbase.util.CancelableProgressable
• org.apache.hadoop.hbase.regionserver.CellSink
  • org.apache.hadoop.hbase.util.BloomFilterWriter (also extends org.apache.hadoop.hbase.util.BloomFilterBase, org.apache.hadoop.hbase.regionserver.ShipperListener)
• java.lang.Comparable<T>
  • org.apache.hadoop.hbase.util.ByteRange
    • org.apache.hadoop.hbase.util.PositionedByteRange
• org.apache.hadoop.hbase.util.ConcurrentMapUtils.IOExceptionSupplier<V>
• org.apache.hadoop.hbase.util.EnvironmentEdge
• org.apache.hadoop.hbase.util.FileStatusFilter
• org.apache.hadoop.hbase.util.FSUtils.ProgressReporter
• org.apache.hadoop.hbase.util.FSVisitor.StoreFileVisitor
• org.apache.hadoop.hbase.util.HbckErrorReporter
• org.apache.hadoop.hbase.util.KeyRange
• org.apache.hadoop.hbase.util.LossyCounting.LossyCountingListener
• org.apache.hadoop.hbase.util.ModifyRegionUtils.RegionEditTask
• org.apache.hadoop.hbase.util.ModifyRegionUtils.RegionFillTask
• org.apache.hadoop.hbase.util.ObjectPool.ObjectFactory<K,V>
• org.apache.hadoop.hbase.util.PoolMap.Pool<R>
• org.apache.hadoop.hbase.util.RegionSplitter.SplitAlgorithm
• org.apache.hadoop.hbase.regionserver.ShipperListener
  • org.apache.hadoop.hbase.util.BloomFilterWriter (also extends org.apache.hadoop.hbase.util.BloomFilterBase, org.apache.hadoop.hbase.regionserver.CellSink)
• org.apache.hadoop.hbase.util.Threads.PrintThreadInfoHelper
• org.apache.hadoop.hbase.util.TimeMeasurable<T>

Enum Hierarchy

• java.lang.Object
  • java.lang.Enum<E> (implements java.lang.Comparable<T>, java.io.Serializable)
    • org.apache.hadoop.hbase.util.IdReadWriteLock.ReferenceType
    • org.apache.hadoop.hbase.util.PoolMap.PoolType
    • org.apache.hadoop.hbase.util.Order
    • org.apache.hadoop.hbase.util.HbckErrorReporter.ERROR_CODE
    • org.apache.hadoop.hbase.util.ChecksumType
    • org.apache.hadoop.hbase.util.Bytes.LexicographicalComparerHolder.PureJavaComparer (implements org.apache.hadoop.hbase.util.Bytes.Comparer<T>)
    • org.apache.hadoop.hbase.util.Bytes.LexicographicalComparerHolder.UnsafeComparer (implements org.apache.hadoop.hbase.util.Bytes.Comparer<T>)
    • org.apache.hadoop.hbase.util.PrettyPrinter.Unit