Package org.apache.hadoop.util


package org.apache.hadoop.util
Common utilities.
  • Class
    Description
    A URLClassLoader for application isolation.
    org.apache.hadoop.util.AsyncDiskService
     
    org.apache.hadoop.util.AutoCloseableLock
    This is a wrap class of a ReentrantLock.
    org.apache.hadoop.util.BasicDiskValidator
    BasicDiskValidator is a wrapper around DiskChecker.
    org.apache.hadoop.util.BlockingThreadPoolExecutorService
    This ExecutorService blocks the submission of new tasks when its queue is already full by using a semaphore.
    org.apache.hadoop.util.CacheableIPList
    CacheableIPList loads a list of subnets from a file.
    org.apache.hadoop.util.ChunkedArrayList<T>
    Simplified List implementation which stores elements as a list of chunks, each chunk having a maximum size.
    org.apache.hadoop.util.Classpath
    Command-line utility for getting the full classpath needed to launch a Hadoop client application.
    org.apache.hadoop.util.ClassUtil
     
    org.apache.hadoop.util.CleanerUtil
    sun.misc.Cleaner has moved in OpenJDK 9 and sun.misc.Unsafe#invokeCleaner(ByteBuffer) is the replacement.
    org.apache.hadoop.util.CleanerUtil.BufferCleaner
    Pass in an implementation of this interface to cleanup ByteBuffers.
    org.apache.hadoop.util.CloseableReferenceCount
    A closeable object that maintains a reference count.
    org.apache.hadoop.util.CombinedIPList
    Util class to stores ips/hosts/subnets.
    org.apache.hadoop.util.CombinedIPWhiteList
     
    org.apache.hadoop.util.ComparableVersion
    Generic implementation of version comparison.
    org.apache.hadoop.util.ConfigurationHelper
    Configuration Helper class to provide advanced configuration parsing.
    org.apache.hadoop.util.ConfTest
    This class validates configuration XML files in ${HADOOP_CONF_DIR} or specified ones.
    org.apache.hadoop.util.CpuTimeTracker
    Utility for sampling and computing CPU usage.
    org.apache.hadoop.util.CrcComposer
    Encapsulates logic for composing multiple CRCs into one or more combined CRCs corresponding to concatenated underlying data ranges.
    org.apache.hadoop.util.CrcUtil
    This class provides utilities for working with CRCs.
    org.apache.hadoop.util.Daemon
    A thread that has called Thread.setDaemon(boolean) with true.
    org.apache.hadoop.util.Daemon.DaemonFactory
    Provide a factory for named daemon threads, for use in ExecutorServices constructors
    org.apache.hadoop.util.DataChecksum
    This class provides interface and utilities for processing checksums for DFS data transfers.
    The checksum types
    org.apache.hadoop.util.DirectBufferPool
    A simple class for pooling direct ByteBuffers.
    org.apache.hadoop.util.DiskChecker
    Class that provides utility functions for checking disk problem
    org.apache.hadoop.util.DiskChecker.DiskErrorException
     
    org.apache.hadoop.util.DiskChecker.DiskOutOfSpaceException
     
    org.apache.hadoop.util.DiskValidator
    A interface for disk validators.
    org.apache.hadoop.util.DiskValidatorFactory
    The factory class to create instance of DiskValidator.
    A duration with logging of final state at info or debug in the close() call.
    org.apache.hadoop.util.ExitCodeProvider
    Get the exit code of an exception.
    org.apache.hadoop.util.ExitUtil
    Facilitates hooking process termination for tests, debugging and embedding.
    org.apache.hadoop.util.ExitUtil.ExitException
    An exception raised when a call to ExitUtil.terminate(int) was called and system exits were blocked.
    org.apache.hadoop.util.ExitUtil.HaltException
    An exception raised when a call to ExitUtil.terminate(int) was called and system halts were blocked.
    org.apache.hadoop.util.FastNumberFormat
    Fast thread-safe version of NumberFormat
    org.apache.hadoop.util.FileBasedIPList
    FileBasedIPList loads a list of subnets in CIDR format and ip addresses from a file.
    org.apache.hadoop.util.FindClass
    This entry point exists for diagnosing classloader problems: is a class or resource present -and if so, where?
    org.apache.hadoop.util.GcTimeMonitor
    This class monitors the percentage of time the JVM is paused in GC within the specified observation window, say 1 minute.
    org.apache.hadoop.util.GcTimeMonitor.Builder
     
    org.apache.hadoop.util.GcTimeMonitor.GcData
    Encapsulates data about GC pauses measured at the specific timestamp.
    org.apache.hadoop.util.GcTimeMonitor.GcTimeAlertHandler
    The user can provide an instance of a class implementing this interface when initializing a GcTimeMonitor to receive alerts when GC time percentage exceeds the specified threshold.
    org.apache.hadoop.util.GenericOptionsParser
    GenericOptionsParser is a utility to parse command line arguments generic to the Hadoop framework.
    org.apache.hadoop.util.GenericsUtil
    Contains utility methods for dealing with Java Generics.
    org.apache.hadoop.util.GSet<K,E extends K>
    A GSet is set, which supports the GSet.get(Object) operation.
    org.apache.hadoop.util.GSetByHashMap<K,E extends K>
    A GSet implementation by HashMap.
    org.apache.hadoop.util.HeapSort
    An implementation of the core algorithm of HeapSort.
    org.apache.hadoop.util.HostsFileReader
     
    org.apache.hadoop.util.HostsFileReader.HostDetails
    An atomic view of the included and excluded hosts
    org.apache.hadoop.util.HttpExceptionUtils
    HTTP utility class to help propagate server side exception to the client over HTTP as a JSON payload.
    org.apache.hadoop.util.IdentityHashStore<K,V>
    The IdentityHashStore stores (key, value) mappings in an array.
    org.apache.hadoop.util.IdentityHashStore.Visitor<K,V>
     
    org.apache.hadoop.util.IdGenerator
    Generic ID generator used for generating various types of number sequences.
    org.apache.hadoop.util.IndexedSortable
    Interface for collections capable of being sorted by IndexedSorter algorithms.
    org.apache.hadoop.util.IndexedSorter
    Interface for sort algorithms accepting IndexedSortable items.
    org.apache.hadoop.util.InstrumentedLock
    This is a debugging class that can be used by callers to track whether a specific lock is being held for too long and periodically log a warning and stack trace, if so.
    org.apache.hadoop.util.InstrumentedLock.SuppressedSnapshot
    Immutable class to capture a snapshot of suppressed log message stats.
    org.apache.hadoop.util.InstrumentedReadLock
    This is a wrap class of a ReadLock.
    org.apache.hadoop.util.InstrumentedReadWriteLock
    This is a wrap class of a ReentrantReadWriteLock.
    org.apache.hadoop.util.InstrumentedWriteLock
    This is a wrap class of a WriteLock.
    org.apache.hadoop.util.IntrusiveCollection<E extends org.apache.hadoop.util.IntrusiveCollection.Element>
    Implements an intrusive doubly-linked list.
    org.apache.hadoop.util.IntrusiveCollection.Element
    An element contained in this list.
    org.apache.hadoop.util.InvalidChecksumSizeException
    Thrown when bytesPerChecksun field in the meta file is less than or equal to 0 or type is invalid.
     
    org.apache.hadoop.util.JsonSerialization<T>
    Support for marshalling objects to and from JSON.
    org.apache.hadoop.util.JvmPauseMonitor
    Class which sets up a simple thread which runs in a loop sleeping for a short interval of time.
    org.apache.hadoop.util.KMSUtil
    Utils for KMS.
    org.apache.hadoop.util.LambdaUtils
    Lambda-expression utilities be they generic or specific to Hadoop datatypes.
    org.apache.hadoop.util.LightWeightCache<K,E extends K>
    A low memory footprint Cache which extends LightWeightGSet.
    org.apache.hadoop.util.LightWeightCache.Entry
    Entries of LightWeightCache.
    org.apache.hadoop.util.LightWeightGSet<K,E extends K>
    A low memory footprint GSet implementation, which uses an array for storing the elements and linked lists for collision resolution.
    org.apache.hadoop.util.LightWeightGSet.LinkedElement
    Elements of LightWeightGSet.
    org.apache.hadoop.util.LightWeightResizableGSet<K,E extends K>
    A low memory footprint GSet implementation, which uses an array for storing the elements and linked lists for collision resolution.
    org.apache.hadoop.util.LimitInputStream
    Copied from guava source code v15 (LimitedInputStream) Guava deprecated LimitInputStream in v14 and removed it in v15.
    org.apache.hadoop.util.LineReader
    A class that provides a line reader from an input stream.
    org.apache.hadoop.util.Lists
    Static utility methods pertaining to List instances.
    org.apache.hadoop.util.MachineList
    Container class which holds a list of ip/host addresses and answers membership queries.
    org.apache.hadoop.util.MachineList.InetAddressFactory
    InetAddressFactory is used to obtain InetAddress from host.
    org.apache.hadoop.util.MergeSort
    An implementation of the core algorithm of MergeSort.
    org.apache.hadoop.util.NativeCodeLoader
    A helper to load the native hadoop code i.e. libhadoop.so.
    org.apache.hadoop.util.NativeLibraryChecker
     
    Little duration counter.
    org.apache.hadoop.util.Options
    This class allows generic access to variable length type-safe parameter lists.
    org.apache.hadoop.util.Options.BooleanOption
     
    org.apache.hadoop.util.Options.ClassOption
     
    org.apache.hadoop.util.Options.FSDataInputStreamOption
     
    org.apache.hadoop.util.Options.FSDataOutputStreamOption
     
    org.apache.hadoop.util.Options.IntegerOption
     
    org.apache.hadoop.util.Options.LongOption
     
    org.apache.hadoop.util.Options.PathOption
     
    org.apache.hadoop.util.Options.ProgressableOption
     
    org.apache.hadoop.util.Options.StringOption
     
    org.apache.hadoop.util.PerformanceAdvisory
     
    org.apache.hadoop.util.PlatformName
    A helper class for getting build-info of the java-vm.
    org.apache.hadoop.util.Preconditions
    This class replaces guava.Preconditions which provides helpers to validate the following conditions: An invalid null obj causes a NullPointerException. An invalid argument causes an IllegalArgumentException. An invalid state causes an IllegalStateException. An invalid index causes an IndexOutOfBoundsException.
    org.apache.hadoop.util.PrintJarMainClass
    A micro-application that prints the main class name out of a jar file.
    org.apache.hadoop.util.PriorityQueue<T>
    A PriorityQueue maintains a partial ordering of its elements such that the least element can always be found in constant time.
    org.apache.hadoop.util.ProcessUtils
    Process related utilities.
    org.apache.hadoop.util.ProgramDriver
    A driver that is used to run programs added to it
    org.apache.hadoop.util.Progress
    Utility to assist with generation of progress reports.
    A facility for reporting progress.
    org.apache.hadoop.util.ProtoUtil
     
    A pure-java implementation of the CRC32 checksum that uses the same polynomial as the built-in native CRC32.
    A pure-java implementation of the CRC32 checksum that uses the CRC32-C polynomial, the same polynomial used by iSCSI and implemented on many Intel chipsets supporting SSE4.2.
    org.apache.hadoop.util.QuickSort
    An implementation of the core algorithm of QuickSort.
    org.apache.hadoop.util.RateLimiting
    Minimal subset of google rate limiter class.
    org.apache.hadoop.util.RateLimitingFactory
    Factory for Rate Limiting.
    org.apache.hadoop.util.ReadWriteDiskValidator
    ReadWriteDiskValidator is the class to check a directory by to create a file, write some bytes into it, read back, and verify if they are identical.
    org.apache.hadoop.util.ReadWriteDiskValidatorMetrics
    The metrics for a directory generated by ReadWriteDiskValidator.
    General reflection utils
    org.apache.hadoop.util.RunJar
    Run a Hadoop job jar.
    org.apache.hadoop.util.SemaphoredDelegatingExecutor
    This ExecutorService blocks the submission of new tasks when its queue is already full by using a semaphore.
    org.apache.hadoop.util.SequentialNumber
    Sequential number generator.
    org.apache.hadoop.util.ServicePlugin
    Service plug-in interface.
    org.apache.hadoop.util.ServletUtil
     
    org.apache.hadoop.util.Sets
    Static utility methods pertaining to Set instances.
    A base class for running a Shell command.
    org.apache.hadoop.util.Shell.CommandExecutor
     
    org.apache.hadoop.util.Shell.ExitCodeException
    This is an IOException with exit code added.
     
    org.apache.hadoop.util.Shell.ShellCommandExecutor
    A simple shell command executor.
    The ShutdownHookManager enables running shutdownHook in a deterministic order, higher priority first.
    org.apache.hadoop.util.ShutdownThreadsHelper
    Helper class to shutdown Threads and ExecutorServices.
    org.apache.hadoop.util.SignalLogger
    This class logs a message whenever we're about to exit on a UNIX signal.
    org.apache.hadoop.util.SignalUtil
     
    org.apache.hadoop.util.SignalUtil.Handler
     
    org.apache.hadoop.util.SignalUtil.Signal
     
    org.apache.hadoop.util.StopWatch
    A simplified StopWatch implementation which can measure times in nanoseconds.
    Provides string interning utility methods.
    org.apache.hadoop.util.StringUtils
    General string utils
    The traditional binary prefixes, kilo, mega, ..., exa, which can be represented by a 64-bit integer.
    Plugin to calculate resource information on the system.
    org.apache.hadoop.util.SysInfoLinux
    Plugin to calculate resource information on Linux systems.
    org.apache.hadoop.util.SysInfoWindows
    Plugin to calculate resource information on Windows systems.
    org.apache.hadoop.util.ThreadUtil
     
    org.apache.hadoop.util.Time
    Utility methods for getting the time and computing intervals.
    org.apache.hadoop.util.Timer
    Utility methods for getting the time and computing intervals.
    A tool interface that supports handling of generic command-line options.
    A utility to help run Tools.
    org.apache.hadoop.util.UTF8ByteArrayUtils
     
    This class returns build information about Hadoop components.
    org.apache.hadoop.util.VersionUtil
    A wrapper class to maven's ComparableVersion class, to comply with maven's version name string convention
    org.apache.hadoop.util.Waitable<T>
    Represents an object that you can wait for.
    org.apache.hadoop.util.WeakReferenceMap<K,V>
    A map of keys type K to objects of type V which uses weak references, so does lot leak memory through long-lived references at the expense of losing references when GC takes place..
    org.apache.hadoop.util.XMLUtils
    General xml utilities.
    org.apache.hadoop.util.ZKUtil
    Utilities for working with ZooKeeper.
    org.apache.hadoop.util.ZKUtil.BadAclFormatException
     
    org.apache.hadoop.util.ZKUtil.BadAuthFormatException
     
    org.apache.hadoop.util.ZKUtil.ZKAuthInfo
    An authentication token passed to ZooKeeper.addAuthInfo