org.apache.hadoop.util
Interfaces 
Progressable
Tool
Classes 
Options
Options.BooleanOption
Options.ClassOption
Options.FSDataInputStreamOption
Options.FSDataOutputStreamOption
Options.IntegerOption
Options.LongOption
Options.PathOption
Options.ProgressableOption
Options.StringOption
ProtoUtil
PureJavaCrc32
PureJavaCrc32C
ReflectionUtils
Shell.ShellCommandExecutor
ShutdownHookManager
StringInterner
ThreadUtil
ToolRunner
Enums 
DataChecksum.Type
StringUtils.TraditionalBinaryPrefix
Exceptions 
DiskChecker.DiskErrorException
DiskChecker.DiskOutOfSpaceException
ExitUtil.ExitException
Shell.ExitCodeException