| Interface | Description | 
|---|---|
| Clock | 
 An interface to represent clocks, so that they can be mocked out in unit tests. 
 | 
| CommandLineLoggingUtils | |
| CommandLineUtils | 
 Contains basic command line parsing functionality and methods to parse some common Spark CLI
 options. 
 | 
| JsonUtils | |
| KnownSizeEstimation | 
 A trait that allows a class to give  
SizeEstimator more accurate size estimation. | 
| ListenerBus<L,E> | 
 An event bus which posts events to its listeners. 
 | 
| SparkClassUtils | |
| SparkErrorUtils | |
| SparkFileUtils | |
| SparkSerDeUtils | |
| TaskCompletionListener | 
 :: DeveloperApi :: 
 | 
| TaskFailureListener | 
 :: DeveloperApi :: 
 | 
| Class | Description | 
|---|---|
| AccumulatorContext | 
 An internal class used to track accumulators by Spark itself. 
 | 
| AccumulatorV2<IN,OUT> | 
 The base class for accumulators, that can accumulate inputs of type  
IN, and produce output of
 type OUT. | 
| CausedBy | 
 Extractor Object for pulling out the root cause of an error. 
 | 
| ChildFirstURLClassLoader | 
 A mutable class loader that gives preference to its own URLs over the parent class loader
 when loading classes and resources. 
 | 
| ClosureCleaner | 
 A cleaner that renders closures serializable if they can be done so safely. 
 | 
| CollectionAccumulator<T> | 
 An  
accumulator for collecting a list of elements. | 
| CollectionsUtils | |
| DependencyUtils | |
| DoubleAccumulator | 
 An  
accumulator for computing sum, count, and averages for double precision
 floating numbers. | 
| EnumUtil | |
| HadoopFSUtils | 
 Utility functions to simplify and speed-up file listing. 
 | 
| IndylambdaScalaClosures | |
| InnerClosureFinder | |
| IntParam | 
 An extractor object for parsing strings into integers. 
 | 
| Iterators | |
| JsonProtocol | 
 Serializes SparkListener events to/from JSON. 
 | 
| LongAccumulator | 
 An  
accumulator for computing sum, count, and average of 64-bit integers. | 
| MemoryParam | 
 An extractor object for parsing JVM memory strings, such as "10g", into an Int representing
 the number of megabytes. 
 | 
| MethodIdentifier<T> | 
 Helper class to identify a method. 
 | 
| MutablePair<T1,T2> | 
 :: DeveloperApi ::
 A tuple of 2 elements. 
 | 
| MutableURLClassLoader | 
 URL class loader that exposes the `addURL` method in URLClassLoader. 
 | 
| ParentClassLoader | 
 A class loader which makes some protected methods in ClassLoader accessible. 
 | 
| ReturnStatementFinder | |
| RpcUtils | |
| SecurityUtils | 
 Various utility methods used by Spark Security. 
 | 
| SerializableConfiguration | 
 Hadoop configuration but serializable. 
 | 
| ShutdownHookManager | 
 Various utility methods used by Spark. 
 | 
| SignalUtils | 
 Contains utilities for working with posix signals. 
 | 
| SizeEstimator | 
 :: DeveloperApi ::
 Estimates the sizes of Java objects (number of bytes of memory they occupy), for use in
 memory-aware caches. 
 | 
| SparkExitCode | |
| SparkSchemaUtils | 
 Utils for handling schemas. 
 | 
| SparkShutdownHook | |
| SparkThreadUtils | |
| StatCounter | 
 A class for tracking the statistics of a set of numbers (count, mean and variance) in a
 numerically robust way. 
 | 
| ThreadUtils | |
| Utils | 
 Various utility methods used by Spark. 
 | 
| VersionUtils | 
 Utilities for working with Spark version strings 
 |