| Package | Description | 
|---|---|
| java.awt | Contains all of the classes for creating user
interfaces and for painting graphics and images. | 
| java.io | Provides for system input and output through data streams,
serialization and the file system. | 
| java.lang | Provides classes that are fundamental to the design of the Java
 programming language. | 
| java.nio.file | Defines interfaces and classes for the Java virtual machine to access files,
 file attributes, and file systems. | 
| java.time.temporal | 
 Access to date and time using fields and units, and date time adjusters. | 
| java.util | Contains the collections framework, legacy collection classes, event model,
date and time facilities, internationalization, and miscellaneous utility
classes (a string tokenizer, a random-number generator, and a bit array). | 
| java.util.concurrent | Utility classes commonly useful in concurrent programming. | 
| java.util.function | Functional interfaces provide target types for lambda expressions
 and method references. | 
| java.util.logging | 
Provides the classes and interfaces of 
the JavaTM 2
 platform's core logging facilities. | 
| java.util.prefs | This package allows applications to store and retrieve user and system
preference and configuration data. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | KeyEventDispatcherA KeyEventDispatcher cooperates with the current KeyboardFocusManager in the
 targeting and dispatching of all KeyEvents. | 
| interface  | KeyEventPostProcessorA KeyEventPostProcessor cooperates with the current KeyboardFocusManager
 in the final resolution of all unconsumed KeyEvents. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | FileFilterA filter for abstract pathnames. | 
| interface  | FilenameFilterInstances of classes that implement this interface are used to
 filter filenames. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | RunnableThe  Runnableinterface should be implemented by any
 class whose instances are intended to be executed by a thread. | 
| static interface  | Thread.UncaughtExceptionHandlerInterface for handlers invoked when a Thread abruptly
 terminates due to an uncaught exception. | 
| Modifier and Type | Interface and Description | 
|---|---|
| static interface  | DirectoryStream.Filter<T>An interface that is implemented by objects that decide if a directory
 entry should be accepted or filtered. | 
| interface  | PathMatcherAn interface that is implemented by objects that perform match operations on
 paths. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | TemporalAdjusterStrategy for adjusting a temporal object. | 
| interface  | TemporalQuery<R>Strategy for querying a temporal object. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | Comparator<T>A comparison function, which imposes a total ordering on some
 collection of objects. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | Callable<V>A task that returns a result and may throw an exception. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | BiConsumer<T,U>Represents an operation that accepts two input arguments and returns no
 result. | 
| interface  | BiFunction<T,U,R>Represents a function that accepts two arguments and produces a result. | 
| interface  | BinaryOperator<T>Represents an operation upon two operands of the same type, producing a result
 of the same type as the operands. | 
| interface  | BiPredicate<T,U>Represents a predicate (boolean-valued function) of two arguments. | 
| interface  | BooleanSupplierRepresents a supplier of  boolean-valued results. | 
| interface  | Consumer<T>Represents an operation that accepts a single input argument and returns no
 result. | 
| interface  | DoubleBinaryOperatorRepresents an operation upon two  double-valued operands and producing adouble-valued result. | 
| interface  | DoubleConsumerRepresents an operation that accepts a single  double-valued argument and
 returns no result. | 
| interface  | DoubleFunction<R>Represents a function that accepts a double-valued argument and produces a
 result. | 
| interface  | DoublePredicateRepresents a predicate (boolean-valued function) of one  double-valued
 argument. | 
| interface  | DoubleSupplierRepresents a supplier of  double-valued results. | 
| interface  | DoubleToIntFunctionRepresents a function that accepts a double-valued argument and produces an
 int-valued result. | 
| interface  | DoubleToLongFunctionRepresents a function that accepts a double-valued argument and produces a
 long-valued result. | 
| interface  | DoubleUnaryOperatorRepresents an operation on a single  double-valued operand that produces
 adouble-valued result. | 
| interface  | Function<T,R>Represents a function that accepts one argument and produces a result. | 
| interface  | IntBinaryOperatorRepresents an operation upon two  int-valued operands and producing anint-valued result. | 
| interface  | IntConsumerRepresents an operation that accepts a single  int-valued argument and
 returns no result. | 
| interface  | IntFunction<R>Represents a function that accepts an int-valued argument and produces a
 result. | 
| interface  | IntPredicateRepresents a predicate (boolean-valued function) of one  int-valued
 argument. | 
| interface  | IntSupplierRepresents a supplier of  int-valued results. | 
| interface  | IntToDoubleFunctionRepresents a function that accepts an int-valued argument and produces a
 double-valued result. | 
| interface  | IntToLongFunctionRepresents a function that accepts an int-valued argument and produces a
 long-valued result. | 
| interface  | IntUnaryOperatorRepresents an operation on a single  int-valued operand that produces
 anint-valued result. | 
| interface  | LongBinaryOperatorRepresents an operation upon two  long-valued operands and producing along-valued result. | 
| interface  | LongConsumerRepresents an operation that accepts a single  long-valued argument and
 returns no result. | 
| interface  | LongFunction<R>Represents a function that accepts a long-valued argument and produces a
 result. | 
| interface  | LongPredicateRepresents a predicate (boolean-valued function) of one  long-valued
 argument. | 
| interface  | LongSupplierRepresents a supplier of  long-valued results. | 
| interface  | LongToDoubleFunctionRepresents a function that accepts a long-valued argument and produces a
 double-valued result. | 
| interface  | LongToIntFunctionRepresents a function that accepts a long-valued argument and produces an
 int-valued result. | 
| interface  | LongUnaryOperatorRepresents an operation on a single  long-valued operand that produces
 along-valued result. | 
| interface  | ObjDoubleConsumer<T>Represents an operation that accepts an object-valued and a
  double-valued argument, and returns no result. | 
| interface  | ObjIntConsumer<T>Represents an operation that accepts an object-valued and a
  int-valued argument, and returns no result. | 
| interface  | ObjLongConsumer<T>Represents an operation that accepts an object-valued and a
  long-valued argument, and returns no result. | 
| interface  | Predicate<T>Represents a predicate (boolean-valued function) of one argument. | 
| interface  | Supplier<T>Represents a supplier of results. | 
| interface  | ToDoubleBiFunction<T,U>Represents a function that accepts two arguments and produces a double-valued
 result. | 
| interface  | ToDoubleFunction<T>Represents a function that produces a double-valued result. | 
| interface  | ToIntBiFunction<T,U>Represents a function that accepts two arguments and produces an int-valued
 result. | 
| interface  | ToIntFunction<T>Represents a function that produces an int-valued result. | 
| interface  | ToLongBiFunction<T,U>Represents a function that accepts two arguments and produces a long-valued
 result. | 
| interface  | ToLongFunction<T>Represents a function that produces a long-valued result. | 
| interface  | UnaryOperator<T>Represents an operation on a single operand that produces a result of the
 same type as its operand. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | FilterA Filter can be used to provide fine grain control over
 what is logged, beyond the control provided by log levels. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | PreferenceChangeListenerA listener for receiving preference change events. | 
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