Uses of Interface java.util.Set (Java Platform SE 8 )
Date: 2026-03-16

## Uses of Interface
java.util.Set

- Packages that use Set
  Package | Description
  --- | ---
  java.awt | Contains all of the classes for creating user interfaces and for painting graphics and images.
  java.awt.font | Provides classes and interface relating to fonts.
  java.lang.management | Provides the management interfaces for monitoring and management of the Java virtual machine and other components in the Java runtime.
  java.nio.channels | Defines channels, which represent connections to entities that are capable of performing I/O operations, such as files and sockets; defines selectors, for multiplexed, non-blocking I/O operations.
  java.nio.channels.spi | Service-provider classes for the ``java.nio.channels`` package.
  java.nio.charset | Defines charsets, decoders, and encoders, for translating between bytes and Unicode characters.
  java.nio.file | Defines interfaces and classes for the Java virtual machine to access files, file attributes, and file systems.
  java.nio.file.attribute | Interfaces and classes providing access to file and file system attributes.
  java.nio.file.spi | Service-provider classes for the ``java.nio.file`` package.
  java.security | Provides the classes and interfaces for the security framework.
  java.security.cert | Provides classes and interfaces for parsing and managing certificates, certificate revocation lists (CRLs), and certification paths.
  java.text | Provides classes and interfaces for handling text, dates, numbers, and messages in a manner independent of natural languages.
  java.time | The main API for dates, times, instants, and durations.
  java.time.chrono | Generic API for calendar systems other than the default ISO.
  java.time.format | Provides classes to print and parse dates and times.
  java.time.zone | Support for time-zones and their rules.
  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.jar | Provides classes for reading and writing the JAR (Java ARchive) file format, which is based on the standard ZIP file format with an optional manifest file.
  java.util.stream | Classes to support functional-style operations on streams of elements, such as map-reduce transformations on collections.
  javax.annotation.processing | Facilities for declaring annotation processors and for allowing annotation processors to communicate with an annotation processing tool environment.
  javax.imageio | The main package of the Java Image I/O API.
  javax.lang.model.element | Interfaces used to model elements of the Java programming language.
  javax.lang.model.util | Utilities to assist in the processing of program elements and types.
  javax.management | Provides the core classes for the Java Management Extensions.
  javax.management.loading | Provides the classes which implement advanced dynamic loading.
  javax.management.openmbean | Provides the open data types and Open MBean descriptor classes.
  javax.management.remote.rmi | The RMI connector is a connector for the JMX Remote API that uses RMI to transmit client requests to a remote MBean server.
  javax.print.attribute.standard | Package javax.print.attribute.standard contains classes for specific printing attributes.
  javax.script | The scripting API consists of interfaces and classes that define Java TM Scripting Engines and provides a framework for their use in Java applications.
  javax.security.auth | This package provides a framework for authentication and authorization.
  javax.swing | Provides a set of "lightweight" (all-Java language) components that, to the maximum degree possible, work the same on all platforms.
  javax.tools | Provides interfaces for tools which can be invoked from a program, for example, compilers.
  javax.xml.ws | This package contains the core JAX-WS APIs.
  javax.xml.ws.handler.soap | This package defines APIs for SOAP message handlers.
  javax.xml.ws.soap | This package defines APIs specific to the SOAP binding.
  javax.xml.ws.spi.http | Provides HTTP SPI that is used for portable deployment of JAX-WS web services in containers(for e.g.

- - ### Uses of Set in java.awt

    Methods in java.awt that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Map.Entry<Object,Object>>` | RenderingHints.`entrySet()` Returns a `Set` view of the mappings contained in this `RenderingHints`.
    `Set<AWTKeyStroke>` | KeyboardFocusManager.`getDefaultFocusTraversalKeys(int id)` Returns a Set of default focus traversal keys for a given traversal operation.
    `Set<AWTKeyStroke>` | Container.`getFocusTraversalKeys(int id)` Returns the Set of focus traversal keys for a given traversal operation for this Container.
    `Set<AWTKeyStroke>` | Window.`getFocusTraversalKeys(int id)` Gets a focus traversal key for this Window.
    `Set<AWTKeyStroke>` | Component.`getFocusTraversalKeys(int id)` Returns the Set of focus traversal keys for a given traversal operation for this Component.
    `Set<Object>` | RenderingHints.`keySet()` Returns a `Set` view of the Keys contained in this `RenderingHints`.

    Methods in java.awt with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `void` | KeyboardFocusManager.`setDefaultFocusTraversalKeys(int id, Set<? extends AWTKeyStroke> keystrokes)` Sets the default focus traversal keys for a given traversal operation.
    `void` | Container.`setFocusTraversalKeys(int id, Set<? extends AWTKeyStroke> keystrokes)` Sets the focus traversal keys for a given traversal operation for this Container.
    `void` | Component.`setFocusTraversalKeys(int id, Set<? extends AWTKeyStroke> keystrokes)` Sets the focus traversal keys for a given traversal operation for this Component.

  - ### Uses of Set in java.awt.font

    Methods in java.awt.font that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<NumericShaper.Range>` | NumericShaper.`getRangeSet()` Returns a `Set` representing all the Unicode ranges in this `NumericShaper` that will be shaped.

    Methods in java.awt.font with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `static NumericShaper` | NumericShaper.`getContextualShaper(Set<NumericShaper.Range> ranges)` Returns a contextual shaper for the provided Unicode range(s).
    `static NumericShaper` | NumericShaper.`getContextualShaper(Set<NumericShaper.Range> ranges, NumericShaper.Range defaultContext)` Returns a contextual shaper for the provided Unicode range(s).

  - ### Uses of Set in java.lang.management

    Methods in java.lang.management that return Set
    Modifier and Type | Method and Description
    --- | ---
    `static Set<Class<? extends PlatformManagedObject>>` | ManagementFactory.`getPlatformManagementInterfaces()` Returns the set of `Class` objects, subinterface of `PlatformManagedObject`, representing all management interfaces for monitoring and managing the Java platform.

  - ### Uses of Set in java.nio.channels

    Methods in java.nio.channels that return Set
    Modifier and Type | Method and Description
    --- | ---
    `abstract Set<SelectionKey>` | Selector.`keys()` Returns this selector's key set.
    `abstract Set<SelectionKey>` | Selector.`selectedKeys()` Returns this selector's selected-key set.
    `Set<SocketOption<?>>` | NetworkChannel.`supportedOptions()` Returns a set of the socket options supported by this channel.

    Methods in java.nio.channels with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `static AsynchronousFileChannel` | AsynchronousFileChannel.`open(Path file, Set<? extends OpenOption> options, ExecutorService executor, FileAttribute<?>... attrs)` Opens or creates a file for reading and/or writing, returning an asynchronous file channel to access the file.
    `static FileChannel` | FileChannel.`open(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs)` Opens or creates a file, returning a file channel to access the file.

  - ### Uses of Set in java.nio.channels.spi

    Methods in java.nio.channels.spi that return Set
    Modifier and Type | Method and Description
    --- | ---
    `protected Set<SelectionKey>` | AbstractSelector.`cancelledKeys()` Retrieves this selector's cancelled-key set.

  - ### Uses of Set in java.nio.charset

    Methods in java.nio.charset that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<String>` | Charset.`aliases()` Returns a set containing this charset's aliases.

  - ### Uses of Set in java.nio.file

    Methods in java.nio.file that return Set
    Modifier and Type | Method and Description
    --- | ---
    `static Set<PosixFilePermission>` | Files.`getPosixFilePermissions(Path path, LinkOption... options)` Returns a file's POSIX file permissions.
    `abstract Set<String>` | FileSystem.`supportedFileAttributeViews()` Returns the set of the `names` of the file attribute views supported by this `FileSystem`.

    Methods in java.nio.file with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `static SeekableByteChannel` | Files.`newByteChannel(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs)` Opens or creates a file, returning a seekable byte channel to access the file.
    `SeekableByteChannel` | SecureDirectoryStream.`newByteChannel(T path, Set<? extends OpenOption> options, FileAttribute<?>... attrs)` Opens or creates a file in this directory, returning a seekable byte channel to access the file.
    `static Path` | Files.`setPosixFilePermissions(Path path, Set<PosixFilePermission> perms)` Sets a file's POSIX permissions.
    `static Path` | Files.`walkFileTree(Path start, Set<FileVisitOption> options, int maxDepth, FileVisitor<? super Path> visitor)` Walks a file tree.

  - ### Uses of Set in java.nio.file.attribute

    Methods in java.nio.file.attribute that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<AclEntryFlag>` | AclEntry.`flags()` Returns a copy of the flags component.
    `static Set<PosixFilePermission>` | PosixFilePermissions.`fromString(String perms)` Returns the set of permissions corresponding to a given `String` representation.
    `Set<AclEntryPermission>` | AclEntry.`permissions()` Returns a copy of the permissions component.
    `Set<PosixFilePermission>` | PosixFileAttributes.`permissions()` Returns the permissions of the file.

    Methods in java.nio.file.attribute that return types with arguments of type Set
    Modifier and Type | Method and Description
    --- | ---
    `static FileAttribute<Set<PosixFilePermission>>` | PosixFilePermissions.`asFileAttribute(Set<PosixFilePermission> perms)` Creates a `FileAttribute`, encapsulating a copy of the given file permissions, suitable for passing to the `createFile` or `createDirectory` methods.

    Methods in java.nio.file.attribute with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `static FileAttribute<Set<PosixFilePermission>>` | PosixFilePermissions.`asFileAttribute(Set<PosixFilePermission> perms)` Creates a `FileAttribute`, encapsulating a copy of the given file permissions, suitable for passing to the `createFile` or `createDirectory` methods.
    `AclEntry.Builder` | AclEntry.Builder.`setFlags(Set<AclEntryFlag> flags)` Sets the flags component of this builder.
    `AclEntry.Builder` | AclEntry.Builder.`setPermissions(Set<AclEntryPermission> perms)` Sets the permissions component of this builder.
    `void` | PosixFileAttributeView.`setPermissions(Set<PosixFilePermission> perms)` Updates the file permissions.
    `static String` | PosixFilePermissions.`toString(Set<PosixFilePermission> perms)` Returns the `String` representation of a set of permissions.

  - ### Uses of Set in java.nio.file.spi

    Methods in java.nio.file.spi with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `AsynchronousFileChannel` | FileSystemProvider.`newAsynchronousFileChannel(Path path, Set<? extends OpenOption> options, ExecutorService executor, FileAttribute<?>... attrs)` Opens or creates a file for reading and/or writing, returning an asynchronous file channel to access the file.
    `abstract SeekableByteChannel` | FileSystemProvider.`newByteChannel(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs)` Opens or creates a file, returning a seekable byte channel to access the file.
    `FileChannel` | FileSystemProvider.`newFileChannel(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs)` Opens or creates a file for reading and/or writing, returning a file channel to access the file.

  - ### Uses of Set in java.security

    Methods in java.security that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Map.Entry<Object,Object>>` | Provider.`entrySet()` Returns an unmodifiable Set view of the property entries contained in this Provider.
    `static Set<String>` | Security.`getAlgorithms(String serviceName)` Returns a Set of Strings containing the names of all available algorithms or types for the specified Java cryptographic service (e.g., Signature, MessageDigest, Cipher, Mac, KeyStore).
    `default Set<KeyStore.Entry.Attribute>` | KeyStore.Entry.`getAttributes()` Retrieves the attributes associated with an entry.
    `Set<KeyStore.Entry.Attribute>` | KeyStore.PrivateKeyEntry.`getAttributes()` Retrieves the attributes associated with an entry.
    `Set<KeyStore.Entry.Attribute>` | KeyStore.SecretKeyEntry.`getAttributes()` Retrieves the attributes associated with an entry.
    `Set<KeyStore.Entry.Attribute>` | KeyStore.TrustedCertificateEntry.`getAttributes()` Retrieves the attributes associated with an entry.
    `Set<Provider.Service>` | Provider.`getServices()` Get an unmodifiable Set of all services supported by this Provider.
    `Set<Object>` | Provider.`keySet()` Returns an unmodifiable Set view of the property keys contained in this provider.

    Methods in java.security with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `boolean` | AlgorithmConstraints.`permits(Set<CryptoPrimitive> primitives, Key key)` Determines whether a key is granted permission for the specified cryptographic primitives.
    `boolean` | AlgorithmConstraints.`permits(Set<CryptoPrimitive> primitives, String algorithm, AlgorithmParameters parameters)` Determines whether an algorithm is granted permission for the specified cryptographic primitives.
    `boolean` | AlgorithmConstraints.`permits(Set<CryptoPrimitive> primitives, String algorithm, Key key, AlgorithmParameters parameters)` Determines whether an algorithm and the corresponding key are granted permission for the specified cryptographic primitives.

    Constructors in java.security with parameters of type Set
    Constructor and Description
    `PrivateKeyEntry(PrivateKey privateKey, Certificate[] chain, Set<KeyStore.Entry.Attribute> attributes)` Constructs a `PrivateKeyEntry` with a `PrivateKey` and corresponding certificate chain and associated entry attributes.
    `SecretKeyEntry(SecretKey secretKey, Set<KeyStore.Entry.Attribute> attributes)` Constructs a `SecretKeyEntry` with a `SecretKey` and associated entry attributes.
    `TrustedCertificateEntry(Certificate trustedCert, Set<KeyStore.Entry.Attribute> attributes)` Constructs a `TrustedCertificateEntry` with a trusted `Certificate` and associated entry attributes.

  - ### Uses of Set in java.security.cert

    Methods in java.security.cert that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<String>` | X509Extension.`getCriticalExtensionOIDs()` Gets a Set of the OID strings for the extension(s) marked CRITICAL in the certificate/CRL managed by the object implementing this interface.
    `Set<String>` | PolicyNode.`getExpectedPolicies()` Returns the set of expected policies that would satisfy this node's valid policy in the next certificate to be processed.
    `Set<String>` | X509CertSelector.`getExtendedKeyUsage()` Returns the extendedKeyUsage criterion.
    `Set<String>` | PKIXParameters.`getInitialPolicies()` Returns an immutable `Set` of initial policy identifiers (OID strings), indicating that any one of these policies would be acceptable to the certificate user for the purposes of certification path processing.
    `Set<String>` | X509Extension.`getNonCriticalExtensionOIDs()` Gets a Set of the OID strings for the extension(s) marked NON-CRITICAL in the certificate/CRL managed by the object implementing this interface.
    `Set<PKIXRevocationChecker.Option>` | PKIXRevocationChecker.`getOptions()` Gets the revocation options.
    `Set<String>` | X509CertSelector.`getPolicy()` Returns the policy criterion.
    `Set<? extends PolicyQualifierInfo>` | PolicyNode.`getPolicyQualifiers()` Returns the set of policy qualifiers associated with the valid policy represented by this node.
    `abstract Set<? extends X509CRLEntry>` | X509CRL.`getRevokedCertificates()` Gets all the entries from this CRL.
    `abstract Set<String>` | PKIXCertPathChecker.`getSupportedExtensions()` Returns an immutable `Set` of X.509 certificate extensions that this `PKIXCertPathChecker` supports (i.e.
    `Set<TrustAnchor>` | PKIXParameters.`getTrustAnchors()` Returns an immutable `Set` of the most-trusted CAs.

    Methods in java.security.cert with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `void` | X509CertSelector.`setExtendedKeyUsage(Set<String> keyPurposeSet)` Sets the extendedKeyUsage criterion.
    `void` | PKIXParameters.`setInitialPolicies(Set<String> initialPolicies)` Sets the `Set` of initial policy identifiers (OID strings), indicating that any one of these policies would be acceptable to the certificate user for the purposes of certification path processing.
    `void` | PKIXRevocationChecker.`setOptions(Set<PKIXRevocationChecker.Option> options)` Sets the revocation options.
    `void` | X509CertSelector.`setPolicy(Set<String> certPolicySet)` Sets the policy constraint.
    `void` | PKIXParameters.`setTrustAnchors(Set<TrustAnchor> trustAnchors)` Sets the `Set` of most-trusted CAs.

    Constructors in java.security.cert with parameters of type Set
    Constructor and Description
    `PKIXBuilderParameters(Set<TrustAnchor> trustAnchors, CertSelector targetConstraints)` Creates an instance of `PKIXBuilderParameters` with the specified `Set` of most-trusted CAs.
    `PKIXParameters(Set<TrustAnchor> trustAnchors)` Creates an instance of `PKIXParameters` with the specified `Set` of most-trusted CAs.

  - ### Uses of Set in java.text

    Methods in java.text that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<AttributedCharacterIterator.Attribute>` | AttributedCharacterIterator.`getAllAttributeKeys()` Returns the keys of all attributes defined on the iterator's text range.

    Methods in java.text with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `int` | AttributedCharacterIterator.`getRunLimit(Set<? extends AttributedCharacterIterator.Attribute> attributes)` Returns the index of the first character following the run with respect to the given `attributes` containing the current character.
    `int` | AttributedCharacterIterator.`getRunStart(Set<? extends AttributedCharacterIterator.Attribute> attributes)` Returns the index of the first character of the run with respect to the given `attributes` containing the current character.

  - ### Uses of Set in java.time

    Methods in java.time that return Set
    Modifier and Type | Method and Description
    --- | ---
    `static Set<String>` | ZoneId.`getAvailableZoneIds()` Gets the set of available zone IDs.

  - ### Uses of Set in java.time.chrono

    Methods in java.time.chrono that return Set
    Modifier and Type | Method and Description
    --- | ---
    `static Set<Chronology>` | Chronology.`getAvailableChronologies()` Returns the available chronologies.

  - ### Uses of Set in java.time.format

    Methods in java.time.format that return Set
    Modifier and Type | Method and Description
    --- | ---
    `static Set<Locale>` | DecimalStyle.`getAvailableLocales()` Lists all the locales that are supported.
    `Set<TemporalField>` | DateTimeFormatter.`getResolverFields()` Gets the resolver fields to use during parsing.

    Methods in java.time.format with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `DateTimeFormatterBuilder` | DateTimeFormatterBuilder.`appendZoneText(TextStyle textStyle, Set<ZoneId> preferredZones)` Appends the time-zone name, such as 'British Summer Time', to the formatter.
    `DateTimeFormatter` | DateTimeFormatter.`withResolverFields(Set<TemporalField> resolverFields)` Returns a copy of this formatter with a new set of resolver fields.

  - ### Uses of Set in java.time.zone

    Methods in java.time.zone that return Set
    Modifier and Type | Method and Description
    --- | ---
    `static Set<String>` | ZoneRulesProvider.`getAvailableZoneIds()` Gets the set of available zone IDs.
    `protected abstract Set<String>` | ZoneRulesProvider.`provideZoneIds()` SPI method to get the available zone IDs.

  - ### Uses of Set in java.util

    Subinterfaces of Set in java.util
    Modifier and Type | Interface and Description
    --- | ---
    `interface` | `NavigableSet<E>` A `SortedSet` extended with navigation methods reporting closest matches for given search targets.
    `interface` | `SortedSet<E>` A `Set` that further provides a total ordering on its elements.

    Classes in java.util that implement Set
    Modifier and Type | Class and Description
    --- | ---
    `class` | `AbstractSet<E>` This class provides a skeletal implementation of the `Set` interface to minimize the effort required to implement this interface.
    `class` | `EnumSet<E extends Enum<E>>` A specialized `Set` implementation for use with enum types.
    `class` | `HashSet<E>` This class implements the `Set` interface, backed by a hash table (actually a `HashMap` instance).
    `class` | `LinkedHashSet<E>` Hash table and linked list implementation of the `Set` interface, with predictable iteration order.
    `class` | `TreeSet<E>` A `NavigableSet` implementation based on a `TreeMap`.

    Fields in java.util declared as Set
    Modifier and Type | Field and Description
    --- | ---
    `static Set` | Collections.`EMPTY_SET` The empty set (immutable).

    Methods in java.util that return Set
    Modifier and Type | Method and Description
    --- | ---
    `static <E> Set<E>` | Collections.`checkedSet(Set<E> s, Class<E> type)` Returns a dynamically typesafe view of the specified set.
    `static <T> Set<T>` | Collections.`emptySet()` Returns an empty set (immutable).
    `Set<Map.Entry<K,V>>` | EnumMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<Map.Entry<K,V>>` | LinkedHashMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `abstract Set<Map.Entry<K,V>>` | AbstractMap.`entrySet()`
    `Set<Map.Entry<K,V>>` | WeakHashMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<Map.Entry<K,V>>` | Hashtable.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<Map.Entry<K,V>>` | SortedMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<Map.Entry<K,V>>` | HashMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<Map.Entry<K,V>>` | TreeMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<Map.Entry<K,V>>` | Map.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<Map.Entry<K,V>>` | IdentityHashMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `static Set<String>` | Calendar.`getAvailableCalendarTypes()` Returns an unmodifiable `Set` containing all calendar types supported by `Calendar` in the runtime environment.
    `static Set<Currency>` | Currency.`getAvailableCurrencies()` Gets the set of available currencies.
    `Set<Character>` | Locale.`getExtensionKeys()` Returns the set of extension keys associated with this locale, or the empty set if it has no extensions.
    `Set<String>` | Locale.`getUnicodeLocaleAttributes()` Returns the set of unicode locale attributes associated with this locale, or the empty set if it has no attributes.
    `Set<String>` | Locale.`getUnicodeLocaleKeys()` Returns the set of Unicode locale keys defined by this locale, or the empty set if this locale has none.
    `protected Set<String>` | ListResourceBundle.`handleKeySet()` Returns a `Set` of the keys contained only in this `ResourceBundle`.
    `protected Set<String>` | PropertyResourceBundle.`handleKeySet()` Returns a `Set` of the keys contained only in this `ResourceBundle`.
    `protected Set<String>` | ResourceBundle.`handleKeySet()` Returns a `Set` of the keys contained only in this `ResourceBundle`.
    `Set<K>` | EnumMap.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<K>` | LinkedHashMap.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<K>` | AbstractMap.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<K>` | WeakHashMap.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<K>` | Hashtable.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<K>` | SortedMap.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<K>` | HashMap.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<String>` | ResourceBundle.`keySet()` Returns a `Set` of all keys contained in this `ResourceBundle` and its parent bundles.
    `Set<K>` | TreeMap.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<K>` | Map.`keySet()` Returns a `Set` view of the keys contained in this map.
    `Set<K>` | IdentityHashMap.`keySet()` Returns an identity-based set view of the keys contained in this map.
    `static <E> Set<E>` | Collections.`newSetFromMap(Map<E,Boolean> map)` Returns a set backed by the specified map.
    `static <T> Set<T>` | Collections.`singleton(T o)` Returns an immutable set containing only the specified object.
    `Set<String>` | Properties.`stringPropertyNames()` Returns a set of keys in this property list where the key and its corresponding value are strings, including distinct keys in the default property list if a key of the same name has not already been found from the main properties list.
    `static <T> Set<T>` | Collections.`synchronizedSet(Set<T> s)` Returns a synchronized (thread-safe) set backed by the specified set.
    `static <T> Set<T>` | Collections.`unmodifiableSet(Set<? extends T> s)` Returns an unmodifiable view of the specified set.

    Methods in java.util with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `static <E> Set<E>` | Collections.`checkedSet(Set<E> s, Class<E> type)` Returns a dynamically typesafe view of the specified set.
    `static <T> Set<T>` | Collections.`synchronizedSet(Set<T> s)` Returns a synchronized (thread-safe) set backed by the specified set.
    `static <T> Set<T>` | Collections.`unmodifiableSet(Set<? extends T> s)` Returns an unmodifiable view of the specified set.

  - ### Uses of Set in java.util.concurrent

    Classes in java.util.concurrent that implement Set
    Modifier and Type | Class and Description
    --- | ---
    `static class` | `ConcurrentHashMap.KeySetView<K,V>` A view of a ConcurrentHashMap as a `Set` of keys, in which additions may optionally be enabled by mapping to a common value.
    `class` | `ConcurrentSkipListSet<E>` A scalable concurrent `NavigableSet` implementation based on a `ConcurrentSkipListMap`.
    `class` | `CopyOnWriteArraySet<E>` A `Set` that uses an internal `CopyOnWriteArrayList` for all of its operations.

    Methods in java.util.concurrent that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Map.Entry<K,V>>` | ConcurrentSkipListMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<Map.Entry<K,V>>` | ConcurrentHashMap.`entrySet()` Returns a `Set` view of the mappings contained in this map.

  - ### Uses of Set in java.util.jar

    Methods in java.util.jar that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Map.Entry<Object,Object>>` | Attributes.`entrySet()` Returns a Collection view of the attribute name-value mappings contained in this Map.
    `Set<Object>` | Attributes.`keySet()` Returns a Set view of the attribute names (keys) contained in this Map.

  - ### Uses of Set in java.util.stream

    Methods in java.util.stream that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Collector.Characteristics>` | Collector.`characteristics()` Returns a `Set` of `Collector.Characteristics` indicating the characteristics of this Collector.

    Methods in java.util.stream that return types with arguments of type Set
    Modifier and Type | Method and Description
    --- | ---
    `static <T> Collector<T,?,Set<T>>` | Collectors.`toSet()` Returns a `Collector` that accumulates the input elements into a new `Set`.

  - ### Uses of Set in javax.annotation.processing

    Methods in javax.annotation.processing that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<? extends Element>` | RoundEnvironment.`getElementsAnnotatedWith(Class<? extends Annotation> a)` Returns the elements annotated with the given annotation type.
    `Set<? extends Element>` | RoundEnvironment.`getElementsAnnotatedWith(TypeElement a)` Returns the elements annotated with the given annotation type.
    `Set<? extends Element>` | RoundEnvironment.`getRootElements()` Returns the root elements for annotation processing generated by the prior round.
    `Set<String>` | AbstractProcessor.`getSupportedAnnotationTypes()` If the processor class is annotated with `SupportedAnnotationTypes`, return an unmodifiable set with the same set of strings as the annotation.
    `Set<String>` | Processor.`getSupportedAnnotationTypes()` Returns the names of the annotation types supported by this processor.
    `Set<String>` | AbstractProcessor.`getSupportedOptions()` If the processor class is annotated with `SupportedOptions`, return an unmodifiable set with the same set of strings as the annotation.
    `Set<String>` | Processor.`getSupportedOptions()` Returns the options recognized by this processor.

    Methods in javax.annotation.processing with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `abstract boolean` | AbstractProcessor.`process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv)` Processes a set of annotation types on type elements originating from the prior round and returns whether or not these annotation types are claimed by this processor.
    `boolean` | Processor.`process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv)` Processes a set of annotation types on type elements originating from the prior round and returns whether or not these annotation types are claimed by this processor.

  - ### Uses of Set in javax.imageio

    Methods in javax.imageio with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `IIOMetadata` | ImageReader.`getImageMetadata(int imageIndex, String formatName, Set<String> nodeNames)` Returns an `IIOMetadata` object representing the metadata associated with the given image, or `null` if the reader does not support reading metadata or none is available.
    `IIOMetadata` | ImageReader.`getStreamMetadata(String formatName, Set<String> nodeNames)` Returns an `IIOMetadata` object representing the metadata associated with the input source as a whole (i.e., not associated with any particular image).

  - ### Uses of Set in javax.lang.model.element

    Methods in javax.lang.model.element that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Modifier>` | Element.`getModifiers()` Returns the modifiers of this element, excluding annotations.

  - ### Uses of Set in javax.lang.model.util

    Methods in javax.lang.model.util that return Set
    Modifier and Type | Method and Description
    --- | ---
    `static Set<ExecutableElement>` | ElementFilter.`constructorsIn(Set<? extends Element> elements)` Returns a set of constructors in `elements`.
    `static Set<VariableElement>` | ElementFilter.`fieldsIn(Set<? extends Element> elements)` Returns a set of fields in `elements`.
    `static Set<ExecutableElement>` | ElementFilter.`methodsIn(Set<? extends Element> elements)` Returns a set of methods in `elements`.
    `static Set<PackageElement>` | ElementFilter.`packagesIn(Set<? extends Element> elements)` Returns a set of packages in `elements`.
    `static Set<TypeElement>` | ElementFilter.`typesIn(Set<? extends Element> elements)` Returns a set of types in `elements`.

    Methods in javax.lang.model.util with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `static Set<ExecutableElement>` | ElementFilter.`constructorsIn(Set<? extends Element> elements)` Returns a set of constructors in `elements`.
    `static Set<VariableElement>` | ElementFilter.`fieldsIn(Set<? extends Element> elements)` Returns a set of fields in `elements`.
    `static Set<ExecutableElement>` | ElementFilter.`methodsIn(Set<? extends Element> elements)` Returns a set of methods in `elements`.
    `static Set<PackageElement>` | ElementFilter.`packagesIn(Set<? extends Element> elements)` Returns a set of packages in `elements`.
    `static Set<TypeElement>` | ElementFilter.`typesIn(Set<? extends Element> elements)` Returns a set of types in `elements`.

  - ### Uses of Set in javax.management

    Methods in javax.management that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<ObjectInstance>` | MBeanServer.`queryMBeans(ObjectName name, QueryExp query)` Gets MBeans controlled by the MBean server.
    `Set<ObjectInstance>` | MBeanServerConnection.`queryMBeans(ObjectName name, QueryExp query)` Gets MBeans controlled by the MBean server.
    `Set<ObjectName>` | MBeanServer.`queryNames(ObjectName name, QueryExp query)` Gets the names of MBeans controlled by the MBean server.
    `Set<ObjectName>` | MBeanServerConnection.`queryNames(ObjectName name, QueryExp query)` Gets the names of MBeans controlled by the MBean server.

  - ### Uses of Set in javax.management.loading

    Methods in javax.management.loading that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Object>` | MLetMBean.`getMBeansFromURL(String url)` Loads a text file containing MLET tags that define the MBeans to be added to the MBean server.
    `Set<Object>` | MLet.`getMBeansFromURL(String url)` Loads a text file containing MLET tags that define the MBeans to be added to the MBean server.
    `Set<Object>` | MLetMBean.`getMBeansFromURL(URL url)` Loads a text file containing MLET tags that define the MBeans to be added to the MBean server.
    `Set<Object>` | MLet.`getMBeansFromURL(URL url)` Loads a text file containing MLET tags that define the MBeans to be added to the MBean server.

  - ### Uses of Set in javax.management.openmbean

    Methods in javax.management.openmbean that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Map.Entry<Object,Object>>` | TabularDataSupport.`entrySet()` Returns a collection view of the index to row mappings contained in this `TabularDataSupport` instance.
    `Set<?>` | OpenMBeanParameterInfo.`getLegalValues()` Returns the set of legal values for this parameter, if it has one, or `null` otherwise.
    `Set<?>` | OpenMBeanParameterInfoSupport.`getLegalValues()` Returns an unmodifiable Set of legal values for the parameter described by this `OpenMBeanParameterInfoSupport` instance, if specified, or `null` otherwise.
    `Set<?>` | OpenMBeanAttributeInfoSupport.`getLegalValues()` Returns an unmodifiable Set of legal values for the attribute described by this `OpenMBeanAttributeInfoSupport` instance, if specified, or `null` otherwise.
    `Set<String>` | CompositeType.`keySet()` Returns an unmodifiable Set view of all the item names defined by this `CompositeType` instance.
    `Set<?>` | TabularData.`keySet()` Returns a set view of the keys (ie the index values) of the `CompositeData` values (ie the rows) contained in this `TabularData` instance.
    `Set<Object>` | TabularDataSupport.`keySet()` Returns a set view of the keys contained in the underlying map of this `TabularDataSupport` instance used to index the rows.

  - ### Uses of Set in javax.management.remote.rmi

    Methods in javax.management.remote.rmi that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<ObjectInstance>` | RMIConnection.`queryMBeans(ObjectName name, MarshalledObject query, Subject delegationSubject)` Handles the method `MBeanServerConnection.queryMBeans(ObjectName, QueryExp)`.
    `Set` | RMIConnectionImpl_Stub.`queryMBeans(ObjectName $param_ObjectName_1, MarshalledObject $param_MarshalledObject_2, Subject $param_Subject_3)`
    `Set<ObjectInstance>` | RMIConnectionImpl.`queryMBeans(ObjectName name, MarshalledObject query, Subject delegationSubject)`
    `Set<ObjectName>` | RMIConnection.`queryNames(ObjectName name, MarshalledObject query, Subject delegationSubject)` Handles the method `MBeanServerConnection.queryNames(ObjectName, QueryExp)`.
    `Set` | RMIConnectionImpl_Stub.`queryNames(ObjectName $param_ObjectName_1, MarshalledObject $param_MarshalledObject_2, Subject $param_Subject_3)`
    `Set<ObjectName>` | RMIConnectionImpl.`queryNames(ObjectName name, MarshalledObject query, Subject delegationSubject)`

  - ### Uses of Set in javax.print.attribute.standard

    Classes in javax.print.attribute.standard that implement Set
    Modifier and Type | Class and Description
    --- | ---
    `class` | `JobStateReasons` Class JobStateReasons is a printing attribute class, a set of enumeration values, that provides additional information about the job's current state, i.e., information that augments the value of the job's `JobState` attribute.

    Methods in javax.print.attribute.standard that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<PrinterStateReason>` | PrinterStateReasons.`printerStateReasonSet(Severity severity)` Obtain an unmodifiable set view of the individual printer state reason attributes at the given severity level in this PrinterStateReasons attribute.

  - ### Uses of Set in javax.script

    Methods in javax.script that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Map.Entry<String,Object>>` | SimpleBindings.`entrySet()` Returns a `Set` view of the mappings contained in this map.
    `Set<String>` | SimpleBindings.`keySet()` Returns a `Set` view of the keys contained in this map.

  - ### Uses of Set in javax.security.auth

    Methods in javax.security.auth that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<Principal>` | Subject.`getPrincipals()` Return the `Set` of Principals associated with this `Subject`.
    `<T extends Principal> Set<T>` | Subject.`getPrincipals(Class<T> c)` Return a `Set` of Principals associated with this `Subject` that are instances or subclasses of the specified `Class`.
    `Set<Object>` | Subject.`getPrivateCredentials()` Return the `Set` of private credentials held by this `Subject`.
    `<T> Set<T>` | Subject.`getPrivateCredentials(Class<T> c)` Return a `Set` of private credentials associated with this `Subject` that are instances or subclasses of the specified `Class`.
    `Set<Object>` | Subject.`getPublicCredentials()` Return the `Set` of public credentials held by this `Subject`.
    `<T> Set<T>` | Subject.`getPublicCredentials(Class<T> c)` Return a `Set` of public credentials associated with this `Subject` that are instances or subclasses of the specified `Class`.

    Constructors in javax.security.auth with parameters of type Set
    Constructor and Description
    `Subject(boolean readOnly, Set<? extends Principal> principals, Set<?> pubCredentials, Set<?> privCredentials)` Create an instance of a `Subject` with Principals and credentials.
    `Subject(boolean readOnly, Set<? extends Principal> principals, Set<?> pubCredentials, Set<?> privCredentials)` Create an instance of a `Subject` with Principals and credentials.
    `Subject(boolean readOnly, Set<? extends Principal> principals, Set<?> pubCredentials, Set<?> privCredentials)` Create an instance of a `Subject` with Principals and credentials.

  - ### Uses of Set in javax.swing

    Methods in javax.swing with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `void` | JComponent.`setFocusTraversalKeys(int id, Set<? extends AWTKeyStroke> keystrokes)` Sets the focus traversal keys for a given traversal operation for this Component.

  - ### Uses of Set in javax.tools

    Methods in javax.tools that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<SourceVersion>` | Tool.`getSourceVersions()` Gets the source versions of the Java™ programming language supported by this tool.

    Methods in javax.tools with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `Iterable<JavaFileObject>` | JavaFileManager.`list(JavaFileManager.Location location, String packageName, Set<JavaFileObject.Kind> kinds, boolean recurse)` Lists all file objects matching the given criteria in the given location.
    `Iterable<JavaFileObject>` | ForwardingJavaFileManager.`list(JavaFileManager.Location location, String packageName, Set<JavaFileObject.Kind> kinds, boolean recurse)`

  - ### Uses of Set in javax.xml.ws

    Methods in javax.xml.ws that return Set
    Modifier and Type | Method and Description
    --- | ---
    `abstract Set<Endpoint>` | EndpointContext.`getEndpoints()` This gives list of endpoints in an application.

  - ### Uses of Set in javax.xml.ws.handler.soap

    Methods in javax.xml.ws.handler.soap that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<QName>` | SOAPHandler.`getHeaders()` Gets the header blocks that can be processed by this Handler instance.
    `Set<String>` | SOAPMessageContext.`getRoles()` Gets the SOAP actor roles associated with an execution of the handler chain.

  - ### Uses of Set in javax.xml.ws.soap

    Methods in javax.xml.ws.soap that return Set
    Modifier and Type | Method and Description
    --- | ---
    `Set<String>` | SOAPBinding.`getRoles()` Gets the roles played by the SOAP binding instance.

    Methods in javax.xml.ws.soap with parameters of type Set
    Modifier and Type | Method and Description
    --- | ---
    `void` | SOAPBinding.`setRoles(Set<String> roles)` Sets the roles played by the SOAP binding instance.

  - ### Uses of Set in javax.xml.ws.spi.http

    Methods in javax.xml.ws.spi.http that return Set
    Modifier and Type | Method and Description
    --- | ---
    `abstract Set<String>` | HttpContext.`getAttributeNames()` Returns all attribute names for container's configuration and other data that can be used by jax-ws runtime.
    `abstract Set<String>` | HttpExchange.`getAttributeNames()` Gives all the attribute names that are associated with this `HttpExchange`.

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