# Uses of Package
java.util

Packages that use java.util
Package
Description
com.sun.java.accessibility.util
Provides a collection of interfaces and classes that compose the Java Accessibility Utilities.
com.sun.jdi
This is the core package of the Java Debug Interface (JDI), it defines mirrors for values, types, and the target VirtualMachine itself - as well bootstrapping facilities.
com.sun.jdi.connect
This package defines connections between the virtual machine using the JDI and the target virtual machine.
com.sun.jdi.event
This package defines JDI events and event processing.
com.sun.jdi.request
This package is used to request that a JDI event be sent under specified conditions.
com.sun.management
This package contains JDK extensions to the standard implementation of the `java.lang.management` API and also defines the management interface for some other components of the platform.
com.sun.net.httpserver
Provides a simple high-level Http server API, which can be used to build embedded HTTP servers.
com.sun.nio.sctp
A Java API for Stream Control Transport Protocol.
com.sun.security.auth.module
Provides implementations of `LoginModule`.
com.sun.source.doctree
Provides interfaces to represent documentation comments as abstract syntax trees (AST).
com.sun.source.tree
Provides interfaces to represent source code as abstract syntax trees (AST).
com.sun.source.util
Provides utilities for operations on abstract syntax trees (AST).
com.sun.tools.attach
Provides the API to attach to a Java virtual machine.
com.sun.tools.attach.spi
Only developers who are defining new attach providers should need to make direct use of this package.
com.sun.tools.jconsole
This package contains the JConsole API.
java.awt
Contains all of the classes for creating user interfaces and for painting graphics and images.
java.awt.datatransfer
Provides interfaces and classes for transferring data between and within applications.
java.awt.desktop
Provides interfaces and classes for interaction with various desktop capabilities.
java.awt.dnd
Drag and Drop is a direct manipulation gesture found in many Graphical User Interface systems that provides a mechanism to transfer information between two entities logically associated with presentation elements in the GUI.
java.awt.event
Provides interfaces and classes for dealing with different types of events fired by AWT components.
java.awt.font
Provides classes and interface relating to fonts.
java.awt.im
Provides classes and interfaces for the input method framework.
java.awt.im.spi
Provides interfaces that enable the development of input methods that can be used with any Java runtime environment.
java.awt.image
Provides classes for creating and modifying images.
java.awt.image.renderable
Provides classes and interfaces for producing rendering-independent images.
java.beans
Contains classes related to developing beans -- components based on the JavaBeans architecture.
java.beans.beancontext
Provides classes and interfaces relating to bean context.
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.lang.classfile
Provides classfile parsing, generation, and transformation library.
java.lang.classfile.attribute
Provides interfaces describing `class` file attributes for the `java.lang.classfile` library.
java.lang.classfile.constantpool
Provides interfaces describing constant pool entries for the `java.lang.classfile` library.
java.lang.classfile.instruction
Provides interfaces describing code instructions for the `java.lang.classfile` library.
java.lang.constant
Classes and interfaces to represent nominal descriptors for run-time entities such as classes or method handles, and classfile entities such as constant pool entries or `invokedynamic` call sites.
java.lang.foreign
Provides low-level access to memory and functions outside the Java runtime.
java.lang.instrument
Provides services that allow Java programming language agents to instrument programs running on the Java Virtual Machine (JVM).
java.lang.invoke
The `java.lang.invoke` package provides low-level primitives for interacting with the Java Virtual Machine.
java.lang.management
Provides the management interfaces for monitoring and management of the Java virtual machine and other components in the Java runtime.
java.lang.module
Classes to support module descriptors and creating configurations of modules by means of resolution and service binding.
java.lang.reflect
Provides classes and interfaces for obtaining reflective information about classes and objects.
java.math
Provides classes for performing arbitrary-precision integer arithmetic (`BigInteger`) and arbitrary-precision decimal arithmetic (`BigDecimal`).
java.net
Provides the classes for implementing networking applications.
java.net.http
HTTP Client and WebSocket APIs
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.charset.spi
Service-provider classes for the `java.nio.charset` package.
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.security.interfaces
Provides interfaces for generating RSA (Rivest, Shamir and Adleman AsymmetricCipher algorithm) keys as defined in the RSA Laboratory Technical Note PKCS#1, and DSA (Digital Signature Algorithm) keys as defined in NIST's FIPS-186.
java.security.spec
Provides classes and interfaces for key specifications and algorithm parameter specifications.
java.sql
Provides the API for accessing and processing data stored in a data source (usually a relational database) using the Java programming language.
java.text
Provides classes and interfaces for handling text, dates, numbers, and messages in a manner independent of natural languages.
java.text.spi
Service provider classes for the classes in the java.text package.
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.temporal
Access to date and time using fields and units, and date time adjusters.
java.time.zone
Support for time-zones and their rules.
java.util
Contains the collections framework, some internationalization support classes, a service loader, properties, random number generation, string parsing and scanning classes, base64 encoding and decoding, a bit array, and several miscellaneous utility classes.
java.util.concurrent
Utility classes commonly useful in concurrent programming.
java.util.concurrent.locks
Interfaces and classes providing a framework for locking and waiting for conditions that is distinct from built-in synchronization and monitors.
java.util.function
Functional interfaces provide target types for lambda expressions and method references.
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.logging
Provides the classes and interfaces of the Java 2 platform's core logging facilities.
java.util.prefs
This package allows applications to store and retrieve user and system preference and configuration data.
java.util.regex
Classes for matching character sequences against patterns specified by regular expressions.
java.util.spi
Service provider classes for the classes in the java.util package.
java.util.stream
Classes to support functional-style operations on streams of elements, such as map-reduce transformations on collections.
java.util.zip
Provides classes for reading and writing the standard ZIP and GZIP file formats.
javax.accessibility
Defines a contract between user-interface components and an assistive technology that provides access to those components.
javax.annotation.processing
Facilities for declaring annotation processors and for allowing annotation processors to communicate with an annotation processing tool environment.
javax.crypto.spec
Provides classes and interfaces for key specifications and algorithm parameter specifications.
javax.imageio
The main package of the Java Image I/O API.
javax.imageio.event
A package of the Java Image I/O API dealing with synchronous notification of events during the reading and writing of images.
javax.imageio.metadata
A package of the Java Image I/O API dealing with reading and writing metadata.
javax.imageio.plugins.bmp
Package containing the public classes used by the built-in BMP plug-in.
javax.imageio.plugins.jpeg
Classes supporting the built-in JPEG plug-in.
javax.imageio.plugins.tiff
Public classes used by the built-in TIFF plug-ins.
javax.imageio.spi
A package of the Java Image I/O API containing the plug-in interfaces for readers, writers, transcoders, and streams, and a runtime registry.
javax.lang.model
Types and hierarchies of packages comprising a Java language model, a reflective API that models the declarations and types of the Java programming language.
javax.lang.model.element
Interfaces used to model elements of the Java programming language.
javax.lang.model.type
Interfaces used to model Java programming language types.
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.monitor
Provides the definition of the monitor classes.
javax.management.openmbean
Provides the open data types and Open MBean descriptor classes.
javax.management.relation
Provides the definition of the Relation Service.
javax.management.remote
Interfaces for remote access to JMX MBean servers.
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.management.timer
Provides the definition of the Timer MBean.
javax.naming
Provides the classes and interfaces for accessing naming services.
javax.naming.directory
Extends the `javax.naming` package to provide functionality for accessing directory services.
javax.naming.event
Provides support for event notification when accessing naming and directory services.
javax.naming.ldap
Provides support for LDAPv3 extended operations and controls.
javax.naming.ldap.spi
Provides the Service Provider Interface for DNS lookups when performing LDAP operations.
javax.naming.spi
Provides the means for dynamically plugging in support for accessing naming and directory services through the `javax.naming` and related packages.
javax.net.ssl
Provides classes for the secure socket package.
javax.print.attribute
Provides classes and interfaces that describe the types of Java Print Service attributes and how they can be collected into attribute sets.
javax.print.attribute.standard
Package `javax.print.attribute.standard` contains classes for specific printing attributes.
javax.print.event
Package `javax.print.event` contains event classes and listener interfaces.
javax.script
The scripting API consists of interfaces and classes that define Java 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.security.auth.callback
This package provides the classes necessary for services to interact with applications in order to retrieve information (authentication data including usernames or passwords, for example) or to display information (error and warning messages, for example).
javax.security.auth.kerberos
This package contains utility classes related to the Kerberos network authentication protocol.
javax.security.auth.login
This package provides a pluggable authentication framework.
javax.security.auth.spi
This package provides the interface to be used for implementing pluggable authentication modules.
javax.security.auth.x500
This package contains the classes that should be used to store X500 Principal and X500 Private Credentials in a Subject.
javax.security.cert
Provides classes for public key certificates.
javax.security.sasl
Contains class and interfaces for supporting SASL.
javax.smartcardio
Java™ Smart Card I/O API.
javax.sound.midi
Provides interfaces and classes for I/O, sequencing, and synthesis of MIDI (Musical Instrument Digital Interface) data.
javax.sound.sampled
Provides interfaces and classes for capture, processing, and playback of sampled audio data.
javax.sql
Provides the API for server side data source access and processing from the Java programming language.
javax.sql.rowset
Standard interfaces and base classes for JDBC `RowSet` implementations.
javax.sql.rowset.serial
Provides utility classes to allow serializable mappings between SQL types and data types in the Java programming language.
javax.sql.rowset.spi
The standard classes and interfaces that a third party vendor has to use in its implementation of a synchronization provider.
javax.swing
Provides a set of "lightweight" (all-Java language) components that, to the maximum degree possible, work the same on all platforms.
javax.swing.event
Provides for events fired by Swing components.
javax.swing.plaf.basic
Provides user interface objects built according to the Basic look and feel.
javax.swing.plaf.metal
Provides user interface objects built according to the Java look and feel (once codenamed Metal), which is the default look and feel.
javax.swing.plaf.multi
Provides user interface objects that combine two or more look and feels.
javax.swing.plaf.synth
Synth is a skinnable look and feel in which all painting is delegated.
javax.swing.table
Provides classes and interfaces for dealing with `javax.swing.JTable`.
javax.swing.text
Provides classes and interfaces that deal with editable and noneditable text components.
javax.swing.text.html
Provides the class `HTMLEditorKit` and supporting classes for creating HTML text editors.
javax.swing.text.html.parser
Provides the default HTML parser, along with support classes.
javax.swing.tree
Provides classes and interfaces for dealing with `javax.swing.JTree`.
javax.swing.undo
Allows developers to provide support for undo/redo in applications such as text editors.
javax.tools
Provides interfaces for tools which can be invoked from a program, for example, compilers.
javax.xml.crypto
Common classes for XML cryptography.
javax.xml.crypto.dom
DOM-specific classes for the `javax.xml.crypto` package.
javax.xml.crypto.dsig
Classes for generating and validating XML digital signatures.
javax.xml.crypto.dsig.keyinfo
Classes for parsing and processing `KeyInfo` elements and structures.
javax.xml.crypto.dsig.spec
Parameter classes for XML digital signatures.
javax.xml.datatype
Defines XML/Java Type Mappings.
javax.xml.namespace
Defines XML Namespace processing.
javax.xml.stream
Defines interfaces and classes for the Streaming API for XML (StAX).
javax.xml.stream.events
Defines event interfaces for the Streaming API for XML (StAX).
javax.xml.stream.util
Provides utility classes for the Streaming API for XML (StAX).
javax.xml.transform
Defines the generic APIs for processing transformation instructions, and performing a transformation from source to result.
javax.xml.xpath
Provides an object-model neutral API for the evaluation of XPath expressions and access to the evaluation environment.
jdk.dynalink
Contains interfaces and classes that are used to link an `invokedynamic` call site.
jdk.dynalink.beans
Contains the linker for ordinary Java objects.
jdk.dynalink.linker
Contains interfaces and classes needed by language runtimes to implement their own language-specific object models and type conversions.
jdk.dynalink.linker.support
Contains classes that make it more convenient for language runtimes to implement their own language-specific object models and type conversions by providing basic implementations of some classes as well as various utilities.
jdk.javadoc.doclet
The Doclet API provides an environment which, in conjunction with the Language Model API and Compiler Tree API, allows clients to inspect the source-level structures of programs and libraries, including API comments embedded in the source.
jdk.jfr
This package provides classes to create events and control Flight Recorder.
jdk.jfr.consumer
This package contains classes for consuming Flight Recorder data.
jdk.jshell
Provides interfaces for creating tools, such as a Read-Eval-Print Loop (REPL), which interactively evaluate "snippets" of Java programming language code.
jdk.jshell.execution
Provides implementation support for building JShell execution engines.
jdk.jshell.spi
Defines the Service Provider Interface for pluggable JShell execution engines.
jdk.jshell.tool
Provides a mechanism to launch an instance of a Java shell tool.
jdk.management.jfr
This package contains classes to control and monitor Flight Recorder over Java Management Extensions (JMX).
jdk.net
Platform specific socket options for the `java.net` and `java.nio.channels` socket classes.
org.xml.sax
Provides the interfaces for the Simple API for XML (SAX).
org.xml.sax.helpers
Provides helper classes, including support for bootstrapping SAX-based applications.

Classes in java.util used by com.sun.java.accessibility.util
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by com.sun.jdi
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Classes in java.util used by com.sun.jdi.connect
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Classes in java.util used by com.sun.jdi.event
Class
Description
Collection
The root interface in the collection hierarchy.
Iterator
An iterator over a collection.
Set
A collection that contains no duplicate elements.
Classes in java.util used by com.sun.jdi.request
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by com.sun.management
Class
Description
Collection
The root interface in the collection hierarchy.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Classes in java.util used by com.sun.net.httpserver
Class
Description
Collection
The root interface in the collection hierarchy.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Map.Entry
A map entry (key-value pair).
Set
A collection that contains no duplicate elements.
Classes in java.util used by com.sun.nio.sctp
Class
Description
Set
A collection that contains no duplicate elements.
Classes in java.util used by com.sun.security.auth.module
Class
Description
Map
An object that maps keys to values.
Classes in java.util used by com.sun.source.doctree
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by com.sun.source.tree
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Set
A collection that contains no duplicate elements.
Classes in java.util used by com.sun.source.util
Class
Description
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by com.sun.tools.attach
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Properties
The `Properties` class represents a persistent set of properties.
Classes in java.util used by com.sun.tools.attach.spi
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by com.sun.tools.jconsole
Class
Description
Map
An object that maps keys to values.
Classes in java.util used by java.awt
Class
Description
Collection
The root interface in the collection hierarchy.
EmptyStackException
Thrown by methods in the `Stack` class to indicate that the stack is empty.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Hashtable
This class implements a hash table, which maps keys to values.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Map.Entry
A map entry (key-value pair).
Properties
The `Properties` class represents a persistent set of properties.
ResourceBundle
Resource bundles contain locale-specific objects.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.awt.datatransfer
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Classes in java.util used by java.awt.desktop
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by java.awt.dnd
Class
Description
ArrayList
Resizable-array implementation of the `List` interface.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
TooManyListenersException
The `TooManyListenersException` Exception is used as part of the Java Event model to annotate and implement a unicast special case of a multicast Event Source.
Classes in java.util used by java.awt.event
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
EventListenerProxy
An abstract wrapper class for an `EventListener` class which associates a set of additional parameters with the listener.
EventObject
The root class from which all event state objects shall be derived.
Classes in java.util used by java.awt.font
Class
Description
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.awt.im
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Classes in java.util used by java.awt.im.spi
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by java.awt.image
Class
Description
Hashtable
This class implements a hash table, which maps keys to values.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by java.awt.image.renderable
Class
Description
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by java.beans
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
EventListenerProxy
An abstract wrapper class for an `EventListener` class which associates a set of additional parameters with the listener.
EventObject
The root class from which all event state objects shall be derived.
Classes in java.util used by java.beans.beancontext
Class
Description
ArrayList
Resizable-array implementation of the `List` interface.
Collection
The root interface in the collection hierarchy.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
HashMap
Hash table based implementation of the `Map` interface.
Iterator
An iterator over a collection.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
TooManyListenersException
The `TooManyListenersException` Exception is used as part of the Java Event model to annotate and implement a unicast special case of a multicast Event Source.
Classes in java.util used by java.io
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by java.lang
Class
Description
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
Properties
The `Properties` class represents a persistent set of properties.
ResourceBundle
Resource bundles contain locale-specific objects.
Set
A collection that contains no duplicate elements.
Spliterator
An object for traversing and partitioning elements of a source.
Classes in java.util used by java.lang.classfile
Class
Description
Collection
The root interface in the collection hierarchy.
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.lang.classfile.attribute
Class
Description
Collection
The root interface in the collection hierarchy.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Optional
A container object which may or may not contain a non-`null` value.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.lang.classfile.constantpool
Class
Description
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by java.lang.classfile.instruction
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Optional
A container object which may or may not contain a non-`null` value.
Classes in java.util used by java.lang.constant
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Optional
A container object which may or may not contain a non-`null` value.
Classes in java.util used by java.lang.foreign
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
Spliterator
An object for traversing and partitioning elements of a source.
Classes in java.util used by java.lang.instrument
Class
Description
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.lang.invoke
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Optional
A container object which may or may not contain a non-`null` value.
Classes in java.util used by java.lang.management
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.lang.module
Class
Description
Collection
The root interface in the collection hierarchy.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Optional
A container object which may or may not contain a non-`null` value.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.lang.reflect
Class
Description
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.math
Class
Description
Random
An instance of this class is used to generate a stream of pseudorandom numbers; its period is only 248.
Classes in java.util used by java.net
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.net.http
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
OptionalLong
A container object which may or may not contain a `long` value.
Classes in java.util used by java.nio.channels
Class
Description
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.nio.channels.spi
Class
Description
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.nio.charset
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Set
A collection that contains no duplicate elements.
SortedMap
A `Map` that further provides a total ordering on its keys.
Classes in java.util used by java.nio.charset.spi
Class
Description
Iterator
An iterator over a collection.
Classes in java.util used by java.nio.file
Class
Description
ConcurrentModificationException
This exception may be thrown by methods that have detected concurrent modification of an object when such modification is not permissible.
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.nio.file.attribute
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.nio.file.spi
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.security
Class
Description
Collection
The root interface in the collection hierarchy.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Dictionary
The `Dictionary` class is the abstract parent of any class, such as `Hashtable`, which maps keys to values.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Hashtable
This class implements a hash table, which maps keys to values.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Map.Entry
A map entry (key-value pair).
Properties
The `Properties` class represents a persistent set of properties.
Random
An instance of this class is used to generate a stream of pseudorandom numbers; its period is only 248.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.security.cert
Class
Description
Collection
The root interface in the collection hierarchy.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.security.interfaces
Class
Description
Optional
A container object which may or may not contain a non-`null` value.
Classes in java.util used by java.security.spec
Class
Description
Optional
A container object which may or may not contain a non-`null` value.
Classes in java.util used by java.sql
Class
Description
Calendar
The `Calendar` class is an abstract class that provides methods for converting between a specific instant in time and a set of `calendar fields` such as `YEAR`, `MONTH`, `DAY_OF_MONTH`, `HOUR`, and so on, and for manipulating the calendar fields, such as getting the date of the next week.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Iterator
An iterator over a collection.
Map
An object that maps keys to values.
Properties
The `Properties` class represents a persistent set of properties.
Classes in java.util used by java.text
Class
Description
Calendar
The `Calendar` class is an abstract class that provides methods for converting between a specific instant in time and a set of `calendar fields` such as `YEAR`, `MONTH`, `DAY_OF_MONTH`, `HOUR`, and so on, and for manipulating the calendar fields, such as getting the date of the next week.
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
Currency
Represents a currency.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
TimeZone
`TimeZone` represents a time zone offset, and also figures out daylight savings.
Classes in java.util used by java.text.spi
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by java.time
Class
Description
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.time.chrono
Class
Description
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.time.format
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.time.temporal
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Classes in java.util used by java.time.zone
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
NavigableMap
A `SortedMap` extended with navigation methods returning the closest matches for given search targets.
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.util
Class
Description
AbstractCollection
This class provides a skeletal implementation of the `Collection` interface, to minimize the effort required to implement this interface.
AbstractList
This class provides a skeletal implementation of the `List` interface to minimize the effort required to implement this interface backed by a "random access" data store (such as an array).
AbstractMap
This class provides a skeletal implementation of the `Map` interface, to minimize the effort required to implement this interface.
AbstractQueue
This class provides skeletal implementations of some `Queue` operations.
AbstractSequentialList
This class provides a skeletal implementation of the `List` interface to minimize the effort required to implement this interface backed by a "sequential access" data store (such as a linked list).
AbstractSet
This class provides a skeletal implementation of the `Set` interface to minimize the effort required to implement this interface.
ArrayDeque
Resizable-array implementation of the `Deque` interface.
ArrayList
Resizable-array implementation of the `List` interface.
Base64.Decoder
This class implements a decoder for decoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.
Base64.Encoder
This class implements an encoder for encoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.
BitSet
This class implements a vector of bits that grows as needed.
Calendar
The `Calendar` class is an abstract class that provides methods for converting between a specific instant in time and a set of `calendar fields` such as `YEAR`, `MONTH`, `DAY_OF_MONTH`, `HOUR`, and so on, and for manipulating the calendar fields, such as getting the date of the next week.
Calendar.Builder
`Calendar.Builder` is used for creating a `Calendar` from various date-time parameters.
Collection
The root interface in the collection hierarchy.
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
Currency
Represents a currency.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Deque
A linear collection that supports element insertion and removal at both ends.
Dictionary
The `Dictionary` class is the abstract parent of any class, such as `Hashtable`, which maps keys to values.
DoubleSummaryStatistics
A state object for collecting statistics such as count, min, max, sum, and average.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EnumMap
A specialized `Map` implementation for use with enum type keys.
EnumSet
A specialized `Set` implementation for use with enum types.
EventListener
A tagging interface that all event listener interfaces must extend.
Formatter
An interpreter for printf-style format strings.
Formatter.BigDecimalLayoutForm
Enum for `BigDecimal` formatting.
GregorianCalendar
`GregorianCalendar` is a concrete subclass of `Calendar` and provides the standard calendar system used by most of the world.
HashMap
Hash table based implementation of the `Map` interface.
HashSet
This class implements the `Set` interface, backed by a hash table (actually a `HashMap` instance).
Hashtable
This class implements a hash table, which maps keys to values.
HexFormat
`HexFormat` converts between bytes and chars and hex-encoded strings which may include additional formatting markup such as prefixes, suffixes, and delimiters.
IllegalFormatException
Unchecked exception thrown when a format string contains an illegal syntax or a format specifier that is incompatible with the given arguments.
IntSummaryStatistics
A state object for collecting statistics such as count, min, max, sum, and average.
InvalidPropertiesFormatException
Thrown to indicate that an operation could not complete because the input did not conform to the appropriate XML document type for a collection of properties, as per the `Properties` specification.
Iterator
An iterator over a collection.
LinkedHashMap
Hash table and linked list implementation of the `Map` interface, with well-defined encounter order.
LinkedHashSet
Hash table and linked list implementation of the `Set` interface, with well-defined encounter order.
LinkedList
Doubly-linked list implementation of the `List` and `Deque` interfaces.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
ListIterator
An iterator for lists that allows the programmer to traverse the list in either direction, modify the list during iteration, and obtain the iterator's current position in the list.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Locale.Builder
`Builder` is used to build instances of `Locale` from values configured by the setters.
Locale.Category
Enum for locale categories.
Locale.FilteringMode
This enum provides constants to select a filtering mode for locale matching.
Locale.IsoCountryCode
Enum for specifying the type defined in ISO 3166.
Locale.LanguageRange
This class expresses a Language Range defined in RFC 4647 Matching of Language Tags.
LongSummaryStatistics
A state object for collecting statistics such as count, min, max, sum, and average.
Map
An object that maps keys to values.
Map.Entry
A map entry (key-value pair).
MissingResourceException
Signals that a resource is missing.
NavigableMap
A `SortedMap` extended with navigation methods returning the closest matches for given search targets.
NavigableSet
A `SortedSet` extended with navigation methods reporting closest matches for given search targets.
NoSuchElementException
Thrown by various accessor methods to indicate that the element being requested does not exist.
Observable
Deprecated.
This class and the `Observer` interface have been deprecated.
Observer
Deprecated.
This interface has been deprecated.
Optional
A container object which may or may not contain a non-`null` value.
OptionalDouble
A container object which may or may not contain a `double` value.
OptionalInt
A container object which may or may not contain an `int` value.
OptionalLong
A container object which may or may not contain a `long` value.
PrimitiveIterator
A base type for primitive specializations of `Iterator`.
PrimitiveIterator.OfDouble
An Iterator specialized for `double` values.
PrimitiveIterator.OfInt
An Iterator specialized for `int` values.
PrimitiveIterator.OfLong
An Iterator specialized for `long` values.
PriorityQueue
An unbounded priority queue based on a priority heap.
Properties
The `Properties` class represents a persistent set of properties.
Queue
A collection designed for holding elements prior to processing.
Random
An instance of this class is used to generate a stream of pseudorandom numbers; its period is only 248.
RandomAccess
Marker interface used by `List` implementations to indicate that they support fast (generally constant time) random access.
ResourceBundle
Resource bundles contain locale-specific objects.
ResourceBundle.Control
`ResourceBundle.Control` defines a set of callback methods that are invoked by the `ResourceBundle.getBundle` factory methods during the bundle loading process.
Scanner
A simple text scanner which can parse primitive types and strings using regular expressions.
SequencedCollection
A collection that has a well-defined encounter order, that supports operations at both ends, and that is reversible.
SequencedMap
A Map that has a well-defined encounter order, that supports operations at both ends, and that is reversible.
SequencedSet
A collection that is both a `SequencedCollection` and a `Set`.
ServiceLoader
A facility to load implementations of a service.
ServiceLoader.Provider
Represents a service provider located by `ServiceLoader`.
Set
A collection that contains no duplicate elements.
SortedMap
A `Map` that further provides a total ordering on its keys.
SortedSet
A `Set` that further provides a total ordering on its elements.
Spliterator
An object for traversing and partitioning elements of a source.
Spliterator.OfDouble
A Spliterator specialized for `double` values.
Spliterator.OfInt
A Spliterator specialized for `int` values.
Spliterator.OfLong
A Spliterator specialized for `long` values.
Spliterator.OfPrimitive
A Spliterator specialized for primitive values.
SplittableRandom
A generator of uniform pseudorandom values (with period 264) applicable for use in (among other contexts) isolated parallel computations that may generate subtasks.
StringJoiner
`StringJoiner` is used to construct a sequence of characters separated by a delimiter and optionally starting with a supplied prefix and ending with a supplied suffix.
TimerTask
A task that can be scheduled for one-time or repeated execution by a `Timer`.
TimeZone
`TimeZone` represents a time zone offset, and also figures out daylight savings.
UUID
A class that represents an immutable universally unique identifier (UUID).
Vector
The `Vector` class implements a growable array of objects.
WeakHashMap
Hash table based implementation of the `Map` interface, with weak keys.
Classes in java.util used by java.util.concurrent
Class
Description
AbstractCollection
This class provides a skeletal implementation of the `Collection` interface, to minimize the effort required to implement this interface.
AbstractMap
This class provides a skeletal implementation of the `Map` interface, to minimize the effort required to implement this interface.
AbstractQueue
This class provides skeletal implementations of some `Queue` operations.
AbstractSet
This class provides a skeletal implementation of the `Set` interface to minimize the effort required to implement this interface.
Collection
The root interface in the collection hierarchy.
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
Deque
A linear collection that supports element insertion and removal at both ends.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
ListIterator
An iterator for lists that allows the programmer to traverse the list in either direction, modify the list during iteration, and obtain the iterator's current position in the list.
Map
An object that maps keys to values.
Map.Entry
A map entry (key-value pair).
NavigableMap
A `SortedMap` extended with navigation methods returning the closest matches for given search targets.
NavigableSet
A `SortedSet` extended with navigation methods reporting closest matches for given search targets.
Queue
A collection designed for holding elements prior to processing.
Random
An instance of this class is used to generate a stream of pseudorandom numbers; its period is only 248.
RandomAccess
Marker interface used by `List` implementations to indicate that they support fast (generally constant time) random access.
SequencedCollection
A collection that has a well-defined encounter order, that supports operations at both ends, and that is reversible.
SequencedMap
A Map that has a well-defined encounter order, that supports operations at both ends, and that is reversible.
SequencedSet
A collection that is both a `SequencedCollection` and a `Set`.
Set
A collection that contains no duplicate elements.
SortedMap
A `Map` that further provides a total ordering on its keys.
SortedSet
A `Set` that further provides a total ordering on its elements.
Spliterator
An object for traversing and partitioning elements of a source.
Classes in java.util used by java.util.concurrent.locks
Class
Description
Collection
The root interface in the collection hierarchy.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Classes in java.util used by java.util.function
Class
Description
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
Classes in java.util used by java.util.jar
Class
Description
Collection
The root interface in the collection hierarchy.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Map
An object that maps keys to values.
Map.Entry
A map entry (key-value pair).
Set
A collection that contains no duplicate elements.
Classes in java.util used by java.util.logging
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
ResourceBundle
Resource bundles contain locale-specific objects.
Classes in java.util used by java.util.prefs
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Classes in java.util used by java.util.regex
Class
Description
Map
An object that maps keys to values.
Classes in java.util used by java.util.spi
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
ResourceBundle
Resource bundles contain locale-specific objects.
ResourceBundle.Control
`ResourceBundle.Control` defines a set of callback methods that are invoked by the `ResourceBundle.getBundle` factory methods during the bundle loading process.
Classes in java.util used by java.util.stream
Class
Description
Collection
The root interface in the collection hierarchy.
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
DoubleSummaryStatistics
A state object for collecting statistics such as count, min, max, sum, and average.
IntSummaryStatistics
A state object for collecting statistics such as count, min, max, sum, and average.
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
LongSummaryStatistics
A state object for collecting statistics such as count, min, max, sum, and average.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
OptionalDouble
A container object which may or may not contain a `double` value.
OptionalInt
A container object which may or may not contain an `int` value.
OptionalLong
A container object which may or may not contain a `long` value.
Set
A collection that contains no duplicate elements.
Spliterator
An object for traversing and partitioning elements of a source.
Spliterator.OfDouble
A Spliterator specialized for `double` values.
Spliterator.OfInt
A Spliterator specialized for `int` values.
Spliterator.OfLong
A Spliterator specialized for `long` values.
Classes in java.util used by java.util.zip
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Classes in java.util used by javax.accessibility
Class
Description
ListResourceBundle
`ListResourceBundle` is an abstract subclass of `ResourceBundle` that manages resources for a locale in a convenient and easy to use list.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
ResourceBundle
Resource bundles contain locale-specific objects.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.annotation.processing
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.crypto.spec
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by javax.imageio
Class
Description
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.imageio.event
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
Classes in java.util used by javax.imageio.metadata
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by javax.imageio.plugins.bmp
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by javax.imageio.plugins.jpeg
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by javax.imageio.plugins.tiff
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
SortedSet
A `Set` that further provides a total ordering on its elements.
Classes in java.util used by javax.imageio.spi
Class
Description
Iterator
An iterator over a collection.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by javax.lang.model
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by javax.lang.model.element
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.lang.model.type
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by javax.lang.model.util
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.management
Class
Description
AbstractCollection
This class provides a skeletal implementation of the `Collection` interface, to minimize the effort required to implement this interface.
AbstractList
This class provides a skeletal implementation of the `List` interface to minimize the effort required to implement this interface backed by a "random access" data store (such as an array).
ArrayList
Resizable-array implementation of the `List` interface.
Collection
The root interface in the collection hierarchy.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Hashtable
This class implements a hash table, which maps keys to values.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
RandomAccess
Marker interface used by `List` implementations to indicate that they support fast (generally constant time) random access.
SequencedCollection
A collection that has a well-defined encounter order, that supports operations at both ends, and that is reversible.
Set
A collection that contains no duplicate elements.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.management.monitor
Class
Description
EventObject
The root class from which all event state objects shall be derived.
Classes in java.util used by javax.management.openmbean
Class
Description
Collection
The root interface in the collection hierarchy.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Map.Entry
A map entry (key-value pair).
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.management.relation
Class
Description
AbstractCollection
This class provides a skeletal implementation of the `Collection` interface, to minimize the effort required to implement this interface.
AbstractList
This class provides a skeletal implementation of the `List` interface to minimize the effort required to implement this interface backed by a "random access" data store (such as an array).
ArrayList
Resizable-array implementation of the `List` interface.
Collection
The root interface in the collection hierarchy.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
RandomAccess
Marker interface used by `List` implementations to indicate that they support fast (generally constant time) random access.
SequencedCollection
A collection that has a well-defined encounter order, that supports operations at both ends, and that is reversible.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.management.remote
Class
Description
EventObject
The root class from which all event state objects shall be derived.
Map
An object that maps keys to values.
Classes in java.util used by javax.management.remote.rmi
Class
Description
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.management.timer
Class
Description
Date
The class `Date` represents a specific instant in time, with millisecond precision.
EventObject
The root class from which all event state objects shall be derived.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.naming
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Hashtable
This class implements a hash table, which maps keys to values.
Properties
The `Properties` class represents a persistent set of properties.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.naming.directory
Class
Description
Hashtable
This class implements a hash table, which maps keys to values.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.naming.event
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Classes in java.util used by javax.naming.ldap
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Hashtable
This class implements a hash table, which maps keys to values.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by javax.naming.ldap.spi
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
Classes in java.util used by javax.naming.spi
Class
Description
Hashtable
This class implements a hash table, which maps keys to values.
Classes in java.util used by javax.net.ssl
Class
Description
Collection
The root interface in the collection hierarchy.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Optional
A container object which may or may not contain a non-`null` value.
Classes in java.util used by javax.print.attribute
Class
Description
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by javax.print.attribute.standard
Class
Description
AbstractCollection
This class provides a skeletal implementation of the `Collection` interface, to minimize the effort required to implement this interface.
AbstractMap
This class provides a skeletal implementation of the `Map` interface, to minimize the effort required to implement this interface.
AbstractSet
This class provides a skeletal implementation of the `Set` interface to minimize the effort required to implement this interface.
Collection
The root interface in the collection hierarchy.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
HashMap
Hash table based implementation of the `Map` interface.
HashSet
This class implements the `Set` interface, backed by a hash table (actually a `HashMap` instance).
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.print.event
Class
Description
EventObject
The root class from which all event state objects shall be derived.
Classes in java.util used by javax.script
Class
Description
Collection
The root interface in the collection hierarchy.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Map.Entry
A map entry (key-value pair).
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.security.auth
Class
Description
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.security.auth.callback
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by javax.security.auth.kerberos
Class
Description
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Classes in java.util used by javax.security.auth.login
Class
Description
Map
An object that maps keys to values.
Classes in java.util used by javax.security.auth.spi
Class
Description
Map
An object that maps keys to values.
Classes in java.util used by javax.security.auth.x500
Class
Description
Map
An object that maps keys to values.
Classes in java.util used by javax.security.cert
Class
Description
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Classes in java.util used by javax.security.sasl
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Map
An object that maps keys to values.
Classes in java.util used by javax.smartcardio
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by javax.sound.midi
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.sound.sampled
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Map
An object that maps keys to values.
Classes in java.util used by javax.sql
Class
Description
Calendar
The `Calendar` class is an abstract class that provides methods for converting between a specific instant in time and a set of `calendar fields` such as `YEAR`, `MONTH`, `DAY_OF_MONTH`, `HOUR`, and so on, and for manipulating the calendar fields, such as getting the date of the next week.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Map
An object that maps keys to values.
Classes in java.util used by javax.sql.rowset
Class
Description
Calendar
The `Calendar` class is an abstract class that provides methods for converting between a specific instant in time and a set of `calendar fields` such as `YEAR`, `MONTH`, `DAY_OF_MONTH`, `HOUR`, and so on, and for manipulating the calendar fields, such as getting the date of the next week.
Collection
The root interface in the collection hierarchy.
Map
An object that maps keys to values.
Classes in java.util used by javax.sql.rowset.serial
Class
Description
Map
An object that maps keys to values.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.sql.rowset.spi
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Classes in java.util used by javax.swing
Class
Description
Collection
The root interface in the collection hierarchy.
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
Dictionary
The `Dictionary` class is the abstract parent of any class, such as `Hashtable`, which maps keys to values.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Hashtable
This class implements a hash table, which maps keys to values.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.swing.event
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Classes in java.util used by javax.swing.plaf.basic
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
Hashtable
This class implements a hash table, which maps keys to values.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.swing.plaf.metal
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
Classes in java.util used by javax.swing.plaf.multi
Class
Description
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.swing.plaf.synth
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
Classes in java.util used by javax.swing.table
Class
Description
Comparator
A comparison function, which imposes a total ordering on some collection of objects.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.swing.text
Class
Description
Dictionary
The `Dictionary` class is the abstract parent of any class, such as `Hashtable`, which maps keys to values.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.swing.text.html
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.swing.text.html.parser
Class
Description
BitSet
This class implements a vector of bits that grows as needed.
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Hashtable
This class implements a hash table, which maps keys to values.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.swing.tree
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
EventListener
A tagging interface that all event listener interfaces must extend.
EventObject
The root class from which all event state objects shall be derived.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.swing.undo
Class
Description
EventListener
A tagging interface that all event listener interfaces must extend.
Hashtable
This class implements a hash table, which maps keys to values.
Vector
The `Vector` class implements a growable array of objects.
Classes in java.util used by javax.tools
Class
Description
Collection
The root interface in the collection hierarchy.
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
ServiceLoader
A facility to load implementations of a service.
Set
A collection that contains no duplicate elements.
Classes in java.util used by javax.xml.crypto
Class
Description
Iterator
An iterator over a collection.
Classes in java.util used by javax.xml.crypto.dom
Class
Description
Iterator
An iterator over a collection.
Map.Entry
A map entry (key-value pair).
Classes in java.util used by javax.xml.crypto.dsig
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by javax.xml.crypto.dsig.keyinfo
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by javax.xml.crypto.dsig.spec
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Classes in java.util used by javax.xml.datatype
Class
Description
Calendar
The `Calendar` class is an abstract class that provides methods for converting between a specific instant in time and a set of `calendar fields` such as `YEAR`, `MONTH`, `DAY_OF_MONTH`, `HOUR`, and so on, and for manipulating the calendar fields, such as getting the date of the next week.
Date
The class `Date` represents a specific instant in time, with millisecond precision.
GregorianCalendar
`GregorianCalendar` is a concrete subclass of `Calendar` and provides the standard calendar system used by most of the world.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
TimeZone
`TimeZone` represents a time zone offset, and also figures out daylight savings.
Classes in java.util used by javax.xml.namespace
Class
Description
Iterator
An iterator over a collection.
Classes in java.util used by javax.xml.stream
Class
Description
Iterator
An iterator over a collection.
Classes in java.util used by javax.xml.stream.events
Class
Description
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by javax.xml.stream.util
Class
Description
Iterator
An iterator over a collection.
Classes in java.util used by javax.xml.transform
Class
Description
Properties
The `Properties` class represents a persistent set of properties.
Classes in java.util used by javax.xml.xpath
Class
Description
Iterator
An iterator over a collection.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by jdk.dynalink
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
ServiceConfigurationError
Error thrown when something goes wrong while locating, loading, or instantiating a service provider.
Classes in java.util used by jdk.dynalink.beans
Class
Description
Set
A collection that contains no duplicate elements.
Classes in java.util used by jdk.dynalink.linker
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by jdk.dynalink.linker.support
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Classes in java.util used by jdk.javadoc.doclet
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Set
A collection that contains no duplicate elements.
Classes in java.util used by jdk.jfr
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by jdk.jfr.consumer
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Classes in java.util used by jdk.jshell
Class
Description
Collection
The root interface in the collection hierarchy.
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Set
A collection that contains no duplicate elements.
Classes in java.util used by jdk.jshell.execution
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Classes in java.util used by jdk.jshell.spi
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Optional
A container object which may or may not contain a non-`null` value.
Classes in java.util used by jdk.jshell.tool
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Map
An object that maps keys to values.
Classes in java.util used by jdk.management.jfr
Class
Description
List
An ordered collection, where the user has precise control over where in the list each element is inserted.
Map
An object that maps keys to values.
Classes in java.util used by jdk.net
Class
Description
Set
A collection that contains no duplicate elements.
Classes in java.util used by org.xml.sax
Class
Description
Locale
A `Locale` represents a specific geographical, political, or cultural region.
Classes in java.util used by org.xml.sax.helpers
Class
Description
Enumeration
An object that implements the Enumeration interface generates a series of elements, one at a time.
Locale
A `Locale` represents a specific geographical, political, or cultural region.