Uses of Class
java.lang.FunctionalInterface

Packages that use FunctionalInterface 
Package Description
java.awt
Contains all of the classes for creating user interfaces and for painting graphics and images.
java.io
Provides for system input and output through data streams, serialization and the file system.
java.lang
Provides classes that are fundamental to the design of the Java programming language.
java.net.http
HTTP Client and WebSocket APIs
java.nio.file
Defines interfaces and classes for the Java virtual machine to access files, file attributes, and file systems.
java.security
Provides the classes and interfaces for the security framework.
java.time.temporal
Access to date and time using fields and units, and date time adjusters.
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.function
Functional interfaces provide target types for lambda expressions and method references.
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.
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.nashorn.api.tree
Nashorn parser API provides interfaces to represent ECMAScript source code as abstract syntax trees (AST) and Parser to parse ECMAScript source scripts.