What is Java API?

#Java API: Java Application Programming Interface
(API) is the part of Java development kit (JDK).
An API consists of classes, interfaces, packages along with its methods, fields, and constructors.
These inbuilt classes provide the functionalities to a developer.
Only developers know that how to implement that class.
A user interface provides the simple user interaction between user and computer in the
same way the API act as a software program interface which provides interaction between the
application and the user.
API consists of classes and packages which helps a developer to reduce the lines of code.
Java Development Kit (JDK) is comprised of three basic components, as follows:
1. Java compiler
a. Java Virtual Machine (JVM)
i. Java Application Programming Interface (API)
The Java API, included with the JDK, describes the function of each of its components. In Java
programming, many of these components are pre-
created and commonly used.
Thus, the programmer is able to apply prewritten
code via the Java API.
After referring to the available API classes and
packages, the programmer easily invokes the
necessary code classes and packages for
implementation.
The Java API is the most important part of JDK and
describes the functionality of each component.
While Programming in Java, the component is
already created and used it.
Through the Java, API programmer can easily apply
the pre written code.
The programmers first declare the classes and
packages then the programmers can easily invoke
the related code of classes and packages for
implementation.

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