For handling i/o of an application in java , java.io & java.nio package is available.
Object Serialization provides the of objects' encoding into the stream of byte and also provide us the support for the object graph's reconstruction.
This package provide us the network's functionality and networking security functionality. The network functionality includes addressing, URLs & URIs classes etc.
This package provide us APIs for enhancing security related issues for example secure Internet communication, authentication and authorization, configurable access control, digital signing, cryptography.
This API provide us support for internationalization of the application.
JavaBeans Component API
The JavaBeans Component API provide us classes and components ,based on the architecture of JavaBeans, which is used for the development of the beans.
Java Management Extensions (JMX)
For monitoring and managing resources we incorporate this API which is termed as Java Management Extensions (JMX). Examples are monitoring and management of JVM, applications, services, devices etc.
This API termed as JAXP is used for processing of XML data and documents.
Java Native Interface (JNI)
JNI stands for Java Native Interface is an interface which is used for planting JVM into Native application and also for writing native methods of java.
This Extension Mechanism provides ability to JVM to incorporate optional extension classes.
Endorsed Standards Override Mechanism
This standard provide us the API in which standard processes are defined which is different from JCP(Java Community Process)
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