What is a framework?
Frameworks are large bodies (usually many classes) of prewritten code to which you add your own code to solve a problem in a particular domain. Maybe you could say that the framework uses your code because it's usually the framework that has control. Frame work is a essential part in core java training.
You use a framework by calling its methods, inheritance, and callbacks, listeners, or other implementations of the Observer pattern.
Contrast in the library. Although sometimes large libraries are referred to as frameworks, this is probably not the most common use of the term.
The distinction between framework and library is very well defined in Patterns and Software: essential concepts and terminology.


Java Framework

Using frameworks
A framework often determines the structure of your application. Some frameworks even provide so much code that you need to do very little, to write your application. This can be good or bad, depending on how easy it is to use. Wil Shipley says::
Frameworks are the content of programming. You build on a good, your program is solid and fast, and comes together beautifully. You're building up on a bad one, your life is miserable, Brutal, and short.

1. Spring Framework
Each Java Developer guarantees its ability to create complex, powerful web applications.
With simple components and configurations, this modular framework allows you to develop enterprise-level Java applications. Its DI-dependency injection function and compatibility with other frameworks such as Kotlin and Groovy make it a favorite of Java developers.
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2. Grail
Grails is a dynamic framework that is anchored by the Groovy JVM programming language. It works with Java technologies, including Java EE containers, Spring, SiteMesh, Quartz and Hibernate.
This open source Web development framework is very popular with Java developers for Enterprise Java Beans or EJB support. For this reason, the XML does not need to be configured, so that developers can quickly start creating a robust and scalable application.
3. Blade
This 2015-born framework is so simple and easy that every developer from a project perspective can understand it in a single day.
Based on Java 8, Blade, a lightweight MVC Framework provides a RESTful-style routing interface, making the web API cleaner and much easier to understand and synchronize data with the site.
4. Google Web Toolkit
GWT is a completely free Open source framework that allows developers to write client-side Java code and provide it as a JavaScript. Many Google products have been written with GWT like AdSense, AdWords, Google Wallet and bloggers.
5. JavaServer faces (JSF)
"This is good news for us, "he says, adding:"We are very happy with the course of the season." Developed by Oracle, it has a set of APIs for representing and managing UI components and custom tag library for expressing a JSF interface.
JSF is based on MVC software design pattern and has an architecture that clearly defines a distinction between application logic and representation.
6. Play
Its popularity can be estimated by the fact that it is used by top companies such as Samsung, LinkedIn, Verizon, the Guardian and more. Because it uses an asynchronous model that enables statelessness, play framework provides speed, performance, and scalability.
7. Aspire
Here is another enterprise-level framework managed by the Apache Software Foundation. This fully-featured Java Web Application Framework allows developers to create easy-to-maintain Java applications at the enterprise level.
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