What is abstract window toolkit (AWT)? Present AWT class hierarchy showing all components and containers.

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 Java AWT (Abstract Windowing Toolkit) is an API to develop GUI or application in java. Java AWT components are platform-dependent i.e. components displayed according to the view of the operating system. AWT is heavyweight i.e. its components use the resources of the system. Actually, AWT calls native platform (Operating system subroutine for creating components such as textbox, checkbox, button, etc. For example, if we an instantiating a text box in AWT that means we are actually asking OS to create a text box for you. This is the reason why AWT components look different on different operating systems. simple, an application built on AWT would look like a windows application when it runs Windows, but the same application would look like a Mac application when runs on Mac OS.

AWT CLASSES

The java.awt package provides classes for AWT API such as TextField, Label, TextArea RadioButton, CheckBox, Choice, List, etc. AWT is rarely used nowadays because of its platform-dependent and heavy-weight nature. The java.awt package contains the core AWT graphic classes:

  • GUI Component classes (such as Button, TextField, and Label)
  • GUI Container classes (such as Frame, Panel, Dialog and ScrollPane)
  • Layout managers (such as FlowLayout, BorderLayout and GridLayout)
  • Event Handling Classes (such as AWTEvent, AWTEventMultiCaster)
  • Custom graphics classes (such as Graphics, Color and Font).

The ultimate superclass of all the GUI components both in AWT as well as Swing is the java.awt.Component. The hierarchy of widely used Java AWT classes is given below:



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