Drawing or Graphics APIs form an integral part of any language. They let you access the host operating system's GUI services. They are needed not only for implementing and rendering custom GUI controls and components for a standalone system; they also provide for non-GUI control based applications such as image manipulation, graph rendering functions and so on. Among current languages almost all provide drawing APIs. Java is no exception.
Getting Started with Java 2D - Image Processing (Page 3 of 4 )
Until Java 2D came along, image processing was a difficult endeavor in Java. However, the 2D API has changed all that. It provides the following functionalities:
Images
Image processing
Printing
The main difference between the first and second is that former provides basic image manipulation techniques whereas the latter provides advanced techniques for processing and manipulating digital images.
Concerning images, with Java 2D one can do all the manipulation one can do with shapes and text, which includes transformations such as scaling, rotating and so forth, as well as clip images using shapes. One can also use alpha compositing with images.
Java 2D provides set of classes for processing images. Image processing essentially means enhancing certain aspects of a given image as well as aesthetically enhancing the image. Using 2D API this can be done easily and effectively.
Printing was an aspect that Java didn't support well. However, the Printing API that is a part of Java 2D provides a compact and clean solution for producing prints on a printer.
That covers the functionality provided by Java 2D. Now let's look at the steps we'll need to take to make use of these functionalities.
Java 
Swing Animation
