Does Java have a Bitmap class? [duplicate]

Question

I have been searching google for stuff like "Java Bitmap", "Create Java Bitmap", etc and cannot seem to find much information. From all of the code examples it looks like all of the bitmap libraries are third party or for android.

What I want to do is very simple. I want to create a small bitmap maybe 10x80, and be able to color each pixel at (x,y). I want to make a small I guess color bar that will show that position of items in a queue by color.

Are there any build in libraries to do this?

Answer 1

Here is an example of creating and writing to pixels with BufferedImage:

BufferedImage image = new BufferedImage(10, 80, BufferedImage.TYPE_4BYTE_ABGR);
image.setRGB(5, 20, Color.BLUE.getRGB());

The third parameter on the image is the type, which may vary based on your use, but for basic solid colors the one shown is good. The setRGB uses an int representation of the color so you can't just use a Color constant directly.

You probably don't want to use VolatileImage because the benefits are dubious in current Java implementations. See this stackoverflow question for why it may not help.

Look at the Oracle image turorial for help with this. It explains both your options and how to interact with them.

Answer 2

There's the java.awt.image.BufferedImage class. This has pixel-specific get/set methods. http://docs.oracle.com/javase/7/docs/api/java/awt/image/BufferedImage.html