Custom GUI...Help?!

Hello , everyone.
This is my first post,and I am new to Java-and programming in general-, so I am looking forward to learn, and give advice where I can.

I need to create a GUI components from scratch, like a button, Text area etc. Instead,I figured that if I understand the Java components' source(from OpenJDK) I can customize them to my needs, instead of creating new ones.
Here is my problem:
I read the source code of JTextArea (and it's parents), but I cannot figure out how it draws the text!(I expected something like graphics.drawString , or any other method that performs the drawing).All calling to paint() in this class or parent classes, do not have anything that draws the text.

I ask this question because I don't want to develop a text component from scratch, because then I will have to deal with a lot of issues, and I can't find and source code for a simple Text Component.

Can anyone Help me plz?

Also,though outside the topic, Swing components do not have peer components , but all of them inherits from AWT.Compnent, and AWT components have peers, how can that be?!!!

All JComponents delegate their painting to a UI; for a JTextArea a TextUI does the drawing. That's why you don't see any drawing in the JTextArea itself. Those UIs are pluggable; different Look and Feel objects supply their own UIs for the JComponents.

Better extend an existing JComponent than building your own. The fist is much easier (but it depends on what you want to do) than the latter.

kind regards,

Jos