In windows L&F(Using OS Windows 2000) Selected color mark of JCheckBox and 
JRadioButton are not same as native.
These both components are using selected mark color as RGB 66, 65, 66 i.e color
dark gray, while in native selected mark color is black i.e. RGB 0, 0, 0

Consider attached image: CheckRadioCmp.PNG
It clearly shows this difference.

This is a similar problem to 5018688.
  xxxxx@xxxxx   2004-03-24

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Posted Date : 2005-09-09 16:47:39.0

Note, the following only applies to Win2k or when running WinXP using the Classic themeset:

The root of this problem is that the check of the checkbox is being drawn using the darkShadow color. With the Windows Classic theme the darkShadow color was black, so it looked fine. With the Windows Standard theme the darkShadow has changed to a dark gray, so the check is drawn differently.  A native windows app will still draw using black.  

Normally this isn't noticable but if you switch to one of the stranger themes like High Contrast #2 which uses inverse color and a green foreground we can see that the check should be drawn green but is still being drawn with the darkShadow color (in this case, white). This very noticable and should be fixed.  

With high contrast mode the native apps draw the check green as well, which implies that the check should be drawn with the foreground color. Thinking about it this makes sense. The check is essentially a kind of text inside the control and should be drawn with the same color as the other text. The solution is to change the code to use the CheckBox.foreground color instead of the CheckBox.darkShadow color.
Posted Date : 2005-09-12 18:24:48.0