How can I make a graphic object transparent, that is, control the alpha value or make it "see-through"?
Java provides support for alpha values in the java.awt.Color class. This can be used to control the opacity of JViews graphics through their setForeground() and setBackground() methods.
Often you will want to control opacity for a group of graphics at one time. JViews provides a convenient method on its layers for this purpose: ilog.views.IlvManagerLayer.setAlpha(float). This sets the alpha value for all the objects on a layer (0.0 = invisible, 1.0 = solid).
Here is some code that sets the transparency level for a layer to 25%: