The following text was written to the standard output stream when the ShapesThing.java program was executed from IntelliJ.
square=Square: side=400.0> area of square=160000.0 perimeter of square=1600.0 diagonal of square=565.685424949238 disk=Circle: radius=200.0> area of disk=125663.70614359173 perimeter of disk=1256.6370614359173 diamond=Square: side=282.842712474619> area of the diamond=80000.0