Note that equal objects must have equal hash codes. Therefore, when overriding the equals method, you must also override the hashCode method. Failure to do so violates the general contract for the hashCode method, and any classes that use the hash code, such as HashMap will not function properly.
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes: 1  electro-magnetic radiation (also known as continuum radiation) Î³ such as radio waves, visible light, and x-rays.
This lesson defines and describes radiant energy in its different forms. The different types of electromagnetic waves created by radiant energy are identified and described as well. This includes X-rays, microwaves, and radio waves, to mention a few.