Papillary thyroid cancer (also sometimes called papillary thyroid carcinoma) is the most common type of thyroid cancer. You may have even heard your doctor talk about metastatic papillary thyroid cancer (metastatic means that it has spread beyond your thyroid gland).
Classes can have special methods called constructors. A constructor is a method that is automatically called when an object is created. Constructors are used to perform operations at the time an object is created. Constructors typically initialize instance fields and perform other object initialization tasks.
When an object is created without initialization, it is called a Null object, and the use of such null objects can become a cause of Null Pointer Exceptions. At this point, you may choose to take an online course and learn Java from Scratch in order to learn the basics of Java primitives and their initialization.