The sun.misc.Unsafe class, like other sun classes, is not officially documented or supported. It has been used to circumvent some of Java's built-in memory management safety features. While this can be viewed as a window to greater control and flexibility in our code, it is a terrible programming practice.
The class had a single private constructor, so an instance of the class could not easily be instantiated. So, if we tried to instantiate an instance with myUnsafe = new Unsafe(), a SecurityException would be thrown in most circumstances. This somewhat unreachable class has over 100 methods that permitted operations on arrays, classes, and objects. Here is a brief sampling of those methods:
Arrays | Classes ... |