实现Convex　Hull算法的JAVA源代码。

A Convex Hull is the smallest convex polygon that contains every point of the set S. A polygon P is convex if and only if, for any two points A and B inside the polygon, the line segment AB is inside P. One way to visualize a convex hull is to put

由一堆离散点，自动生成它的最小外包多边形，及凸壳。-By a bunch of discrete points, it is automatically generated out of the smallest polygon, and the Convex Hull.

In this project, three convex hull algorithms are implemented in java. Three algorithms are Brute Force, Graham’s Scan and Jarvis’ March.