Array tools
Array operation provides several tools method
Arrays.toString(a)
The data in the array, a connection to a string
"[Value 1, value 2 and value 3, value 4]"
Arrays.sort(a)
Sorting an array
Quick Sort primitive array optimization
Merge sort array of reference types, optimized
Arrays.binarySearch(a, t)
A binary search, binary search
In an ordered array, subscript find the target location,
Can not find, return - (insertion point +1)
Arrays.copyOf (a, specified length)
The array, into a new copy of the specified array length