Introduction to Programming

Search and equals() 

There are five static search-related methods in the class Collections:

• int binarySearch(List<Comparable<T>> list, T key)
• int binarySearch(List<T> list, T key, Comparator<T> comparator)
• int indexOfSubList(List<?> source, List<?> target) 
• int lastIndexOfSubList(List<?> source, List<?> target)
• int frequency(Collection<?> collection, Object object)

The binarySearch() methods search for the key value in the provided list. The important thing to notice is that the provided list must be sorted in ascending order because of the nature of the binary search. The algorithm compares the key to the middle element of the list; if they are unequal, the half in which the key cannot belong is ignored and the algorithm compares the key ...