BinarySearch.java

package noun;


import algorithms.LargerSorter;
import algorithms.MediumSorter;
import algorithms.SmallSorter;
import algorithms.ISorter;

public class BinarySearch {
	
	ISorter sc;
	int array[];
	
	public BinarySearch(){}
	
	public void setArray(int array[]){
		
		//Instead of this, you could also set type, dynamically.
		
		if(array.length <= 100)
			sc = new SmallSorter();
		
		else if(array.length<=2500)
			sc = new MediumSorter();
		
		else 
			sc = new LargerSorter(); // parallel sort is efficient if the array size is 2500
		
		/*  can also perform, something similar, with compression algorithm, cryptography etc
		 * 	i.e. compression  : based on the file size
		 *     	 cryptography : based on available memory etc. 
		 *     
		 *  Reference :https://stackoverflow.com/questions/370258/real-world-example-of-the-strategy-pattern
		 *  This is the core part.
		*/
		this.array = array;
		
		sc.sort(this.array); 
	}
	
	public int search(int val){
		
		int low, high, mid;
		low  = 0;
		high = this.array.length;
		
		while(low <= high){
			
			mid = (low + high)/2;
			
			if(this.array[mid] == val)
				return mid; // need to handle duplicate value scenario
      
			else if( this.array[mid] < val)
				low = mid+1;
			
      else
				high = mid-1;
			
		}
		
		return -1;
	}
	
}