package lab5;

/**
 *	SearchArray implements a linear search in an array, searching
 *	for a user provided value.
 *
 *	Class Invariants:
 * 	'maxVal' must be greater than 'minVal'
 *	All elements of the array must lie in the range defined by 
 *	 	'minVal' and 'maxVal' variables
 *	@author
 *	@version Mar 3, 2012
 *	@project CMSC 202 - Spring 2012 - Project #
 *	@section #
 *
 */
public class SearchArray {
	private int array[],minVal,maxVal;
	boolean constructed=false;
	/**
	 * Assigns the instance variable array reference to 
	 * point to the incoming array reference. Also assigns the 
	 * range values.
	 * Precondition: The input array to the constructor cannot be null.
	 * @param array The input array to be searched on.
	 * @param minVal The minimum allowed value in the array.
	 * @param maxVal The maximum allowed value in the array.
	 */
	public SearchArray(int[] array, int minVal, int maxVal) {
		
		//Precondition checking code
		if(array==null){
			throw new NullPointerException("Constructor 
precondition " +
					"not met: Input array cannot be null");
		}
		
		//class invariant #1 checking code
		if(maxVal<minVal){
			throw new RuntimeException("Class invariant " +
					"not met: maxVal cannot be less than minVal");
		}
		
		/*
		 * Insert class invariant #2 checking code here
		 */
		
		this.array=array;
		this.minVal=minVal;
		this.maxVal=maxVal;
		constructed=true;
		System.out.println("\tSearchArray object successfully 
initialized");
	}
	
	
	/**
	 * Method to search for a number in the array.
	 * Precondition: the least possible value of x can be minVal and
	 * 		the max possible value can be maxVal.
	 * @param x The number to be searched
	 */
	public void search(int x){
		if(constructed){
			/*
			 * Enter Pre-condition checking code here
			 */
			
			boolean found=false;
			int i=0;
			while(found==false){
				if(array[i]==x){
					found=true;
				}
				i++;
			}
			if(found==true){
				System.out.println("\tElement " + x + " found 
at position " + --i);
			}else
				System.out.println("\tElement " + x + " not 
found");
		}
	}
	/**
	 * @param args
	 */
	public static void main(String[] args) {
		SearchArray s;
		
		/*
		 *Enter test case to check class invariant #2 
		 */
		
		//test case to check class invariant#1
        /*            
		System.out.println("Passing minVal>maxVal. Expecting error statement.");
		int[] testArray1={1,2,3,4,5};
		s=new SearchArray(testArray1, 10, 9);
        */
		
		//test case to check constructor precondition 
        /*
		System.out.println("Passing null array. Expecting error statement.");
		int[] testArray2=null;
		s=new SearchArray(testArray2, 0, 100);
        */
		
		//test case to check edge values of the constructor
		System.out.println("Edge case for constructor. Array values " +
				"exactly on range limits");
		int[] testArray3={-5,-9,0,-1,3,6,7,-2,2};
		s=new SearchArray(testArray3, -9, 7);
		
		//test case to check general values of the constructor
		System.out.println("General test case for constructor");
		int[] testArray4={-5,-6,0,-1,3,6,7,-2,2,3,4,7,-8};
		s=new SearchArray(testArray4, -9, 10);
		
		/*
		 * General test case(s) for search()
		 */
		
		/*
		 * Precondition checking test case for search()
		 */
		
		/*
		 * Edge test case for search()
		 */

	}

}