BooleanStack.java

public class BooleanStack {

	private boolean Stack[];
	private int StackPosition;
	
	public BooleanStack() {
		this.StackPosition = -1;	
	}
	
	public BooleanStack(int Length) {
		this.Stack = new boolean[Length];
		this.StackPosition = -1;   // StackPosition represents the position of the current element in the stack
							// -1 means there are no elements.
	}
	
	public void push(boolean pushme) {
		if(StackPosition<=Stack.length-1) {
			if(this.StackPosition == Stack.length-1) {
				boolean temp[] = new boolean[2*Stack.length];
				for(int i=0; i<Stack.length; i++) temp[i] = Stack[i]; 
				Stack = temp;
				Stack[++StackPosition] = pushme;
			}
			else
				Stack[++StackPosition] = pushme;
		}
	}
	
	public void print_stack() {
		for(int i=0; i<=StackPosition; i++) System.out.print(Stack[i] + " ");
		System.out.println();			 
	}
	
	public void replace(int position, boolean pushme) {
		if(position <= StackPosition)
			Stack[position] = pushme;
		else
			System.out.println("Invalid position.  The position is beyond the Stack Position");
	}
	
	public boolean access(int position) {
		if(position <= StackPosition)
			return Stack[position];
		else {
			System.out.println("Invalid position. cannot return a value returning a false value");
			return false;
		}
	}
	
	public boolean check(boolean Value) {
		for(int i=StackPosition; i>=0; i--) {
			if(Stack[i] == Value) return true;
		}
		return false;
	}
	 
	public boolean check(int position, boolean Value) {
		if(position <= StackPosition & position >=0)
			return (Stack[position] == Value);
		else {
			System.out.println("Invalid position. returning a false");
			return false;
		}
	}
	
	
	public void ChangeStackPosition(int NewPosition) {
		if( NewPosition < -1 || NewPosition > Stack.length-1 )
			System.out.println("Invalid position in the stack. Cannot change to the position.");
		else
			StackPosition = NewPosition;
	}           ////////   Send -1 as argument to this function to reset the stack.  
	
	public int noofelements() {
		return (StackPosition+1);
	} 
	
	
	 
}