CIS 3130 Home

CISC 3130
Data Structures
Sample Questions

Given a container class with a fixed-capacity underlying array, and an append (add to end) method.
- Declare the instance variables of the class. Assume the capacity is supplied by the constructor (i.e., not hard-coded in the declaration).
- When is the array created?
- Code the append method. Make sure you detect overflow and throw an exception.

What is wrong with the following checkCapacity code for a resizeable int-based container?

void checkCapacity() {
	if (size < capacity) return;
	int [] t = new int[capacity+1];
		
	for (int i = 0; i < size; i++)
		t[i] = arr[i];
	arr = t;
}

Given an interface named Container, two implementation classes, ContainerImp1 and ContainerImp2, and an interface-specific app, ContainerApp that have all been coded already, code the two implementation container apps using dependency injection.
Given a Set container with an underlying array container,
- - what is the order of the contains method assuming the array is maintained in unsorted order?
  - what is the order of the contains method assuming the array is maintained in sorted order?
- What is the tradeoff to using the representation with the 'better' method?
Write a demo program that creates, populates (100 elements), print, then empties a stack implemented using a JCF Deque. Deque has the following methods: addFirst, addLast, contains, getFirst, getLast, isEmpty, peekFirst, peekLast, pop, push, removeFirst, removeLast, size
Assuming the existence of a class, Stack, (with the usual behavior of a stack) write a method (not of the Stack class), clear(Stack stack), that accepts a stack and clears it (i.e. removes all its elements).
Explain the statement: in Java, methods that are not in an interface but are in a class implementing that interface should, in general, be declared private, are considered part of the implementation, and calling them from an application violates the principle of 'programming to the inteface'.