// method to return the top element of the stack

public Object peek() {

if (!isEmpty())

return stack[top];

return null;

}

// method to insert element at top of the stack

public void push(Object data) {

if (!isFull()) {

top++;

stack[top] = data;

} else

System.out.println(" Stack is full");

}

// method to delete top element of the stack

public Object pop() {

if (!isEmpty()) {

Object data = stack[top];

top--;

return data;

} else {

System.out.println(" Empty Stack");

return null;

}

}

// method to get the number of elements in the stack

public int getSize() {

return (top + 1);

}

// method to get the total capacity of the stack

public int getCapacity() {

return stack.length;

}

// method to get the remaining number of elements that can be inserted in the

// stack

public int getRemainingCapacity() {

return (getCapacity() - getSize());

}

// method to check if the stack is full

public boolean isFull() {

return (getRemainingCapacity() == 0);

}

// method to check if stack is empty

public boolean isEmpty() {

return (top == -1);

}

// method to return the string representation of the stack

public String toString() {

if (isEmpty()) {

return "Empty Stack";

} else {

String stkStr = "";

int i = top;

while (i >= 0) {

stkStr += stack[i] + " ";

i--;

}

return stkStr;

}

}

// method to add all the elements of the passed array to the stack, return true

// if successful else false

public boolean addAll(Object[] arr) {

if (getRemainingCapacity() == arr.length) {

for (int i = 0; i

push(arr[i]);

return true;

}

return false;

}

// method to return if the passed object is present in the stack

public boolean contains(Object obj) {

for (int i = top; i >= 0; i--)

if (stack[i].equals(obj)) {

return true;

}

return false;

}

// method to return if all the elements in passed object array are present in

// the stack or not

public boolean containsAll(Object[] arr) {

for (int i = 0; i

if (!contains(arr[i])) {

return false;

}

return true;

}

// method to return an array representation of the stack where index 0 is the

// bottom of the stack

public Object[] toArray() {

if (isEmpty()) {

return null;

}

Object stk[] = new Object[top + 1];

for (int i = 0; i

stk[i] = stack[i];

return stk;

}

}

Java Code

Need Junit 4 test Cases for the above methods example of one of them is