//----------------------------------------------------------------------------
// StackInterface.java           by Dale/Joyce/Weems                 Chapter 3
//
// Interface for a class that implements a stack of <T>.
// A stack is a last-in, first-out structure.
// ajg version: format
//----------------------------------------------------------------------------

package ch03.stacks;

public interface StackInterface<T> {

    // Throws StackUnderflowException if this stack is empty,
    // otherwise removes top element from this stack.
    void pop() throws StackUnderflowException;
  
    // Throws StackUnderflowException if this stack is empty,
    // otherwise returns top element from this stack.
    T top() throws StackUnderflowException;

    boolean isEmpty();
}