The Project
For this assignment, you will write the LinearList class, a singly linked list based implementation of the LinearListADT interface (given below). A 'list' is a sequence of values. The ordering of the items in the list is not specified but does matter, and is in fact problem dependent. No insertion ever occurs at an arbitrary location. When an item is removed from the list, the ordering of the remaining elements in the list is unchanged.
We want to segregate our data structures and separate them from any application programs. Accordingly, you must place all data structures in a package nameddata_structures. Your LinearList class must implement the LinearListADT interface. Your project will consist of exactly the following two files, both of which must be in a data_structures/ package:
? LinearListADT.java The linear list interface (provided below)
? LinearList.java Your implementation of the this interface
Both of the above files must go in package data_structures. Any driver/tester programs will go in the level above the data_structures subdirectory. [ The sample tester program provided for assignment #1 will also work for this one. ] IMPORTANT: The package organization is of critical importance. If your project fails to compile during the grading process due to package errors, your grade for this project
will be zero.
The LinearListADT interface:
/* Your name
Your masc account number
*/
package data_structures;
import java.util.Iterator;
import java.util.NoSuchElementException;
public interface LinearListADT extends Iterable {
public static final int DEFAULT_MAX_CAPACITY = 100;
// Adds the Object obj to the end of list.
public void addLast(E obj);
// Adds the Object obj to the beginning of list.
public void addFirst(E obj);
// Inserts the Object obj at the position indicated. If there is an element at
// that location, all elements from that location to the end of the list are
// shifted down to make room for the new insertion. The location is one based.
// If the location > size()+1 then a RuntimeException is thrown. List elements
// must be contiguous.
public void insert(E obj, int location);
// Removes the object located at the parameter location (one based).
// Throws a RuntimeException if the location does not map to a valid position within the list.
public E remove(int location);
// Removes and returns the parameter object obj from the list if the list contains it, null otherwise.
// The ordering of the list is preserved. The list may contain duplicate elements. This method
// removes and returns the first matching element found when traversing the list from first position.
public E remove(E obj);
// Removes and returns the parameter object obj in first position in list if the list is not empty,
// null if the list is empty. The ordering of the list is preserved.
public E removeFirst();
// Removes and returns the parameter object obj in last position in list if the list is not empty,
// null if the list is empty. The ordering of the list is preserved.
public E removeLast();
// Returns the parameter object located at the parameter location position (one based).
// Throws a RuntimeException if the location does not map to a valid position within the list.
public E get(int location);
// Returns true if the parameter object obj is in the list, false otherwise.
public boolean contains(E obj);
// Returns the one based location of the parameter object obj if it is in the list, -1 otherwise.
// In the case of duplicates, this method returns the element closest to position #1.
public int locate(E obj);
// The list is returned to an empty state.
public void clear();
// Returns true if the list is empty, otherwise false
public boolean isEmpty();
// Returns the number of Objects currently in the list.
public int size();
// Returns an Iterator of the values in the list, presented in
// the same order as the underlying order of the list. (position #1 first)
public Iterator iterator();
}
Additional Details
? The DEFAULT_MAX_CAPACITY constant in the interface is not applicable to this implementation.
Linked lists are never full unless the user has exhausted all available memory. You are not
responsible for this situation, nor do you need to test for it. It should also be obvious that the
array resizing operations needed for the first version are not applicable here.
? All references to list element position are one-based, not zero-based. The first element in the list
is at position #1, not #0.
? The ordering of the elements in the list is user defined. Thus, you must never alter the ordering
of items in the list internally.
? Your LinearList class will have a single constructor that takes no arguments.
? Both files specified in this assignment must have the exact names and signatures as given.
? You must not make any changes to the LinearListADT interface; I will use my copy to compile
and run your program.