Question

I need to write a method that sorts a provided Linked list with bubble sort and using ONLY Java List Iterator Methods (Link Below)

https://docs.oracle.com/javase/8/docs/api/java/util/ListIterator.html  

  public static <E extends Comparable<? super E>> void bubbleSort(List<E> c) throws Exception {

    // first line to start you off

    ListIterator<E> iit = c.listIterator(), jit;

    /**** Test code: do not modify *****/

    List cc = new LinkedList(c);

    Collections.sort(c);

    ListIterator it1 = c.listIterator(), it2 = cc.listIterator();

while (it1.hasNext()) {

if (!it1.next().equals(it2.next()))

        throw new Exception("List not sorted");

}

    /***********************************/

  }

Answer 1

Here is the completed code for this method. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

//required method implementation

public static <E extends Comparable<? super E>> void bubbleSort(List<E> c)

                                throws Exception {

                // first line to start you off

                ListIterator<E> iit = c.listIterator(), jit;

                int index = 0; // index of current element the iterator iit is iterating

                // looping until list is fully sorted

                while (iit.hasNext()) {

                                System.out.println(c);

                                // getting an iterator

                                jit = c.listIterator();

                                // declaring two E objects to null

                                E ob1 = null, ob2 = null;

                                // setting ob1 to first element

                                if (jit.hasNext()) {

                                               ob1 = jit.next();

                                }

                                // loops as long as there is an element left to read

                                while (jit.hasNext()) {

                                               ob2 = jit.next();

                                               // comparing ob1 and ob2

                                               if (ob1.compareTo(ob2) > 0) {

                                                               // ob1 and ob2 needs to be swapped

                                                               // this can be done by removing last two values iterated and

                                                               // adding in reverse order

                                                               jit.previous();

                                                               jit.previous(); // now the iterator cursor is at ob1

                                                               // removing ob1

                                                               jit.remove();

                                                               // moving to ob2

                                                               jit.next();

                                                               // removing ob2

                                                               jit.remove();

                                                               // adding ob2, and then ob1

                                                               jit.add(ob2);

                                                               jit.add(ob1);

                                                               // resetting iit so that ConcurrentModificationException is

                                                               // not thrown, starting iteration from index 'index'

                                                               iit = c.listIterator(index);

                                               } else {

                                                               ob1 = ob2;

                                               }

                                }

                                //calling next element in iit, updating index

                                iit.next();

                                index++;

                }

                /**** Test code: do not modify *****/

                List cc = new LinkedList(c);

                Collections.sort(c);

                ListIterator it1 = c.listIterator(), it2 = cc.listIterator();

                while (it1.hasNext()) {

                                if (!it1.next().equals(it2.next()))

                                               throw new Exception("List not sorted");

                }

}