RingList-AlgoDat-Verbessert

package blatt3;

import java.lang.Iterable;
import java.util.Iterator;

public class RingList<E> implements List<E> {
    private class Wrapper {
        E e;
        Wrapper succ;

        Wrapper(E e){
            this.e = e;
            succ = null;
        }
    }

    Wrapper first;
    Wrapper last;
    int size;

    RingList(){
        first = new Wrapper(null);
        last = first;
        last.succ = first;
        size = 0;
    }

    public boolean add(E e) {
        Wrapper w = new Wrapper(e);
        last.succ = w;
        last = w;
        last.succ = first;
        size++;
        return true;
    }

    public boolean remove(Object o) {
        Wrapper temp = first;
        Wrapper w = first.succ;
        for(int i = 0; i<size; i++) {
            if(o.equals(w.e)) {
                temp.succ = w.succ;
                if(i == size -1) {
                    last = temp.succ;
                }
                size--;
                return true;
            }
            temp = w;
            w = temp.succ;
        }
        return false;
    }

    public E remove(int index) {
        if(index >= size || index < 0) {
            throw new IndexOutOfBoundsException();
        }
        Wrapper temp = first;
        Wrapper w = first.succ;
        for(int i = 0; i<index; i++) {
            temp = w;
            w = temp.succ;
        }
        temp.succ = w.succ;
        if(index == size -1) {
            last = temp;
        }
        size--;
        return w.e;
    }

    public int indexOf(Object o) {
        Wrapper temp = first;
        Wrapper w = first.succ;
        for(int i = 0; i<size; i++) {
            if(o.equals(w.e)) {
                return i;
            }
            temp = w;
            w = temp.succ;
        }
        return -1;
    }

    public E get(int index) {
        Wrapper wRun;
        if (index < 0 || index >= size){
            throw new IndexOutOfBoundsException();
        }
        wRun = this.first.succ;
        for (int iRun = 0; iRun < index; iRun++){
            wRun = wRun.succ;
        }
        return wRun.e;
    }

    public int size() {
        return size;
    }

    public Iterator<E> iterator() {
        return new Iterator<E>(){
            Wrapper next = first.succ;
            Wrapper current;

            public boolean hasNext() {
                return next.e != null;
            }

            public E next() {
                current = next;
                if (next != null){
                    next = next.succ;
                }
                return current.e;
            }

            public void remove() {
                throw new UnsupportedOperationException();
            }
        };
    }
}


// MAIN KLASSE:

package blatt3;

import java.awt.Point;
import java.util.Iterator;

public class Main {

    public static void main(String[] args) {
        int n = 5;
        if (args.length > 0){
            n = Integer.parseInt(args[0]);
        }

        List<Integer> aList = new RingList<Integer>();

        for (int i = 0; i < n; i++){
            aList.add(i*i);
        }
        Integer num1 = new Integer(0);
        Integer num2 = new Integer(9);
        Integer num3 = new Integer(10);
//      System.out.println("Index of " + num1 + ": " + aList.indexOf(num1));
//      System.out.println("Index of " + num2 + ": " + aList.indexOf(num2));
//      System.out.println("Index of " + num3 + ": " + aList.indexOf(num3));
//      System.out.println("Remove " + num1 + ": " + aList.remove(num1));
//      System.out.println("Remove " + num2 + ": " + aList.remove(num2));
        System.out.println("Remove " + num3 + ": " + aList.remove(aList.size() -1));
        aList.add(99);

        /* Ausgabeschleife 1 fuer Integer-Liste aList */
        for (int i = 0; i < aList.size(); i++){
            System.out.println(aList.get(i));
        }
//      System.out.println("=======================");

//      for (int val: aList){
//          System.out.println(val);
//      }
//      System.out.println("=======================");
//
//      List<String> bList = new RingList<String>();
//
//      for (int i = 0; i < n; i++){
//          bList.add("als String " + i * i);
//      }
//      /* Ausgabeschleife 2 fuer String-Liste bList */
//      for (Iterator it = (Iterator) bList.iterator(); it.hasNext();){
//          System.out.println(it.next());
//      }
//      System.out.println("=======================");
    }
}