NumberList.java

// File Name: NumberList.java
//
// Author: Quinn Zipse
//
// Uses inner classes to try and hide the list data structure from the public
// 
public class NumberList {
    private NumberNode head;

    private NumberList(NumberNode head){
        this.head = head;
    }

    public int get(int index){
        if(index < size()) {
            NumberNode temp = head;
            for (int i = 0; i < index; i++) {
                temp = temp.getNext();
            }
            return temp.getNum();
        } else {
            throw new IndexOutOfBoundsException();
        }
    }

    @Override
    public String toString() {
        NumberNode temp = head;
        StringBuilder result = new StringBuilder("{");
        for(int i=0; i<this.size(); i++){
            if(i>0){
                result.append(", ");
            }
            result.append(temp.getNum());
            temp = temp.getNext();
        }
        result.append("}");

        return result.toString();
    }

    public void add(int index, int num){
        if(index < size()+1){
            NumberNode pos = head;
            for(int i=1; i<index; i++){
                pos = pos.getNext();
            }
            NumberNode temp = new NumberNode(num, pos.getNext());
            pos.setNext(temp);
        } else {
            throw new IndexOutOfBoundsException();
        }

    }

    public void remove(int index){
        if(index < size()){
            NumberNode pos = head;
            for(int i=1; i<index; i++){
                pos = pos.getNext();
            }
            pos.setNext(pos.getNext().getNext());
        } else {
            throw new IndexOutOfBoundsException();
        }

    }

    public NumberList newReverse(){
        NumberNode prev = null, temp;
        for(NumberNode pos = head; pos!= null; pos = pos.getNext()){
            temp = new NumberNode(pos.getNum(), prev);
            prev = temp;
        }
        return new NumberList(prev);
    }

    public void reverse(){
        NumberNode pos, next, prev=null;
        for(pos = head; pos!=null; pos = next){
            next = pos.getNext();
            pos.setNext(prev);
            prev = pos;
        }
        head = prev;
    }

    public int size(){
        int i=0;
        for(NumberNode pos = head; pos!= null; pos = pos.getNext()){
            i++;
        }
        return i;
    }

    private static class NumberNode {
        private NumberNode next;
        private int num;

        public NumberNode(int num, NumberNode next) {
            this.num = num;
            this.next = next;
        }

        public NumberNode(int num) {
            this(num, null);
        }

        public NumberNode() {
            this(0, null);
        }

        public NumberNode getNext() {
            return next;
        }

        public void setNext(NumberNode next) {
            this.next = next;
        }

        public int getNum() {
            return num;
        }

        public void setNum(int num) {
            this.num = num;
        }
    }

    public static void main(String[] args) {
        NumberList list = new NumberList(new NumberNode(2, new NumberNode(3, new NumberNode(4))));
        System.out.println(list.toString());
        System.out.println(list.newReverse().toString());
        list.reverse();
        System.out.println(list.toString());
        System.out.println(list.get(1));
        list.add(1, 100);
        System.out.println(list.toString());
        list.remove(1);
        System.out.println(list.toString());
    }

}