使用Book对象的链接列表进行插入排序

Question

I'm trying to use insertion sort to sort linked list of Book alphabetically by title.

what I have done so far:

 public void insertSorted(Book book){
     if(books.getfirst()==null)
         books.addFirst(book); //books is the LinkedList name
     Node<Book> current =books.getfirst();
     for(int i=0; i<books.getSize(); i++){
        if(book.getTitle().compareToIgnoreCase(current.element.getTitle())<=0){
             books.add(book, i);

         }
     }

the add method in Linkedlist:

public void add(Object x,int index){
    if(index==0)addFirst(x);
    else if(index>=getSize())addLast(x);
    else{
        Node current=first;
        for(int i=0; i<index-1;i++)
            current=current.next;
        Node temp = new Node(x);
        temp.next=current.next;
        current.next=temp;
        count++;
    }
}

what exactly I'm doing wrong?

Answer 1

for(int i=0; i<books.getSize(); i++){
    if(book.getTitle().compareToIgnoreCase(current.element.getTitle())<=0){
         books.add(book, i);

     }

With this statement (above), you are not incrementing the current Node which is being compared. On each iteration of the for(;;) loop, you are comparing the new Book which is being added to this first element in the List .

The below code example should fix this:

for(int i=0; i<books.getSize(); i++){
    if(book.getTitle().compareToIgnoreCase(current.element.getTitle())<=0){
         books.add(book, i);
         break;
     }
    else {
        current = current.next;
    }

EDIT: Included required break statement, as per @Eden Lu answer

Answer 2

After you add the book to books, you need to break the loop

books.add(book,i); break;