Add a linked list to another linked list in java

Question

I am trying to add a linkedlist to another linkedlist using a method called addList in the MyLinkedList class. What I'm stuck on is how to implement the method so that I can add a linkedlist to another linkedlist of index location of my choosing.

Here's what I have in MyLinkedList:

public void addList(int index, E e){
 if(index == 0){
 addFirst(e);
 } else if (index >= size){
 addLast(e);
 }
 else{
 Node<E> current = head;
 for(int i = 1; i < index; i++){
 current = current.next;
 }
 Node<E> temp = current.next;
 current.next = new Node<E>(e);
 (current.next).next = temp;
 size++;
 }
}

I know this method won't work, I've tried it. In my program itself, I have these:

public class linkedlistwork {
 public static void main(String[] args) {
 MyLinkedList<String> alpha = new MyLinkedList<String>();
 alpha.add("hello");
 alpha.add("world");
 alpha.add("this");
 System.out.println(alpha);
 MyLinkedList<String> beta = new MyLinkedList<String>();
 beta.add("is");
 beta.add("java");
 beta.add("rocks");
 System.out.println(beta);
 alpha.addList(1, beta);
 System.out.println(alpha);
 }
}

The correct output would be something like:

OUTPUT:
[hello, is, java, rocks, world, this]

My program would not run, an error occurred in this line

alpha.addList(1, beta);

on the "beta" part, it says:

method addList in class MyLinkedList cannot be applied to given types; required: int,String found: int,MyLinkedList reason: actual argument MyLinkedList cannot be converted to String by method invocation conversion where E is a type-variable: E extends Object declared in class MyLinkedList

How would I fix my method so that I can use it correctly? Thanks in advance!!

• PearsonArtPhoto: Can you please add in vector definitions?
• Quetzalcoatl: I think you'll need your addList method to have the generic in there: public void <E> addList(int index, E e) {

Answer 1

It appears to me that your addList method signature is the problem. It should look like:

public void addList(int index, List<E> list)

Answer 2

You need to have a method for adding MyLinkedList<String>. Something like this would do

public void addList(int index, MyLinkedList<E> beta){
//Somehow loop through the MyLinkedList, and do this.
 add(index+i,beta(i));
}