Sword Point offer mergeorderedlist merge two sorted list

Title Description:

Enter two incrementally sorted lists, merge the two linked lists, and make the nodes in the new list still in ascending order

Ideas:
Recursively scan two arrays each time you point the next pointer to a smaller value for the current node in the linked list

public static ListNode mergeorderedlist (ListNode list1, ListNode list2) {
        if (List1 = = null) {
            return list2;
        }
        if (list2==null) {
            return list1;
        }
        ListNode node;
        if (List1.data < list2.data) {
            node = List1;
            Node.next = Mergeorderedlist (List1.next, List2);
        } else {
            node = list2;
            Node.next = Mergeorderedlist (List1, List2.next);
        }
        return node;
    }

public class Mergeorderedlisttest extends Basetest {private ListNode list1;

    Private ListNode List2;
        @Override @Before public void SetUp () throws Exception {Super.setup ();
        int[] data1 = new Int[]{1, 2, 3, 4, 5};
        int[] data2 = new int[]{2, 3, 4, 7, 8};
        List1 = Initlist (data1);
    List2 = Initlist (data2); } @Test public void Test () throws Exception {ListNode ListNode = mergeorderedlist.mergeorderedlist (list1
        , List2);
    Printlist (ListNode);
        } private ListNode Initlist (int[] data) {listnode[] node = new Listnode[data.length];
        for (int i = 0; i < node.length; i++) {Node[i] = new ListNode (Data[i]);
        } for (int i = 0; i < node.length-1; i++) {node[i].next = node[i + 1];
    } return node[0]; 
    } private void Printlist (ListNode node) {while (node! = null) {System.out.print (node.data+ "");        node = Node.next; }
    }
}

Output results

1 2 2 3 3 4 4 5 7 8