Combining linked lists.

[syle_q]

I wrote a method that combines two linked lists that are populated with "textbook" objects. Both of the list are sorted alphabetically sorted prior to joining and the final list after joining should also be alphabetically sorted. I wrote a method with what I thought might work but nothing happens, can anyone tell me why nothing is done from this code.

***neither of the lists are empty***

    public void join(DLinkedList other) {

        Node tempOne = head;
        Node tempTwo = other.head;
        
        if(this.isEmpty()== true || other.isEmpty() == true){
            System.out.println("Need two populated lists to perform join operation");
            return;
        }
        
        while( tempOne != null && tempTwo != null){
            
            if(tempTwo.compareTo(head) < 0){
                Node insert = tempTwo;
                insertHead(insert);
                tempTwo = tempTwo.fpointer;
            }
            
            if(tail.compareTo(tempTwo) < 0){
                Node insert = tempTwo;
                insertTail(insert);
                tempTwo = tempTwo.fpointer;
            }
            
            
            if(tempOne.compareTo(tempTwo) < 0){
                tempOne = tempOne.fpointer;
                
                if(tempOne.compareTo(tempTwo) > 0){
                    Node insert = tempTwo;
                    insert.fpointer = tempOne;
                    insert.bpointer = tempOne.bpointer;
                    tempOne.bpointer.fpointer = insert;
                    tempOne.bpointer = insert;
                    tempTwo = tempTwo.fpointer;
                    
                }
            }
        }
       
    }

[Norm]

Can you make a small, complete program that compiles, executes and shows the problem?

Try debugging your code by adding lots of println statements that show where the execution flow goes and what the values of the variables are as the code executes and as the variables values are changed and used.