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POJava Linked List - add method
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copied!<p>Data structures class, implementing a singly linked-list with head, tail and current nodes. Having trouble with a method, could use a nudge in the right direction.</p> <p>From the assignment, write the method:</p> <p>add( item ) : adds the item (String) after the current node in the list and sets the current pointer to refer to the new node.</p> <p>My attempt:</p> <pre><code>public void add(String item) { if(curr != null) { Node newNode = new Node(item, curr.next); curr.next = newNode; curr = newNode; } else { head = tail = new Node(item, null); curr = head; } } </code></pre> <p>My add method only seems to work when I'm adding items to the middle of the list, not on either end. If I use it to add a few items and then print the list, only the first one I added will be on the list, while my prepend and append methods have tested just fine.</p> <p>Is there any glaring issue with my code? I feel like I'm missing something obvious.</p> <p>All:</p> <pre><code>public class LinkedList { Node head = null; /* Head of the list */ Node tail = null; /* Tail of the list */ Node curr = null; /* Current node in the list */ public void prepend(String item) { if (head == null) { head = tail = new Node(item, null); curr = head; } else { head = new Node(item, head); curr = head; } } public void append(String item) { if (head == null) { head = tail = new Node(item, null); curr = tail; } else { tail.next = new Node(item, null); tail = tail.next; curr = tail; } } public void add(String item) { if (curr != null) { Node newNode = new Node(item, curr.next); curr.next = newNode; curr = newNode; } else { head = tail = new Node(item, null); curr = head; } } public void delete() { if (curr.next == null) { Node temp = head; while (temp.next != curr) { System.out.println(temp.item); temp = temp.next; } temp.next = null; curr = head; } } public void find(String item) { Node temp = new Node(curr.item, curr.next); if (item.equals(temp.item)) curr = temp; else { temp = temp.next; while (temp.next != null && temp != curr) { if (item.equals(temp.item)) curr = temp; } } } public String get() { if (curr != null) return curr.item; else return ""; } public boolean next() { if (curr != tail) { curr = curr.next; return true; } else return false; } public void start() { curr = head; } public void end() { curr = tail; } public boolean empty() { if (head == null) return true; else return false; } } </code></pre> <p><code>Node</code> class:</p> <pre><code>class Node { Node next; String item; Node(String item, Node next) { this.next = next; this.item = item; } } </code></pre>

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