X410: Linked Chain Find Node Before Value

Consider the following class definitions:

public class LinkedChain<T> {
    private Node<T> firstNode;
    private int numberOfEntries;

    public LinkedChain() {
        firstNode = null;
        numberOfEntries = 0;
    }// end default constructor


    public Node<T> getfirstNode() {
        return firstNode;
    }


    public int getNumberOfEntries() {
        return numberOfEntries;
    }



    public void push(T newEntry) {
        // TODO Auto-generated method stub
        firstNode = new Node<T>(newEntry, firstNode);
        numberOfEntries++;
    }
}

Where Node is defined as:

public class Node<T> {
     private T data; // Entry in bag
     private Node<T> next; // Link to next node

     public Node(T dataPortion) {
         this(dataPortion, null);
     } // end constructor


     public Node(T dataPortion, Node<T> nextNode) {
         data = dataPortion;
         next = nextNode;
     } // end constructor


     public T getData() {
         if (data != null) {
             return data;
         }
         return null;
     }


     public Node getNext() {
         return next;
     }


     public void setNext(Node<T> newNext) {
         next = newNext;
     }
}

Below, write a Linked Chain method that will return a reference to the node before the first node in the chain that equals to a given parameter (otherwise return null) - could do this with a look ahead or runner technique. Make sure to account for edge cases including if the linked chain is empty be sure to return null.

For example: Assuming you had a chain of

1-->2-->3-->4

and a parameter of 3, this method would need to return the node where data=2

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