DoubleNode.java

DoubleNode.java

package edu.cmu.cs771.hw1;

/**
 * The class DoubleNode holds two pointers and a character. It is used to represent a single node on a double linked list. 
 * @author songluo
 *
 */
public class DoubleNode {
        private DoubleNode prev;
        private DoubleNode next;
        private char c;
        
        /**
         * Constructor with no arguments.
         */
        public DoubleNode(){
                this( null, '\0', null );
        }
        
        /**
         * Constructor with a character 
         * @param ch is a character for this node.
         */
        public DoubleNode(char ch){
                this(null, ch, null);
        }
        
        /**
         * Constructor with three arguments
         * @param p is a pointer to a previous node.
         * @param ch is a character for this node.
         * @param n is a pointer to a next node.
         */
        public DoubleNode(DoubleNode p, char ch, DoubleNode n){
                prev = p;
                next = n;
                c = ch;
        }
        
        /**
         * @return c a character for this node.
         */
        public char getC(){
                return c;
        }
        
        /**
         * @return a pointer to the next node or null if none exists
         */
        public DoubleNode getNext(){
                return next;
        }
        
        /**
         * @return a pointer to the previous node or null if none exists
         */
        public DoubleNode getPrev(){
                return prev;
        }
        
        /**
         * @param ch is assigned to this node
         */
        public void setC(char ch){
                c = ch;
        }
        
        /**
         * @param n
         */
        public void setNext(DoubleNode n){
                next = n;
        }

        /**
         * @param p
         */
        public void setPrev(DoubleNode p){
                prev = p;
        }
        
        /** 
         * @see java.lang.Object#toString()
         */
        public String toString(){
                return Character.toString(c);
        }
        
        /**
         * Test driver for DoubleNode 
         * @param args
         */
        public static void main(String args[]){
                System.out.println("hello");
        }
}