java中链表实现

package linklist;

public class Node {
	public int iData;
	public double dData;
	public Node next;

	public Node(int iData, double dData) {
		this.iData = iData;
		this.dData = dData;
	}

	public void displayLink() {
		System.out.println("{" + iData + "," + dData + "}");
	}
}


package linklist;

public class LinkList {
	private Node head;

	public LinkList() {
		head = null;
	}

	public void insertFirst(int iData, double dData) {
		Node newNode = new Node(iData, dData);
		newNode.next = head;
		head = newNode;
	}

	public Node find(int key) {
		Node currentNode = head;
		while (currentNode.iData != key) {
			if (currentNode.next == null)
				return null;
			else
				currentNode = currentNode.next;
		}
		return currentNode;
	}

	public Node delete(int key) {
		Node currentNode = head;
		Node previousNode = head;
		while (currentNode.iData != key) {
			if (currentNode.next == null)
				return null;
			else {
				previousNode = currentNode;
				currentNode = currentNode.next;
			}
		}
		if (currentNode == head) {
			head = head.next;
		} else {
			previousNode.next = currentNode.next;
		}
		return currentNode;
	}

	public void displayList() {
		System.out.println("List(first-->last):");
		Node currentNode = head;
		while (currentNode != null) {
			currentNode.displayLink();
			currentNode = currentNode.next;
		}
		System.out.println();
	}

	public static void main(String[] args) {
		LinkList linkList = new LinkList();
		linkList.insertFirst(1, 12);
		linkList.insertFirst(2, 234);
		linkList.insertFirst(3, 11234);
		linkList.insertFirst(4, 2342);
		linkList.insertFirst(5, 2342);
		linkList.insertFirst(6, 234);
		linkList.insertFirst(7, 3452);
		linkList.displayList();
		Node find = linkList.find(4);
		if (find != null)
			System.out.println("The dData of the " + find.iData + " is "
					+ find.dData);
		else
			System.out.println("There is no " + find.iData);
		Node delete = linkList.delete(4);
		if (delete != null) {
			System.out.println("The dData of the " + delete.iData + " is "
					+ delete.dData);
		} else {
			System.out.println("There is no " + delete.iData);
		}
		linkList.displayList();
	}
}