手写LinkList

package cn.oumashu.collection;

public class Node {
private Node previous;
private Object obj;
private Node next;

public Node() {
super();
}

public Node(Node previous, Object obj, Node next) {
super();
this.previous = previous;
this.obj = obj;
this.next = next;
}

public Node getPrevious() {
return previous;
}

public void setPrevious(Node previous) {
this.previous = previous;
}

public Object getObj() {
return obj;
}

public void setObj(Object obj) {
this.obj = obj;
}

public Node getNext() {
return next;
}

public void setNext(Node next) {
this.next = next;
}

}

package cn.oumashu.collection;

public class MyLinkList {
private Node first;
private Node last;
private int size;

public MyLinkList() {
super();
}

public int size() {
return size;
}

private void rangeCheck(int index) {
if(index<0||index>=size) {
try {
throw new Exception();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

public Node node(int index) {
Node temp = null;
if(first!=null) {
temp = first;
for(int i=0;i<index;i++) {
temp = temp.getNext();
}
}
return temp;
}

public void add(Object obj) {
Node temp = new Node();
temp.setObj(obj);
if(first==null) {
temp.setPrevious(null);
temp.setNext(null);
first = temp;
last = temp;
}else {
temp.setPrevious(last);
temp.setNext(null);
last.setNext(temp);
last = temp;
}
size++;
}

public void add(int index, Object obj) {
rangeCheck(index);
Node temp = node(index);
if(temp!=null) {
Node newNode = new Node();
newNode.setObj(obj);
Node pretemp = new Node();
pretemp = (temp.getPrevious());
newNode.setPrevious(pretemp);
newNode.setNext(temp);
pretemp.setNext(newNode);
temp.setPrevious(newNode);
}
size++;
}

public Object get(int index) {
rangeCheck(index);
Node temp = node(index);
if(temp!=null) {
return temp.getObj();
}
return null;
}

public void remove(int index) {
rangeCheck(index);
Node temp = node(index);
if(temp!=null) {
Node pretemp = temp.getPrevious();
Node nextemp = temp.getNext();
pretemp.setNext(nextemp);
nextemp.setPrevious(pretemp);
}
size--;
}

public static void main(String[] args) {
MyLinkList list = new MyLinkList();
list.add("a");
list.add("b");
System.out.println(list.get(1));
list.add(1, "c");
System.out.println(list.get(1));
list.remove(1);
System.out.println(list.get(1));
System.out.println(list.size());
}
}