跳表是一種基于鏈表實現的數據結構，它能夠比傳統單鏈表更快地進行查找和更新操作。Java跳表通過利用隨機數生成器，將節點按照一定規則連接起來，使得查找時間復雜度為O(log n)。跳表在Java中有很多應用，比如Redis中的有序集合，以及一些集合操作的實現等。

public class SkipList {
private int levels;
private SkipListNode header;
private Random rand;
public SkipList(int maxLevels, SkipListNode header) {
this.levels = 1;
this.header = header;
this.rand = new Random();
}
public void insert(int value) {
int count = 0;
SkipListNode current = header;
SkipListNode[] update = new SkipListNode[levels];
for (int i = levels - 1; i >= 0; i--) {
while (current.getForward(i) != null && current.getForward(i).getValue()< value) {
current = current.getForward(i);
}
update[i] = current;
}
current = current.getForward(0);
if (current != null && current.getValue() == value) {
return;
}
int newLevels = 1;
while (rand.nextBoolean()) {
newLevels++;
}
if (newLevels >levels) {
for (int i = levels; i< newLevels; i++) {
update[i] = header;
}
levels = newLevels;
}
current = new SkipListNode(value, newLevels);
for (int i = 0; i< newLevels; i++) {
current.setForward(i, update[i].getForward(i));
update[i].setForward(i, current);
}
}
public boolean search(int value) {
SkipListNode current = header;
for (int i = levels - 1; i >= 0; i--) {
while (current.getForward(i) != null && current.getForward(i).getValue()< value) {
current = current.getForward(i);
}
}
current = current.getForward(0);
return (current != null && current.getValue() == value);
}
public void delete(int value) {
SkipListNode current = header;
SkipListNode[] update = new SkipListNode[levels];
for (int i = levels - 1; i >= 0; i--) {
while (current.getForward(i) != null && current.getForward(i).getValue()< value) {
current = current.getForward(i);
}
update[i] = current;
}
current = current.getForward(0);
if (current != null && current.getValue() == value) {
for (int i = 0; i< levels; i++) {
if (update[i].getForward(i) != current) {
break;
}
update[i].setForward(i, current.getForward(i));
}
}
}
}

上述代碼是一個簡單的Java跳表實現。它通過維護每個節點的前向指針數組，和隨機數生成器來實現節點的層數變化和排序。除了基本的插入、刪除、查找操作之外，還可以實現一些集合操作，比如求交集、并集等，同時，跳表的平衡性和可擴展性使得它有很好的應用前景。