How to launch threads from a thread

Hi, I am developing an application to spider web pages and I have basically 3 classes: SpiderController, SpiderPool and Spider.
The idea is that the SpiderController creates SpiderPools each spider pool with some proxy configuration and a list of pages to spider, and finally the Spider is created inside the spider pool and takes one of the pages to spider.
I want to launch each SpiderPool in one thread and then in each SpiderPool I also want to launch one Spider with a page in one thread.
At the moment I have this code:
//Class spider Controller
public class SpiderController{
public executePageSpider{
//list of all the pages to spider
Vector<String> pageList = task.pageList();
//Split the list in two parts one for each spiderpool
     Vector<String> pageListGroup1 = new Vector<String>(pageList.
               subList(0, pageList.size()/2));
     Vector<String> pageListGroup2 = new Vector<String> (pageList.
               subList((pageList.size()/2)+1,pageList.size()));
     //Creating one spider pool with each part
     //Each spiderpool has a different proxy configuration
     SpiderPool spool1 = new SpiderPool(proxyList.get(0),pageListGroup1);
     SpiderPool spool2 = new SpiderPool(proxyList.get(1),pageListGroup2);
     spool1.run();
     spool2.run();
//Class SpiderPool
public class SpiderPool extends Thread implements Constants{
private Proxy proxy;
private Vector<String> pageList
public void run(){
System.out.println("-------------- Runing Spider pool --------");
for(String page : pageList){
Spider sp = new Spider(page);
     sp.run();
//class Spider
public class Spider extends Thread{
public void run(){
//Code to get the page code and wite it into file
The problem that I have is that the spiderpools are not launched as a Thread. The second one (spiderpool2) doesn't start until the first spiderpool finish. By the way the Spiders are in different threads as I can see debugging.
I dont know if I have something wrong in my code...
Anybody can help me about how can I run each SpiderPool in a different thread and from this thread launch the spiders in threads?
Thanks

spool1.run();
spool2.run();
spool1.start();
spool2.start();

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