Re: How to assign a variable to Threads

See the docs of ThreadLocal:
http://java.sun.com/javase/6/docs/api/java/lang/ThreadLocal.html

The relevant portion of the page is reported below:

 >For example, the class below generates unique identifiers local to
each >thread. A thread's id is assigned the first time it invokes
 >UniqueThreadIdGenerator.getCurrentThreadId() and remains unchanged on
 >subsequent calls.
 >
 > import java.util.concurrent.atomic.AtomicInteger;
 >
 > public class UniqueThreadIdGenerator {
 >
 > private static final AtomicInteger uniqueId = new AtomicInteger(0);
 >
 > private static final ThreadLocal < Integer > uniqueNum =
 > new ThreadLocal < Integer > () {
 > @Override protected Integer initialValue() {
 > return uniqueId.getAndIncrement();
 > }
 > };
 >
 > public static int getCurrentThreadId() {
 > return uniqueId.get();

 > }
 > } // UniqueThreadIdGenerator
 >