public class MyThreadLocal<T> {

    private Map<Thread, T> map = Collections.synchronizedMap(new HashMap<Thread, T>());

    public void set(T newValue) {

        map.put(Thread.currentThread(), newValue);

    }

    public T get() {

        return map.get(Thread.currentThread());

    }

    public void remove() {

        map.remove(Thread.currentThread());

    }

}

package com.lxc.tet;

import java.util.Map;

import java.util.concurrent.ConcurrentHashMap;

public class MyThreadLocal<T> {

    private Map<Thread,T> map = new ConcurrentHashMap<Thread, T>();

    protected T initialValue(){

        return null;

    }

    public void set(T value){

        map.put(Thread.currentThread(), value);

    }

    public T get(){

        T result = null;

        result = map.get(Thread.currentThread());

        if(result==null && !map.containsKey(Thread.currentThread())){

            result=initialValue();

            set(result);

        }

        return result;

    }

    public void remove(){

        map.remove(Thread.currentThread());

    }

}