将List改造成线程安全的

package cn.edu.bjfu.main;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;

public class MainTest {

	public static void main(String[] args) {
		
		List<Integer> list = new ArrayList<>();
		
		List<Integer> sycList = new MyList<>(list);
		
		// 线程A将0-1000添加到list
	    new Thread(new Runnable() {
	        public void run() {
	            for (int i = 0; i < 1000 ; i++) {
	            	sycList.add(i);

	                try {
	                    Thread.sleep(1);
	                } catch (InterruptedException e) {
	                    e.printStackTrace();
	                }
	            }
	        }
	    }).start();

	    // 线程B将1000-2000添加到列表
	    new Thread(new Runnable() {
	        public void run() {
	            for (int i = 1000; i < 2000 ; i++) {
	            	sycList.add(i);

	                try {
	                    Thread.sleep(1);
	                } catch (InterruptedException e) {
	                    e.printStackTrace();
	                }
	            }
	        }
	    }).start();

		
	    try {
			Thread.sleep(2000);
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		//sycList.add(1);
		//sycList.add(2);
		
		for (Integer s : sycList) {
			System.out.println(s);
		}
		
		
	}

}
class MyList<T> implements List<T> {
	
	private static final Object lock = new Object();//定义一个锁
	
	private List<T> list;
	
	public MyList(List<T> list) {
		this.list = list;
	}

	@Override
	public int size() {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public boolean isEmpty() {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean contains(Object o) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public Iterator<T> iterator() {
		synchronized (lock) {
			return list.iterator();
		}
		
	}

	@Override
	public Object[] toArray() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public <T> T[] toArray(T[] a) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public boolean add(T e) {
		synchronized (lock) {
			return list.add(e);
		}
	}

	@Override
	public boolean remove(Object o) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean containsAll(Collection<?> c) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean addAll(Collection<? extends T> c) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean addAll(int index, Collection<? extends T> c) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean removeAll(Collection<?> c) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public boolean retainAll(Collection<?> c) {
		// TODO Auto-generated method stub
		return false;
	}

	@Override
	public void clear() {
		// TODO Auto-generated method stub
		
	}

	@Override
	public T get(int index) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public T set(int index, T element) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public void add(int index, T element) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public T remove(int index) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public int indexOf(Object o) {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public int lastIndexOf(Object o) {
		// TODO Auto-generated method stub
		return 0;
	}

	@Override
	public ListIterator<T> listIterator() {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public ListIterator<T> listIterator(int index) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public List<T> subList(int fromIndex, int toIndex) {
		// TODO Auto-generated method stub
		return null;
	}
	
}