Integer 包装类型

//Integer包装类


class MemoryCell
{
	//public methods
	public Object read()
	{
		return storedValue;
	}
	public void write(Object x)
	{
		storedValue = x;
	}
	//private internal data representation
	private Object storedValue;
}



public class WrapperDemo
{
	public static void main(String[] args)
	{
		MemoryCell m = new MemoryCell();
		m.write(new Integer(21));
		Integer wrapperValue = (Integer)m.read();
		int val = wrapperValue.intValue();
		System.out.println("contents are:"+val);
	}
}