这里面包含了一百多个JAVA源文件

				These examples create a shallow copy of a collection. That is, the new collection contains references to same objects as the source collection; the objects are not cloned. 
				    List stuff = Arrays.asList(new String[]{"a", "b"});
				    
				    // Make a copy of a list
				    List list = new ArrayList(stuff);
				    List list2 = new LinkedList(list);
				    
				    // Make a copy of a set
				    Set set = new HashSet(stuff);
				    Set set2 = new TreeSet(set);
				    
				    // Make a copy of a map
				    Map map = new HashMap();
				    // Add key/value pairs ...
				    Map map2 = new TreeMap(map);