The Java Developers Almanac 1.4

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e347. Creating a Copy of a Collection

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);

Related Examples

e342. Implementing a Queue
e343. Implementing a Stack
e344. Implementing a Least-Recently-Used (LRU) Cache
e345. Listing the Elements of a Collection
e346. Storing Primitive Types in a Collection
e348. Making a Collection Read-Only

See also: Arrays Bits Dates Hash Tables Lists Property Files Sets Sorted Collections Time Timers

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