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The Java Developers Almanac 1.4Order this book from Amazon. |
e346. Storing Primitive Types in a CollectionCollections can only store objects, not primitive types likeint
and double . Primitive types must be placed in a wrapper
object before they can be placed in a collection. This example
demonstrates the storing of int values in a Map .
See also: e58 Wrapping a Primitive Type in a Wrapper Object. // Create map Map map = new HashMap(); // Create int wrapper object Integer refInt = new Integer(123); // Store int in map map.put("key", refInt); // Get int value from map refInt = (Integer)map.get("key"); // Get the integer value from wrapper object int i = refInt.intValue();
e343. Implementing a Stack e344. Implementing a Least-Recently-Used (LRU) Cache e345. Listing the Elements of a Collection e347. Creating a Copy of a Collection e348. Making a Collection Read-Only
© 2002 Addison-Wesley. |