?? e346. storing primitive types in a collection.txt
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Collections can only store objects, not primitive types like int 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();
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