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autoboxing

Java wrapping a primitive in its wrapper object automatically, as when list.add(42) stores an Integer.

An implicit Integer.valueOf (or matching valueOf) call where a reference is required; values from -128 to 127 share cached objects.

Examples

  • List<Integer> xs = new ArrayList<>(); xs.add(5); boxes the int 5 into an Integer.

See also

unboxing wrapper class
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