As i know that Object is the super most class of all classes in java. But, below code i am not able to understand. please help me out.
Object c = new long[4];
Object d = new int[4];
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Konstantin Yovkov
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Java Professional
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Actually, i know that int a[] = new int[10]; is possible. how above statements are compiling... – Java Professional Jun 30 '13 at 19:29
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2Because an `array of primitives` is an object. – Konstantin Yovkov Jun 30 '13 at 19:30
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@kocko you are right, just want to add that not only of primitives, every array in Java is Object. – Pshemo Jun 30 '13 at 19:31
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In the Java programming language, arrays are objects (§4.3.1), are dynamically created, and may be assigned to variables of type Object (§4.3.2). All methods of class Object may be invoked on an array
From the Java Language Specification.
Konstantin Yovkov
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Adam Siemion
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As written, this should give you an error because you are re-declaring a variable named c. However, the following is perfectly valid:
Object c = new long[4];
c = new int[4];
This works because, as you say, Object is the superclass of all non-primitive types in Java.
ChaseMedallion
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Note; after kocko's edit the redeclaring c issue no longer exists – Richard Tingle Jun 30 '13 at 20:06
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Object is the super class of arrays in Java (mentioning just arrays because the question demands so).
So when you assign a long array to object it is internally type casted to Object.
Similarly for int. So in the end in both statements the variable on the right is an Object. However, you cannot have Object c = in both the lines.
JHS
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`Object` is the super class of every class, array, interface and enum in Java, not of "everything in Java". :) – Konstantin Yovkov Jun 30 '13 at 19:32
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Yeah. Yeah. I know. Was in a hurry. ;) You can edit. Its difficult to do it from the phone. – JHS Jun 30 '13 at 19:34