Is Object constructor called when creating an array in Java?

Question

In Java, an array IS AN Object. My question is... is an Object constructor called when new arrays is being created? We would like to use this fact to instrument Object constructor with some extra bytecode which checks length of array being constructed. Would that work?

Answer 1

As far as the Java Language Specification is concerned, although both use the new keyword, Class Instance Creation Expressions and Array Creation Expressions are different forms of expression, each with its own rules. The description of Array Creation Expressions does not mention calling a constructor.

Answer 2

Per the JVM spec: "Arrays are created and manipulated using a distinct set of instructions." So, while arrays are instances of Objects, they aren't initialized the same way that other objects are (which you can see if you scroll up from that link anchor).

Answer 3

I don't think so because you can not derive a native array to overridethe constructor

Answer 4

You can use byte code manipulation to place the check where ever a new array is created.

Answer 5

Nope. I found this on the AspectJ mailing list: http://dev.eclipse.org/mhonarc/lists/aspectj-users/msg02975.html.

You probably ask about arrays for a reason, but if you can, why not switch to the collection classes. That will give you lots of opportunity to intercept and do validations.