Confused by how "pass in by value" works

Question

I'm new to Java and am confused by how "pass in by value" works.

int[] a;

public Constructor(int[] anArrayOfInt){ 
    a = anArrayOfInt;
}

does variable a point to the object passed into the constructor? Do changes to variable a reflect in the object that is passed into the constructor?

"*Do changes to variable a reflect in the object that is passed into the constructor?*" - Should be easy to check that yourself — OneCricketeer, Jun 25 '16 at 05:02

score 2 · Accepted Answer · edited Jun 25 '16 at 05:04

2

Does variable a points to the object passed into the Constructor?

Answer is yes.

Does changes to variable a reflects in the object that is passed into the Constructor?

Answer is yes.

Because in java, parameter is passed by value. When you pass a object to method, actual, you are passing a reference of object.

edited Jun 25 '16 at 05:04

OneCricketeer

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answered Jun 25 '16 at 05:02

ThiepLV

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this is where I'm a bit confused, if java pass in by value, shouldn't it create a copy of the passed in object (which is distinct to the original passed in object) and assign variable 'a' to the copied object? apology for asking a simple question like this, but i'm so confused about it – Thor Jun 25 '16 at 05:07
2

@TonyStark No, it makes a copy of the reference, or in the case of primitives (`int`, `long`, `boolean`, etc) a copy of the value. – Jim Garrison Jun 25 '16 at 05:38

Confused by how "pass in by value" works

1 Answers1