Core Java - Does Java support pass by reference. If yes/no- why?

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Does Java support pass by reference. If yes/no- why?

Total Answers and Comments: 7

Last Update: July 08, 2008 Asked by: sha_kr2001

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Submitted by: priyaranjan_BISWAL

Java does not support pass by reference. Java actually pass-by-value for all variables running within a single VM. pass-by-value means pass-by-variable-value and that means pass-by-copy-of the variable.

It makes no difference if you are passing primitive or reference variable, you always passing a copy of theÂ bits in the variable.

For example: if u are passing the variable with the value 3, you are passing theÂ copy of variable representing 3. If you are passing an object reference variable, you are passing the copy of the bits representing the reference to an object.

Above answer was rated as good by the following members:
interviewprep9, Naveenjavasun

January 03, 2008 01:30:27

priyaranjan_BISWAL

Member Since: August 2007 Contribution: 2

RE: Does Java support pass by reference. If yes/no- why?

Java does not support pass by reference. Java actually pass-by-value for all variables running within a single VM. pass-by-value means pass-by-variable-value and that means pass-by-copy-of the variable.

It makes no difference if you are passing primitive or reference variable, you always passing a copy of theÂ bits in the variable.

For example: if u are passing the variable with the value 3, you are passing theÂ copy of variable representing 3. If you are passing an object reference variable, you are passing the copy of the bits representing the reference to an object.

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January 09, 2008 00:37:27

keshavgopal.se

Member Since: December 2007 Contribution: 5

RE: Does Java support pass by reference. If yes/no- why?

Yes , java do support pass by reference. when ever we pass an object to the method it is call by reference only. The changes made for the state of the object inside the method call which is in other object will be reflected in the original object passed in ...

so this nothing but the pass by reference only.

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February 07, 2008 10:24:14

cricketfan04

Member Since: February 2008 Contribution: 2

RE: Does Java support pass by reference. If yes/no- why?

Java is purely pass-by-value only. The confusion is because when an object is passed, the objects value which in this case is the memory allocation is passed. Since the object received in the method has the same memory reference, this seems like it is passed by reference.

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February 11, 2008 06:02:51

sampra

Member Since: February 2008 Contribution: 279

RE: Does Java support pass by reference. If yes/no- why?

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June 08, 2008 07:27:25

ramesh124

Member Since: June 2008 Contribution: 2

RE: Does Java support pass by reference. If yes/no- why?

Java Supports pass by reference.
An object means, the variable which contains the starting location of its class.

When we pass the Object, it is internally getting the address of starting point.

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June 09, 2008 11:29:42

vegetto

Member Since: June 2008 Contribution: 10

RE: Does Java support pass by reference. If yes/no- why?

hi there,
the java technology supports a kind of pass by reference but this process applies only to the objects not the primitive data types ,i.e if you are familiar with c++ then you must be knowing that whatever changes you make in the the reference that are reflected back in call by reference, in the same way this happens in java but only in case of the objects.try a programme in which you instantiate a class and try to modify the primitive data type by calling it from the main method and kind of same process apply it to the case of objects ,you will find that only in the case of the objects the change occurs.for any further query please ask byeee

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July 08, 2008 03:38:53

Naveenjavasun

Member Since: July 2008 Contribution: 6

RE: Does Java support pass by reference. If yes/no- why?

Java always makes a copy of arguments & pass the copy.The called method has a local copy of data.If the the method changes the data it changes the copy, So original value is not changed.
             When we pass a prmitive like int ,the method gets its own int value.a copy of original.

       When we pass an Object, the value that is copied & set along a referance or pointer to the object.the method gets its own copy of pointer,it does not gets own copy of object.
    If method changes the copy of pointer to point to another object the original pointer is not effected.

   If the method changes the sme of the attribute of the object,it canges original object.

In short in java object are pass by referance & primitive types are passby value.

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