Instance Variable v.s. Local Variable

[Jerry]

What is the difference between instance variable and local variable? Is
that true instance variables are shared among threads while local
variable is not shared?

public class Test
{
private String var1; // is this instance variable?
public int var2; // is this also instance variable?

private void method1()
{

String var3; // is this local variable?

}
}

Thanks a lot!

 

[KittyCreation]

Yes your comments are correct,
Instance variables are class level member variables. Local variables
are defined in a method/block.

Local variables are not shared amongst thread.

 

[KittyCreation]

Yes your comments are correct,
Instance variables are class level member variables. Local variables
are defined in a method/block.

Local variables are not shared amongst thread.

 

[Patricia Shanahan]

What is the difference between instance variable and local variable? Is
that true instance variables are shared among threads while local
variable is not shared?

public class Test
{
private String var1; // is this instance variable?
public int var2; // is this also instance variable?

private void method1()
{

String var3; // is this local variable?

}
}

Thanks a lot!

As well as being shared among threads, instance variables are shared
among method invocations. Changes in var1 or var2 will persist between
calls to method1, and to any other method that references them, while
var3's value is lost when method1 returns.

Patricia

 

[Thomas G. Marshall]

KittyCreation coughed up:

Yes your comments are correct,
Instance variables are class level member variables.

"class level member variables."

Perhaps is better phrased as

"object level member variables".

The terms "class" and "member" together (a conflict) might confuse someone
just learning OO.

 

[Roedy Green]

What is the difference between instance variable and local variable? Is
that true instance variables are shared among threads while local
variable is not shared?

see http://mindprod.com/jgloss/instance.html
http://mindprod.com/jgloss/local.html

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Complicit Bush-friendly media keeps mum. Rumsfeld confesses on video.
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