Re: "some text".equals(someString)

[Arnaud Vandyck <arnaud.vandyck@ulg.ac.be>]

Francois BOTTIN <frbottin@yahoo.fr> wrote:

>  --- "E.L. Willighagen" <egonw@sci.kun.nl> wrote: 
> > 
> > Hi all,
> > 
> > can anyone tell me the difference (performance etc) between:
> > 
> > 1. String someString = "text"
> >    if ("some text".equals(someString)) {};
> > 
> > and
> > 
> > 2. String someString = "text"
> >    if (someString.equals("some text")) {};
> > 
> 
> I don't know if there's a difference in performance (and it will
> certainly depend of the JVM implementation).

I do not think there is a difference.

> Personnaly I use the first alternative as it permits null values for
> someString without throwing a NullPointerException. 

So do I.

> It's  also possible  to have  someString  that's not  declared as  a
> String   (you  don't   need  to   cast   it,  and   hence  avoid   a
> ClassCastException).

Well,  .equals(Object) is  an Object  method, so  you'll never  have a
casting probleme.  Even for a String,  myString.equals(Object) and NOT
myString.equals(String)

java.lang
Class String

java.lang.Object
  |
  +--java.lang.String
+---------------+----------------------------------------------------+
|       boolean | equals(Object anObject)                            |
|               |           Compares this string to the specified    |
|               |           object.                                  |
+---------------+----------------------------------------------------+

-- Arnaud, STE-Formations Informatiques, fapse, ULg, .BE