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From: Eric Sosman <esosman@comcast-dot-net.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: JDK 9 strings very slow
Date: Mon, 27 Aug 2018 13:32:34 -0400
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On 8/27/2018 1:17 PM, j4n bur53 wrote:
> But I still see some problems with this approach,
> like for example. Did Java amend equals, and like
> do a check alfa.value==beta.value ?
> 
> I only find in JDK 8:
> 
>          if (this == anObject) {
>              return true;
>          }
>          if (anObject instanceof String) {
>              String anotherString = (String)anObject;
>              int n = value.length;
>              if (n == anotherString.value.length) {
>                  char v1[] = value;
>                  char v2[] = anotherString.value;
>                  int i = 0;
>                  while (n-- != 0) {
>                      if (v1[i] != v2[i])
>                          return false;
>                      i++;
>                  }
>                  return true;
>              }
>          }
>          return false;

     This Java source code may be somewhat misleading.  I'm not
certain, but here and there in the discussion-and-issue pages
you'll find references to "the HotSpot VM's intrinsic string
operations" -- which suggests (to me) that the JVM might have
its own internal native implementations of some String methods.
The visible Java code might not execute at all, or might execute
only on JVM's that don't "internal-ize" quite so aggressively.

     Permit me to ask: Why are the internals of the JVM's String
handling of such interest to you?  Is it just laudable curiosity,
or are you confronting a difficulty of some kind?

-- 
esosman@comcast-dot-net.invalid
Eight hundred seventy-seven days to go.