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Re: Java String.hashCode-Algorithmus

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>> Ist der Algorithmus von hashCode für String irgenddwo dokumentiert?

> Was spricht denn gegen einen Blick in den Quellcode?
> 
>      /**
>       * Returns a hash code for this string. The hash code for a
>       * {@code String} object is computed as
>       * <blockquote><pre>
>       * s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1]
>       * </pre></blockquote>
>       * using {@code int} arithmetic, where {@code s[i]} is the
>       * <i>i</i>th character of the string, {@code n} is the length of
>       * the string, and {@code ^} indicates exponentiation.
>       * (The hash value of the empty string is zero.)
>       *
>       * @return  a hash code value for this object.
>       */
>      public int hashCode() {
>          int h = hash;
>          if (h == 0 && value.length > 0) {
>              char val[] = value;
> 
>              for (int i = 0; i < value.length; i++) {
>                  h = 31 * h + val[i];
>              }
>              hash = h;
>          }
>          return h;
>      }

Das ist aber was anderes als was die Doku sagt:
https://docs.oracle.com/javase/9/docs/api/java/lang/String.html#hashCode--

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Java String.hashCode-Algorithmus Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-26 10:09 +0200
  Re: Java String.hashCode-Algorithmus Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-26 10:11 +0200
  Re: Java String.hashCode-Algorithmus Michael Paap <feunews@mpaap.de> - 2019-08-26 10:42 +0200
    Re: Java String.hashCode-Algorithmus Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-26 11:01 +0200
      Re: Java String.hashCode-Algorithmus Michael Paap <feunews@mpaap.de> - 2019-08-26 11:05 +0200
        Re: Java String.hashCode-Algorithmus Michael Paap <feunews@mpaap.de> - 2019-08-26 11:09 +0200
          Re: Java String.hashCode-Algorithmus Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-26 11:33 +0200
            Re: Java String.hashCode-Algorithmus Patrick Roemer <sangamon@netcologne.de> - 2019-08-26 11:53 +0200
            Re: Java String.hashCode-Algorithmus Michael Paap <feunews@mpaap.de> - 2019-08-26 11:46 +0200
              Re: Java String.hashCode-Algorithmus Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-26 13:05 +0200
                Re: Java String.hashCode-Algorithmus Joerg Meier <joergmmeier@arcor.de> - 2019-08-26 13:27 +0200
                Re: Java String.hashCode-Algorithmus Michael Paap <feunews@mpaap.de> - 2019-08-26 14:17 +0200
                Re: Java String.hashCode-Algorithmus Joerg Meier <joergmmeier@arcor.de> - 2019-08-26 17:23 +0200
                Re: Java String.hashCode-Algorithmus Michael Paap <feunews@mpaap.de> - 2019-08-26 14:14 +0200
        Re: Java String.hashCode-Algorithmus Claus Reibenstein <4spamersonly@kabelmail.de> - 2019-08-26 13:10 +0200
  Re: Java String.hashCode-Algorithmus Wanja Gayk <brixomatic@yahoo.com> - 2019-09-20 16:57 +0200

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