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Re: What's the best way to make a cross string set?

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On 7/31/2017 8:24 AM, Eric Douglas wrote:
> You're saying declaring a variable as a List is more efficient even
> if you know it's going to be instantiated as ArrayList?  I've always
> tried to avoid that because it's one more line in the import section,
> and I never use * imports because that just sounds confusing at best
> messy at worst when you get into the same class names in multiple
> packages.

List<X> lst = new ArrayList<X>();

is often considered better than:

ArrayList<X> lst = new ArrayList<X>();

The import cost nothing.

And by using the interface List<> then it is possible to change
the actual type later to a different List<> implementation without
worrying about code using methods only available in ArrayList<>.

Reference:

Effective Java 2nd Ed / Bloch Item 52.

The question comes up frequently.

SO examples:

https://stackoverflow.com/questions/2279030/type-list-vs-type-arraylist-in-java
https://stackoverflow.com/questions/9852831/polymorphism-why-use-list-list-new-arraylist-instead-of-arraylist-list-n
https://stackoverflow.com/questions/18329311/reason-for-list-list-new-arraylist

Arne

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Thread

What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 12:12 -0700
  Re: What's the best way to make a cross string set? Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2017-07-27 14:38 -0500
    Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 12:49 -0700
  Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-27 15:49 -0400
    Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 12:55 -0700
    Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 13:22 -0700
      Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 13:30 -0700
      Re: What's the best way to make a cross string set? Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2017-07-27 15:34 -0500
      Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-27 18:27 -0400
        Re: What's the best way to make a cross string set? lewbloch@gmail.com - 2017-07-28 18:51 -0700
    Re: What's the best way to make a cross string set? v_borchert@despammed.com (Volker Borchert) - 2017-07-29 06:03 +0000
  Re: What's the best way to make a cross string set? v_borchert@despammed.com (Volker Borchert) - 2017-07-28 18:19 +0000
    Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-28 13:28 -0700
      Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-28 17:20 -0400
        Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-31 05:24 -0700
          Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-31 12:01 -0400
            Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-31 10:58 -0700
          Re: What's the best way to make a cross string set? Sebastian <nowhere@nirvana.org> - 2017-07-31 18:13 +0200
          Re: What's the best way to make a cross string set? lewbloch@gmail.com - 2017-07-31 09:24 -0700
          Re: What's the best way to make a cross string set? Arne Vajhøj <arne@vajhoej.dk> - 2017-07-31 19:24 -0400
        Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-01 06:36 -0700
          Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-01 10:58 -0400
            Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-01 08:09 -0700
              Re: What's the best way to make a cross string set? lewbloch@gmail.com - 2017-08-01 09:39 -0700
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-01 10:18 -0700
                Re: What's the best way to make a cross string set? Andreas Leitgeb <avl@logic.at> - 2017-08-02 09:22 +0000
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-02 05:13 -0700
                Re: What's the best way to make a cross string set? Andreas Leitgeb <avl@logic.at> - 2017-08-03 14:33 +0000
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-03 08:51 -0700
                Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-03 12:20 -0400
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-03 10:15 -0700
                Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-03 13:42 -0400
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-03 11:17 -0700
                Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-05 16:08 -0400
                Re: What's the best way to make a cross string set? Martin Gregorie <martin@address-in-sig.invalid> - 2017-08-05 20:31 +0000
                Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-05 17:25 -0400
                Re: What's the best way to make a cross string set? Martin Gregorie <martin@address-in-sig.invalid> - 2017-08-05 22:11 +0000
                Re: What's the best way to make a cross string set? Sebastian <nowhere@nirvana.org> - 2017-08-06 18:13 +0200
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-02 12:56 -0700
  Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-29 16:55 -0400
  Re: What's the best way to make a cross string set? Sebastian <nowhere@nirvana.org> - 2017-07-29 23:56 +0200

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