Re: API design

From:

Daniel Pitts <newsgroup.spamfilter@virtualinfinity.net>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 24 Jun 2009 12:20:11 -0700

Message-ID:

<O%u0m.36323$Ig.19375@newsfe14.iad>

Stefan Ram wrote:

  I assume that one wants to design an API with the option to
  open a FileOutputStream for /append mode/. There are several
  possibilities, and one can compare their readability,
  extendability (fitness for later API extensions), usability
  and other software quality factors. (feel free to comment):

==

  new FileOutputStream( "path", "a" );

Meh.

==

new FileOutputStream( "path", "append" );

Eh, verbose is good, string is bad.

==

new FileOutputStream( "path", true );

Ew, no.

==

new FileOutputStream( "path", FileOutputStream.APPEND_MODE );

Sure, if that is an enum value.

==

new FileOutputStream( "path", FileAccessMode.APPEND_MODE );

Sure, if that is an enum value.

==

new FileOutputStream( path, new AppendMode() );

/* here, ?AppendMode? might be a subtype of another type ?FileAccessMode? */

No, because a user would then be able to create a new FileAccessMode
class that doesn't make sense to FileOutputStream.

==

new FileOutputStream( path, new FileAccessMode( "append" ));

Only slightly better than (path, "append").

==

new AppendFileOutputStream( path );

No.

/* here, ?AppendFileOutputStream? might be a subtype of ?FileOutputStream? */

==

Possibly, I have missed others possibilities to design this.

Another possibility: FileOutputStream.openForAppend(path);
Although, I still would prefer FileAccessMode.APPEND_MODE over all the
others for this particular case.

--
Daniel Pitts' Tech Blog: <http://virtualinfinity.net/wordpress/>

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