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From: =?UTF-8?Q?Arne_Vajh=c3=b8j?= <arne@vajhoej.dk>
Newsgroups: comp.lang.java.programmer
Subject: Re: Never using booleans as parameters
Date: Sun, 22 Nov 2015 14:03:55 -0500
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On 11/20/2015 12:44 PM, leif.roar@dimnakorr.com wrote:
> Cecil Westerhof <Cecil@decebal.nl> wrote:
>> Often is said that you should never use booleans as parameters. But I
>> have a function compareObjects that takes two objects and a boolean
>> that signifies if the function is verbose. (Sends logging.)
>>
>> I could of-course define compareObjects and compareObjectsVerbose and
>> instead of writing:
>>     compareObjects(a, b, useVerbose);
>
> If this is a private method, that's perfectly fine, but if it's a method
> that's part of an API, I'd probably want to do it like this:
>
> Enum LoggingVerbosity {
>    NONE,
>    VERBOSE;
> }
>
>
> boolean compareObjects( T a, T b ) {
>    return compareObjects( a, b, LoggingVerbosity.NONE );
> }
>
> boolean compareObjects( T a, T b, LoggingVerbosity verbosity ) {
>    switch( verbosity ) {
>      case NONE: ...
>      case VERBOSE: ...
>      default throw new ProgrammingError( "Unhandled LoggingVerbosity type " + verbosity
>          + " encountered in switch statement. This should not happen." );
>    }
> }

That is a very valid point.

boolean only have two value's so if the number of values could increase
later then boolean should not be used and enum is the type safe way of
doing that compared to int constants.

Arne