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Re: Good pattern for realizing the out-param capability in Java?

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Low level granularity, use case agnostic approach:

     Value Holder Pattern:
     http://stackoverflow.com/questions/1403921/output-parameters-in-java
     A value holder for each out, or in-out parameter


High level granularity, use case oriented approach:

     Moment-Interval Archetype
 
http://www.step-10.com/SoftwareDesign/ModellingInColour/Moment-Interval.html
     A moment-interval for each function, that will also hold
     in out and in-out parameters, not only the in parameters

     (For object factories, this is popularized by Google
     as the builder pattern, but not all functions are object
     factories)

Bye

sandeep6699@yahoo.com schrieb:
> I want to solicit the opinion of the Java experts about realizing the out-param capability in Java.  Suppose there is a method in a class where I would like to realize the following:
>
> class MyClass {
>      int myMethod(int inIntParam, int outIntParam, double outDoubleParam) {
>          // Accepts inIntParam as input
>          // Updates outIntParam and outDoubleParam
>          // Returns an int
>          …
>      }
>      …
> }
>
> Since primitive types are passed by values, and primitive type wrapper classes are immutable, I am thinking of having outIntParam and outDoubleParam as instance variables in the class, which get set prior to calling myMethod.  Then myMethod can make do with only one parameter i.e.
>
> class MyClass {
>      protected int outIntParam;
>      protected double outDoubleParam;
>
>      int getOutIntParam() {
>          return outIntParam;
>      }
>
>      double getOutDoubleParam() {
>          return outDoubleParam;
>      }
>      //
>      // No Settors for these instance variables
>      // …
>
>      int myMethod(int inIntParam) {
>          // Accepts inIntParam as input
>       // Updates instance variables in outIntParam and outDoubleParam
>      // Returns an int
>      …
>      }
>      …
> }
>
> Kindly suggest if there is a preferred way to realize the same.
>
> Regards,
> Sandeep
>

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Good pattern for realizing the out-param capability in Java? sandeep6699@yahoo.com - 2016-09-14 09:17 -0700
  Re: Good pattern for realizing the out-param capability in Java? Robert Klemme <shortcutter@googlemail.com> - 2016-09-14 18:43 +0200
  Re: Good pattern for realizing the out-param capability in Java? Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-09-14 12:55 -0400
  Re: Good pattern for realizing the out-param capability in Java? j4n bur53 <janburse@fastmail.fm> - 2016-09-14 21:00 +0200
  Re: Good pattern for realizing the out-param capability in Java? Eric Douglas <e.d.programmer@gmail.com> - 2016-09-14 12:54 -0700
    Re: Good pattern for realizing the out-param capability in Java? Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-09-14 17:25 -0400
      Re: Good pattern for realizing the out-param capability in Java? j4n bur53 <janburse@fastmail.fm> - 2016-09-14 23:45 +0200
  Re: Good pattern for realizing the out-param capability in Java? Lew <lewbloch@gmail.com> - 2016-09-14 16:29 -0700

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