Re: Enum and variable problematics

From:
Daniel Pitts <newsgroup.spamfilter@virtualinfinity.net>
Newsgroups:
comp.lang.java.programmer
Date:
Sun, 10 Feb 2008 12:34:31 -0800
Message-ID:
<47af5f96$0$30526$7836cce5@newsrazor.net>
Patricia Shanahan wrote:

jesperkn wrote:
....

In psedu code the following should happend:

For each variable XX in class struct do
{
   System.out.println("name " + XX + " value " + XX.value())
}

Should print out the following:

name aa value 0
name bb value 0
name cc value 0

Is there an easier way to do this, than using enums?

Regards
Jesper


If you really need to do this, why not reflection? Use java.lang.Class
to get the Field[] for the fields you want to see. Use each Field
object's get() to obtain the value.

Patricia

Caveat, reflection in Java tends to over-complicate code.

Perhaps you should consider using an EnumMap instead of actual java fields.

public class DataLog {
    enum FieldName {aa, bb, cc, dd}
    List<FieldName> firstData = java.util.Arrays.asList(aa, bb, dd);
    List<FieldName> secondDaata = java.util.Arrays.asList(aa, bb, cc);

    Map<FieldName, String> data =
         new EnumMap<FieldName, String>(FieldName.class);

    public void set(List<FieldName> fields, String value) {
      for (FieldName field: fields) {
         set(field, value);
      }
    }
    public void set(FieldName field, String value) {
      data.put(field, value);
    }
}

Much *much* cleaner than reflection.

--
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