Re: Checking if values are the same

From:

Lew <lew@lewscanon.com>

Newsgroups:

comp.lang.java.programmer

Date:

Sun, 28 Oct 2007 14:36:16 -0400

Message-ID:

<a8SdnVjojc89S7nanZ2dnUVZ_ozinZ2d@comcast.com>

francan00@yahoo.com wrote:

I currently have two String objects I check to find out if they are
the same value:

String str1 = "red";
String str2 = "yellow";
if (str1.equals(str2)){
System.out.println("Equal");
}
else{
System.out.println("Not equal");
}

Now I need to check 10 objects. How would I check 10 objects to find
out if any of them have the same value?

Variations on:

Collection <Thing> mightHaveDupes = getSomeCollection();
Collection <Thing> noDupes = new WhateverCollection <Thing> ();
// we'll get back to which Collection implementation to use

for ( Thing thing : mightHaveDupes )
{
  if ( noDupes.contains( thing ))
  {
   log( "Thing {"+ thing +"} is duplicated." );
  }
  else
  {
   noDupes.add( thing );
  }
}

If the copy is a Set, then duplication is avoided automatically:

public <T> boolean hasDupes( Collection<T> mayHave )
{
   Set<T> copy = new HashSet<T> ( mayHave );
   return (copy.size() < mayHave.size());
}

--
Lew