Re: Xlint " warning: [unchecked] unchecked conversion"

From:
Lew <lew@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Fri, 24 Jul 2009 09:30:09 -0700 (PDT)
Message-ID:
<22b6d8f4-0aed-455d-9ec5-8545d05bff0f@o36g2000vbl.googlegroups.com>
On Jul 24, 12:05 pm, "Donkey Hottie" <don...@fred.pp.fi> wrote:

"RVic" <rvinc...@hotmail.com> wrote in message

news:4131c823-81b2-4622-bb22-a86435b36f3a@y19g2000yqy.googlegroups.com

Yes, that works, but what then about:

Hashtable getHashtable() {
   return this.hashtable;
 }
 .
 .
 .
public static void main(String[] args) throws Exception {
   Hashtable <String, Vector<String>> ht =
   MyClass.getHashtable(); .
   .
   }

How do I eliminate the "warning: [unchecked] unchecked
conversion" warning for that line in main()? i.e. how do
I put the notation <String, Vector<String>> to the rigth
of the equals sign?


You re-decrade all definitions again.

Hashtable<String, Vector<String, Vector<String>> getHashtable() {
   return this.hashtable;

}


Even better, rename 'this.hashtable' and define as the interface
types:

public class Foo
{
  private final Map <String, List <String>> table =
    new HashMap <String, List <String>> ();
    // or Hashtable, ConcurrentHashMap, ...

  public final Map <String, List <String>> getTable()
  {
    return this.table;
  }
}

You can even make the class generic:

public class Foo <K, T>
{
  private final Map <K, List <T>> table =
    new HashMap <K, List <T>> ();
    // or Hashtable, ConcurrentHashMap, TreeMap, ...
    // but not Hashtable

  public final Map <K, List <T>> getTable()
  {
    return this.table;
  }
}

--
Lew

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