Name: jl125535 Date: 02/25/2004


FULL PRODUCT VERSION :
java version "1.5.0-beta2"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0-beta2-b39)
Java HotSpot(TM) Client VM (build 1.5.0-beta2-b39, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows 2000 [Version 5.00.2195]

A DESCRIPTION OF THE PROBLEM :
The new for construct fails to find iterator() when defined as second upper bound. See comment in following:

    public <T extends Runnable & Iterable<String>> void bar( T t){
        for( String e : t) //This line does not run
           out.println(e.toUpperCase());

        for(Iterator<String> i = t.iterator(); i.hasNext();)
            out.println( i.next().toUpperCase());
        t.run();
    }

The second, traditional iteration, works well.

Swap the bounds, and it finds the iterator. Like:
public <T extends Iterable<String> & Runnable> void bar( T t){....

Seems like the the new for construct forgets about casting. The bytecode seem like:
public void bar(Runnable t)
{
  for(Iterator i = t.iterator();....
  ..
  for(Iterator i = ((Iterable)t).iterator(); ....
  ..
  t.run();
.. and a Runnable does not have a iterator()


ERROR MESSAGES/STACK TRACES THAT OCCUR :
java.lang.NoSuchMethodError: java.lang.Runnable.iterator()

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.Iterator;
import java.util.Arrays;
import java.util.List;
import static java.lang.System.out;


public class Foo implements Runnable, Iterable<String>{
    
    public <T extends Runnable & Iterable<String>> void bar( T t){
        for( String e : t) //This line does not run
            out.println(e.toUpperCase());

        for(Iterator<String> i = t.iterator(); i.hasNext();)
            out.println( i.next().toUpperCase());
        t.run();
    }
    
    public void run(){
        out.println("Running");
    }
    
    public Iterator<String> iterator(){
        List<String> list = Arrays.asList(new String[]{"Adam", "Eve"});
        return list.iterator();
    }
    
    public static void main(String... args) {
        Foo foo = new Foo();
        foo.bar( foo);
    }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
 swap the bounds
(Incident Review ID: 240088)
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