GroupAggregator and DistinctValues woes

Question

Hi --
I have crafted a contrived TestCase and I just can't get the thing to output the results I expect.
Posting the classes (TestCase/Person), followed by the output I get, followed by the output I would have thought I should get.
Running on Mac OS 10.5.5, single node, stock configuration (not specified a custom XML config file) and the TestCase class is run with local storage set to false. Using the 3.4 download I picked up yesterday from the Oracle site; we also use 3.4 at work.
Any help appreciated!
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// TestCase.java - the main class
package org.foo;
import com.tangosol.net.CacheFactory;
import com.tangosol.net.NamedCache;
import com.tangosol.util.NullFilter;
import com.tangosol.util.aggregator.DistinctValues;
import com.tangosol.util.aggregator.GroupAggregator;
public class TestCase {
     public static void main(String[] args) {
          // get a stock cache - no custom config
          NamedCache cache = CacheFactory.getCache("theCache");
          cache.clear();
          // add some people to the cache
          cache.put(1, new Person(1, "Albert"));
          cache.put(2, new Person(2, "Albert"));
          cache.put(3, new Person(3, "Albert"));
          cache.put(4, new Person(4, "Cindy"));
          // i want to find the id's of employees who share the same name, so i group by name
          GroupAggregator ga = GroupAggregator.createInstance("getName", new DistinctValues("getId"));
          // do the aggregation
          Object result = cache.aggregate(new NullFilter(), ga);
          // dump the result
          System.out.println(result);
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package org.foo;
import java.io.Serializable;
public class Person implements Serializable {
     private int id;
     private String name;
     public Person(int id, String name) {
          this.id = id;
          this.name = name;
     public int getId() {
          return id;
     public String getName() {
          return name;
     public int hashCode() {
          final int prime = 31;
          int result = 1;
          result = prime * result + id;
          return result;
     public boolean equals(Object obj) {
          if (this == obj)
               return true;
          if (obj == null)
               return false;
          if (getClass() != obj.getClass())
               return false;
          Person other = (Person) obj;
          if (id != other.id)
               return false;
          return true;
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ACTUAL OUTPUT: {Cindy=[3, 1, 2], Albert=[3, 1, 2]}
EXPECTED OUTPUT: {Cindy=[4], Albert=[3, 1, 2]}
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Answer 1

Hi good stuff,
If will work as expected if you change your TestCase to
// i want to find the id's of employees who share the same name, so i group by name
        GroupAggregator ga = GroupAggregator.createInstance("getName", new MyDistinctValues("getId"));where MyDistinctValues is
import com.tangosol.util.ValueExtractor;
import com.tangosol.util.aggregator.DistinctValues;
import java.util.Set;
import java.util.HashSet;
import java.util.Collection;
* dimitri Oct 6, 2008 12:50:08 AM
public class MyDistinctValues extends DistinctValues
    public MyDistinctValues()
        super();
    public MyDistinctValues(ValueExtractor extractor)
        super(extractor);
    public MyDistinctValues(String sMethod)
        super(sMethod);
    public Object aggregate(Set setEntries)
        Set setResults = (Set) super.aggregate(setEntries);
        return new HashSet(setResults);
    public Object aggregateResults(Collection collResults)
        Set setResults = (Set) super.aggregateResults(collResults);
        return new HashSet(setResults);
    }Regards,
Dimitri