Question on Generics Syntax

Hi,

I'm going crazy with the proper syntax of Collections.binarySearch():

http://java.sun.com/javase/6/docs/api/java/util/Collections.html#binarySearch(java.util.List,%20T,%20java.util.Comparator)

I've been searching Google and Google Groups for similar questions,
but, while this question has been asked before, the answers don't seem
to apply to my case. This is my code:

import java.util.Collections;

public class Glossary {
    final private List<GlossaryTerm> gList;

    public Glossary() {
        this.gList = new ArrayList<GlossaryTerm>();
    }

    public void addGlossaryTerm(String original, String comment) {
        GlossaryTerm gt = new GlossaryTerm(original, comment);

        if (Collections.binarySearch(gList, gt) < 0) {
            gList.add(gt);
        }
    }
}

On compiling, I get this error:

....Glossary.java:107: cannot find symbol
symbol : method
binarySearch(java.util.List<net.localizethat.datamodel.GlossaryTerm>,net.localizethat.datamodel.GlossaryTerm)
location: class java.util.Collections
        if (Collections.binarySearch(gList, gt) < 0) {

and I fail to see where is the error. During search, I've visited:

http://mindprod.com/jgloss/binarysearch.html

and I can't see the difference between the example Roedy put there
(BTW, thanks, Roedy!) and my code. Can anyone help me, please?

TIA