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/* Glazed Lists (c) 2003-2006 */
/* http://publicobject.com/glazedlists/ publicobject.com,*/
/* O'Dell Engineering Ltd.*/
package ca.odell.glazedlists.impl.matchers;
import ca.odell.glazedlists.matchers.Matcher;
/**
* A simple {@link Matcher} implementation that only matches null objects.
*
* @author James Lemieux
*/
public final class NullMatcher<E> implements Matcher<E> {
/** Singleton instance of NullMatcher. */
private static final Matcher INSTANCE = new NullMatcher();
private NullMatcher() {}
/**
* Return a singleton instance.
*/
public static <E> Matcher<E> getInstance() {
return (Matcher<E>) INSTANCE;
}
/** {@inheritDoc} */
public boolean matches(E item) {
return item == null;
}
/** {@inheritDoc} */
public String toString() {
return "[NullMatcher]";
}
}
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