# IsNull.java

    package org.codefilarete.stalactite.query.model.operator;

    import org.codefilarete.stalactite.query.model.UnitaryOperator;
    import org.codefilarete.stalactite.query.api.Variable;

    /**
     * Represents a "is null" comparison
     *
     * @author Guillaume Mary
     */
    public class IsNull<O> extends UnitaryOperator<O> {

    	public IsNull() {
    		super((O) null);
    	}

    	/**
    	 * Overridden to have no effect since SQL isNll() takes no argument
    	 * @param value any object
    	 */
    	@Override
    	public void setValue(Variable<O> value) {
    		// setting a value on this as no effect because it has no sense
    	}

    	@Override
    	public final boolean isNull() {
    		return true;
    	}
    }