NullType.java

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/*
 * NullType.java
 *
 * Created on March 8, 2000
 */

package com.sun.jdo.spi.persistence.support.sqlstore.query.util.type;

/**
 * This class represents the type of null.
 *
 * @author  Michael Bouschen
 * @version 0.1
 */
public class NullType
    extends Type
{
    /**
     *
     */
    NullType()
    {
        super("null", void.class); //NOI18N
    }

    /**
     * An NullType object is compatible to
     * - the errorType object
     * - an object of type NullType (to itself)
     * - an object of type ClassType
     */
    public boolean isCompatibleWith(Type type)
    {
        return (type.equals(TypeTable.errorType) ||
                (type instanceof NullType) ||
                (type instanceof ClassType));
    }


}