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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * This code is free software; you can redistribute it and/or modify it

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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

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package com.sun.xml.internal.xsom.util;

import com.sun.xml.internal.xsom.XSType;

/**

 * A simple abstraction for a set of Types that defines containment functions.

 *

 * @author <a href="mailto:Ryan.Shoemaker@Sun.COM">Ryan Shoemaker</a>, Sun Microsystems, Inc.

 */

public abstract class TypeSet {

    /**

     * Return true if this TypeSet contains the specified type.

     *

     * Concrete implementations of this method determine what it

     * means for the TypeSet to "contain" a type.

     *

     * @param type the type

     * @return true iff this TypeSet contains the specified type

     */

    public abstract boolean contains(XSType type);

    /**

     * Calculate the TypeSet formed by the intersection of two

     * other TypeSet objects.

     *

     * @param a a TypeSet

     * @param b another TypeSet

     * @return the intersection of a and b

     */

    public static TypeSet intersection(final TypeSet a, final TypeSet b) {

        return new TypeSet(){

            public boolean contains(XSType type) {

                return a.contains(type) && b.contains(type);

            }

        };

    }

    /**

     * Calculate the TypeSet formed by the union of two

     * other TypeSet objects.

     *

     * @param a a TypeSet

     * @param b another TypeSet

     * @return the union of a and b

     */

    public static TypeSet union(final TypeSet a, final TypeSet b) {

        return new TypeSet(){

            public boolean contains(XSType type) {

                return a.contains(type) || b.contains(type);

            }

        };

    }

}