xref: /openjdk9/test/lib/jdk/test/lib/hprof/util/CompositeEnumeration.java

/*
 * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * 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
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */


/*
 * The Original Code is HAT. The Initial Developer of the
 * Original Code is Bill Foote, with contributions from others
 * at JavaSoft/Sun.
 */

package jdk.test.lib.hprof.util;

import java.util.Enumeration;
import java.util.NoSuchElementException;
import jdk.test.lib.hprof.model.JavaHeapObject;

public class CompositeEnumeration implements Enumeration<JavaHeapObject> {
    Enumeration<JavaHeapObject> e1;
    Enumeration<JavaHeapObject> e2;

    public CompositeEnumeration(Enumeration<JavaHeapObject> e1, Enumeration<JavaHeapObject> e2) {
        this.e1 = e1;
        this.e2 = e2;
    }

    public boolean hasMoreElements() {
        return e1.hasMoreElements() || e2.hasMoreElements();
    }

    public JavaHeapObject nextElement() {
        if (e1.hasMoreElements()) {
            return e1.nextElement();
        }

        if (e2.hasMoreElements()) {
            return e2.nextElement();
        }

        throw new NoSuchElementException();
    }
}