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/*
* Copyright (c) 1998, 2011, 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.
*/
package sun.misc;
import java.util.Enumeration;
import java.util.NoSuchElementException;
/*
* A useful utility class that will enumerate over an array of
* enumerations.
*/
public class CompoundEnumeration<E> implements Enumeration<E> {
private Enumeration<E>[] enums;
private int index = 0;
public CompoundEnumeration(Enumeration<E>[] enums) {
this.enums = enums;
}
private boolean next() {
while (index < enums.length) {
if (enums[index] != null && enums[index].hasMoreElements()) {
return true;
}
index++;
}
return false;
}
public boolean hasMoreElements() {
return next();
}
public E nextElement() {
if (!next()) {
throw new NoSuchElementException();
}
return enums[index].nextElement();
}
}
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