/*
* (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Contributors:
* bstefanescu
*/
package org.nuxeo.ecm.webengine.jaxrs.servlet;
import java.util.Enumeration;
import java.util.NoSuchElementException;
/**
* @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a>
*/
public class CompoundEnumeration<E> implements Enumeration<E> {
private final Enumeration<E>[] enums;
private int index = 0;
@SuppressWarnings("unchecked")
public CompoundEnumeration(Enumeration<?>[] enums) {
this.enums = (Enumeration<E>[]) enums;
}
private boolean next() {
while (index < enums.length) {
if (enums[index] != null && enums[index].hasMoreElements()) {
return true;
}
index++;
}
return false;
}
@Override
public boolean hasMoreElements() {
return next();
}
@Override
public E nextElement() {
if (!next()) {
throw new NoSuchElementException();
}
return enums[index].nextElement();
}
}