| /* |
| * Copyright (c) 1997, 2021 Oracle and/or its affiliates. All rights reserved. |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Distribution License v. 1.0, which is available at |
| * http://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * SPDX-License-Identifier: BSD-3-Clause |
| */ |
| |
| package org.glassfish.jaxb.core.v2.util; |
| |
| import java.util.Iterator; |
| import java.util.Map; |
| import java.util.NoSuchElementException; |
| |
| /** |
| * {@link Iterator} that walks over a map of maps. |
| * |
| * @author Kohsuke Kawaguchi |
| * @since 2.0 |
| */ |
| public final class FlattenIterator<T> implements Iterator<T> { |
| |
| private final Iterator<? extends Map<?,? extends T>> parent; |
| private Iterator<? extends T> child = null; |
| private T next; |
| |
| public FlattenIterator( Iterable<? extends Map<?,? extends T>> core ) { |
| this.parent = core.iterator(); |
| } |
| |
| |
| public void remove() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean hasNext() { |
| getNext(); |
| return next!=null; |
| } |
| |
| public T next() { |
| T r = next; |
| next = null; |
| if(r==null) |
| throw new NoSuchElementException(); |
| return r; |
| } |
| |
| private void getNext() { |
| if(next!=null) return; |
| |
| if(child!=null && child.hasNext()) { |
| next = child.next(); |
| return; |
| } |
| // child is empty |
| if(parent.hasNext()) { |
| child = parent.next().values().iterator(); |
| getNext(); |
| } |
| // else |
| // no more object |
| } |
| } |