| /* |
| * Copyright 2006 Sun Microsystems, Inc. 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. Sun designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| */ |
| package com.sun.xml.internal.xsom.impl.util; |
| |
| import java.util.Iterator; |
| |
| /** |
| * {@link Iterator} that works as a filter to another {@link Iterator}. |
| * |
| * @author |
| * Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com) |
| */ |
| public abstract class FilterIterator implements Iterator { |
| |
| private final Iterator core; |
| private Object next; |
| |
| protected FilterIterator( Iterator core ) { |
| this.core = core; |
| } |
| |
| /** |
| * Implemented by the derived class to filter objects. |
| * |
| * @return true |
| * to let the iterator return the object to the client. |
| */ |
| protected abstract boolean allows( Object o ); |
| |
| public boolean hasNext() { |
| while(next==null && core.hasNext()) { |
| // fetch next |
| Object o = core.next(); |
| if( allows(o) ) |
| next = o; |
| } |
| return next!=null; |
| } |
| |
| public Object next() { |
| Object r = next; |
| next = null; |
| return r; |
| } |
| |
| public void remove() { |
| throw new UnsupportedOperationException(); |
| } |
| } |