1 /*
   2  * Copyright (c) 2011, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 
  25 package org.graalvm.compiler.graph.iterators;
  26 
  27 import java.util.Iterator;
  28 
  29 import org.graalvm.compiler.graph.Node;
  30 
  31 public class PredicatedProxyNodeIterator<T extends Node> extends NodeIterator<T> {
  32 
  33     private final Iterator<T> iterator;
  34     private final NodePredicate predicate;
  35 
  36     public PredicatedProxyNodeIterator(Iterator<T> iterator, NodePredicate predicate) {
  37         this.iterator = iterator;
  38         this.predicate = predicate;
  39     }
  40 
  41     @Override
  42     protected void forward() {
  43         while ((current == null || !current.isAlive() || !predicate.apply(current)) && iterator.hasNext()) {
  44             current = iterator.next();
  45         }
  46         if (current != null && (!current.isAlive() || !predicate.apply(current))) {
  47             current = null;
  48         }
  49     }
  50 }