1 /* 2 * Copyright (c) 2014, 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; 26 27 import java.util.Iterator; 28 29 /** 30 * Iterates over the nodes in a given graph. 31 */ 32 class GraphNodeIterator implements Iterator<Node> { 33 34 private final Graph graph; 35 private int index; 36 37 GraphNodeIterator(Graph graph) { 38 this(graph, 0); 39 } 40 41 GraphNodeIterator(Graph graph, int index) { 42 this.graph = graph; 43 this.index = index - 1; 44 forward(); 45 } 46 47 private void forward() { 48 if (index < graph.nodesSize) { 49 do { 50 index++; 51 } while (index < graph.nodesSize && graph.nodes[index] == null); 52 } 53 } 54 55 @Override 56 public boolean hasNext() { 57 checkForDeletedNode(); 58 return index < graph.nodesSize; 59 } 60 61 private void checkForDeletedNode() { 62 while (index < graph.nodesSize && graph.nodes[index] == null) { 63 index++; 64 } 65 } 66 67 @Override 68 public Node next() { 69 try { 70 return graph.nodes[index]; 71 } finally { 72 forward(); 73 } 74 } 75 76 @Override 77 public void remove() { 78 throw new UnsupportedOperationException(); 79 } 80 }