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 package org.graalvm.compiler.graph; 24 25 import java.util.Iterator; 26 27 /** 28 * Iterates over the nodes in a given graph. 29 */ 30 class GraphNodeIterator implements Iterator<Node> { 31 32 private final Graph graph; 33 private int index; 34 35 GraphNodeIterator(Graph graph) { 36 this(graph, 0); 37 } 38 39 GraphNodeIterator(Graph graph, int index) { 40 this.graph = graph; 41 this.index = index - 1; 42 forward(); 43 } 44 45 private void forward() { 46 if (index < graph.nodesSize) { 47 do { 48 index++; 49 } while (index < graph.nodesSize && graph.nodes[index] == null); 50 } 51 } 52 53 @Override 54 public boolean hasNext() { 55 checkForDeletedNode(); 56 return index < graph.nodesSize; 57 } 58 59 private void checkForDeletedNode() { 60 while (index < graph.nodesSize && graph.nodes[index] == null) { 61 index++; 62 } 63 } 64 65 @Override 66 public Node next() { 67 try { 68 return graph.nodes[index]; 69 } finally { 70 forward(); 71 } 72 } 73 74 @Override 75 public void remove() { 76 throw new UnsupportedOperationException(); 77 } 78 }