Wed, 16 Oct 2013 16:33:04 -0400
8026286: Improper locking of annotation queues causes assertion failures.
8026063: Calls to annotate.flush() cause incorrect type annotations to be generated.
Summary: Fix locking in ClassReader.java
Reviewed-by: jfranck
1 /*
2 * Copyright (c) 1999, 2013, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
26 package com.sun.tools.javac.util;
28 /** <p><b>This is NOT part of any supported API.
29 * If you write code that depends on this, you do so at your own risk.
30 * This code and its internal interfaces are subject to change or
31 * deletion without notice.</b>
32 */
33 public class GraphUtils {
35 /**
36 * Basic interface for defining various dependency kinds. All dependency kinds
37 * must at least support basic capabilities to tell the DOT engine how to render them.
38 */
39 public interface DependencyKind {
40 /**
41 * Returns the DOT representation (to be used in a {@code style} attribute
42 * that's most suited for this dependency kind.
43 */
44 String getDotStyle();
45 }
47 /**
48 * This class is a basic abstract class for representing a node.
49 * A node is associated with a given data.
50 */
51 public static abstract class Node<D> {
52 public final D data;
54 public Node(D data) {
55 this.data = data;
56 }
58 /**
59 * Get an array of the dependency kinds supported by this node.
60 */
61 public abstract DependencyKind[] getSupportedDependencyKinds();
63 /**
64 * Get all dependencies, regardless of their kind.
65 */
66 public abstract Iterable<? extends Node<D>> getAllDependencies();
68 /**
69 * Get a name for the dependency (of given kind) linking this node to a given node
70 */
71 public abstract String getDependencyName(Node<D> to, DependencyKind dk);
73 @Override
74 public String toString() {
75 return data.toString();
76 }
77 }
79 /**
80 * This class specialized Node, by adding elements that are required in order
81 * to perform Tarjan computation of strongly connected components.
82 */
83 public static abstract class TarjanNode<D> extends Node<D> implements Comparable<TarjanNode<D>> {
84 int index = -1;
85 int lowlink;
86 boolean active;
88 public TarjanNode(D data) {
89 super(data);
90 }
92 public abstract Iterable<? extends TarjanNode<D>> getAllDependencies();
94 public abstract Iterable<? extends TarjanNode<D>> getDependenciesByKind(DependencyKind dk);
96 public int compareTo(TarjanNode<D> o) {
97 return (index < o.index) ? -1 : (index == o.index) ? 0 : 1;
98 }
99 }
101 /**
102 * Tarjan's algorithm to determine strongly connected components of a
103 * directed graph in linear time. Works on TarjanNode.
104 */
105 public static <D, N extends TarjanNode<D>> List<? extends List<? extends N>> tarjan(Iterable<? extends N> nodes) {
106 ListBuffer<List<N>> cycles = new ListBuffer<>();
107 ListBuffer<N> stack = new ListBuffer<>();
108 int index = 0;
109 for (N node: nodes) {
110 if (node.index == -1) {
111 index += tarjan(node, index, stack, cycles);
112 }
113 }
114 return cycles.toList();
115 }
117 private static <D, N extends TarjanNode<D>> int tarjan(N v, int index, ListBuffer<N> stack, ListBuffer<List<N>> cycles) {
118 v.index = index;
119 v.lowlink = index;
120 index++;
121 stack.prepend(v);
122 v.active = true;
123 for (TarjanNode<D> nd: v.getAllDependencies()) {
124 @SuppressWarnings("unchecked")
125 N n = (N)nd;
126 if (n.index == -1) {
127 tarjan(n, index, stack, cycles);
128 v.lowlink = Math.min(v.lowlink, n.lowlink);
129 } else if (stack.contains(n)) {
130 v.lowlink = Math.min(v.lowlink, n.index);
131 }
132 }
133 if (v.lowlink == v.index) {
134 N n;
135 ListBuffer<N> cycle = new ListBuffer<>();
136 do {
137 n = stack.remove();
138 n.active = false;
139 cycle.add(n);
140 } while (n != v);
141 cycles.add(cycle.toList());
142 }
143 return index;
144 }
146 /**
147 * Debugging: dot representation of a set of connected nodes. The resulting
148 * dot representation will use {@code Node.toString} to display node labels
149 * and {@code Node.printDependency} to display edge labels. The resulting
150 * representation is also customizable with a graph name and a header.
151 */
152 public static <D> String toDot(Iterable<? extends TarjanNode<D>> nodes, String name, String header) {
153 StringBuilder buf = new StringBuilder();
154 buf.append(String.format("digraph %s {\n", name));
155 buf.append(String.format("label = \"%s\";\n", header));
156 //dump nodes
157 for (TarjanNode<D> n : nodes) {
158 buf.append(String.format("%s [label = \"%s\"];\n", n.hashCode(), n.toString()));
159 }
160 //dump arcs
161 for (TarjanNode<D> from : nodes) {
162 for (DependencyKind dk : from.getSupportedDependencyKinds()) {
163 for (TarjanNode<D> to : from.getDependenciesByKind(dk)) {
164 buf.append(String.format("%s -> %s [label = \" %s \" style = %s ];\n",
165 from.hashCode(), to.hashCode(), from.getDependencyName(to, dk), dk.getDotStyle()));
166 }
167 }
168 }
169 buf.append("}\n");
170 return buf.toString();
171 }
172 }