jdk8-mips64-public/langtools: comparison src/share/classes/com/sun/tools/javac/util/GraphUtils.java

--1:000000000000
+:959103a6100f
+/*
+* Copyright (c) 1999, 2013, Oracle and/or its affiliates. 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.  Oracle designates this
+* particular file as subject to the "Classpath" exception as provided
+* by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+* or visit www.oracle.com if you need additional information or have any
+* questions.
+*/
+package com.sun.tools.javac.util;
+/** <p><b>This is NOT part of any supported API.
+*  If you write code that depends on this, you do so at your own risk.
+*  This code and its internal interfaces are subject to change or
+*  deletion without notice.</b>
+*/
+public class GraphUtils {
+/**
+* Basic interface for defining various dependency kinds. All dependency kinds
+* must at least support basic capabilities to tell the DOT engine how to render them.
+*/
+public interface DependencyKind {
+/**
+* Returns the DOT representation (to be used in a {@code style} attribute
+* that's most suited for this dependency kind.
+*/
+String getDotStyle();
+}
+/**
+* This class is a basic abstract class for representing a node.
+* A node is associated with a given data.
+*/
+public static abstract class Node<D> {
+public final D data;
+public Node(D data) {
+this.data = data;
+}
+/**
+* Get an array of the dependency kinds supported by this node.
+*/
+public abstract DependencyKind[] getSupportedDependencyKinds();
+/**
+* Get all dependencies, regardless of their kind.
+*/
+public abstract Iterable<? extends Node<D>> getAllDependencies();
+/**
+* Get a name for the dependency (of given kind) linking this node to a given node
+*/
+public abstract String getDependencyName(Node<D> to, DependencyKind dk);
+@Override
+public String toString() {
+return data.toString();
+}
+}
+/**
+* This class specialized Node, by adding elements that are required in order
+* to perform Tarjan computation of strongly connected components.
+*/
+public static abstract class TarjanNode<D> extends Node<D> implements Comparable<TarjanNode<D>> {
+int index = -1;
+int lowlink;
+boolean active;
+public TarjanNode(D data) {
+super(data);
+}
+public abstract Iterable<? extends TarjanNode<D>> getAllDependencies();
+public abstract Iterable<? extends TarjanNode<D>> getDependenciesByKind(DependencyKind dk);
+public int compareTo(TarjanNode<D> o) {
+return (index < o.index) ? -1 : (index == o.index) ? 0 : 1;
+}
+}
+/**
+* Tarjan's algorithm to determine strongly connected components of a
+* directed graph in linear time. Works on TarjanNode.
+*/
+public static <D, N extends TarjanNode<D>> List<? extends List<? extends N>> tarjan(Iterable<? extends N> nodes) {
+ListBuffer<List<N>> cycles = new ListBuffer<>();
+ListBuffer<N> stack = new ListBuffer<>();
+int index = 0;
+for (N node: nodes) {
+if (node.index == -1) {
+index += tarjan(node, index, stack, cycles);
+}
+}
+return cycles.toList();
+}
+private static <D, N extends TarjanNode<D>> int tarjan(N v, int index, ListBuffer<N> stack, ListBuffer<List<N>> cycles) {
+v.index = index;
+v.lowlink = index;
+index++;
+stack.prepend(v);
+v.active = true;
+for (TarjanNode<D> nd: v.getAllDependencies()) {
+@SuppressWarnings("unchecked")
+N n = (N)nd;
+if (n.index == -1) {
+tarjan(n, index, stack, cycles);
+v.lowlink = Math.min(v.lowlink, n.lowlink);
+} else if (stack.contains(n)) {
+v.lowlink = Math.min(v.lowlink, n.index);
+}
+}
+if (v.lowlink == v.index) {
+N n;
+ListBuffer<N> cycle = new ListBuffer<>();
+do {
+n = stack.remove();
+n.active = false;
+cycle.add(n);
+} while (n != v);
+cycles.add(cycle.toList());
+}
+return index;
+}
+/**
+* Debugging: dot representation of a set of connected nodes. The resulting
+* dot representation will use {@code Node.toString} to display node labels
+* and {@code Node.printDependency} to display edge labels. The resulting
+* representation is also customizable with a graph name and a header.
+*/
+public static <D> String toDot(Iterable<? extends TarjanNode<D>> nodes, String name, String header) {
+StringBuilder buf = new StringBuilder();
+buf.append(String.format("digraph %s {\n", name));
+buf.append(String.format("label = \"%s\";\n", header));
+//dump nodes
+for (TarjanNode<D> n : nodes) {
+buf.append(String.format("%s [label = \"%s\"];\n", n.hashCode(), n.toString()));
+}
+//dump arcs
+for (TarjanNode<D> from : nodes) {
+for (DependencyKind dk : from.getSupportedDependencyKinds()) {
+for (TarjanNode<D> to : from.getDependenciesByKind(dk)) {
+buf.append(String.format("%s -> %s [label = \" %s \" style = %s ];\n",
+from.hashCode(), to.hashCode(), from.getDependencyName(to, dk), dk.getDotStyle()));
+}
+}
+}
+buf.append("}\n");
+return buf.toString();
+}
+}

Mercurial > jdk8-mips64-public > langtools / file comparison

comparison: src/share/classes/com/sun/tools/javac/util/GraphUtils.java

src/share/classes/com/sun/tools/javac/util/GraphUtils.java