src/share/classes/javax/tools/ToolProvider.java

Mon, 10 Dec 2012 16:21:26 +0000

author
vromero
date
Mon, 10 Dec 2012 16:21:26 +0000
changeset 1442
fcf89720ae71
parent 1413
bdcef2ef52d2
child 2525
2eb010b6cb22
permissions
-rw-r--r--

8003967: detect and remove all mutable implicit static enum fields in langtools
Reviewed-by: jjg

duke@1 1 /*
jjg@1413 2 * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved.
duke@1 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@1 4 *
duke@1 5 * This code is free software; you can redistribute it and/or modify it
duke@1 6 * under the terms of the GNU General Public License version 2 only, as
ohair@554 7 * published by the Free Software Foundation. Oracle designates this
duke@1 8 * particular file as subject to the "Classpath" exception as provided
ohair@554 9 * by Oracle in the LICENSE file that accompanied this code.
duke@1 10 *
duke@1 11 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@1 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@1 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@1 14 * version 2 for more details (a copy is included in the LICENSE file that
duke@1 15 * accompanied this code).
duke@1 16 *
duke@1 17 * You should have received a copy of the GNU General Public License version
duke@1 18 * 2 along with this work; if not, write to the Free Software Foundation,
duke@1 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@1 20 *
ohair@554 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
ohair@554 22 * or visit www.oracle.com if you need additional information or have any
ohair@554 23 * questions.
duke@1 24 */
duke@1 25
duke@1 26 package javax.tools;
duke@1 27
duke@1 28 import java.io.File;
jjg@659 29 import java.lang.ref.Reference;
jjg@659 30 import java.lang.ref.WeakReference;
duke@1 31 import java.net.URL;
duke@1 32 import java.net.URLClassLoader;
duke@1 33 import java.net.MalformedURLException;
jjg@659 34 import java.util.HashMap;
duke@1 35 import java.util.Locale;
jjg@659 36 import java.util.Map;
duke@1 37 import java.util.logging.Logger;
duke@1 38 import java.util.logging.Level;
duke@1 39 import static java.util.logging.Level.*;
duke@1 40
duke@1 41 /**
duke@1 42 * Provides methods for locating tool providers, for example,
duke@1 43 * providers of compilers. This class complements the
duke@1 44 * functionality of {@link java.util.ServiceLoader}.
duke@1 45 *
duke@1 46 * @author Peter von der Ahé
duke@1 47 * @since 1.6
duke@1 48 */
duke@1 49 public class ToolProvider {
duke@1 50
duke@1 51 private static final String propertyName = "sun.tools.ToolProvider";
duke@1 52 private static final String loggerName = "javax.tools";
duke@1 53
duke@1 54 /*
duke@1 55 * Define the system property "sun.tools.ToolProvider" to enable
duke@1 56 * debugging:
duke@1 57 *
duke@1 58 * java ... -Dsun.tools.ToolProvider ...
duke@1 59 */
duke@1 60 static <T> T trace(Level level, Object reason) {
duke@1 61 // NOTE: do not make this method private as it affects stack traces
duke@1 62 try {
duke@1 63 if (System.getProperty(propertyName) != null) {
duke@1 64 StackTraceElement[] st = Thread.currentThread().getStackTrace();
duke@1 65 String method = "???";
duke@1 66 String cls = ToolProvider.class.getName();
duke@1 67 if (st.length > 2) {
duke@1 68 StackTraceElement frame = st[2];
duke@1 69 method = String.format((Locale)null, "%s(%s:%s)",
duke@1 70 frame.getMethodName(),
duke@1 71 frame.getFileName(),
duke@1 72 frame.getLineNumber());
duke@1 73 cls = frame.getClassName();
duke@1 74 }
duke@1 75 Logger logger = Logger.getLogger(loggerName);
duke@1 76 if (reason instanceof Throwable) {
duke@1 77 logger.logp(level, cls, method,
duke@1 78 reason.getClass().getName(), (Throwable)reason);
duke@1 79 } else {
duke@1 80 logger.logp(level, cls, method, String.valueOf(reason));
duke@1 81 }
duke@1 82 }
duke@1 83 } catch (SecurityException ex) {
duke@1 84 System.err.format((Locale)null, "%s: %s; %s%n",
duke@1 85 ToolProvider.class.getName(),
duke@1 86 reason,
duke@1 87 ex.getLocalizedMessage());
duke@1 88 }
duke@1 89 return null;
duke@1 90 }
duke@1 91
jjg@659 92 private static final String defaultJavaCompilerName
jjg@659 93 = "com.sun.tools.javac.api.JavacTool";
jjg@659 94
duke@1 95 /**
duke@1 96 * Gets the Java&trade; programming language compiler provided
duke@1 97 * with this platform.
duke@1 98 * @return the compiler provided with this platform or
duke@1 99 * {@code null} if no compiler is provided
duke@1 100 */
duke@1 101 public static JavaCompiler getSystemJavaCompiler() {
jjg@659 102 return instance().getSystemTool(JavaCompiler.class, defaultJavaCompilerName);
duke@1 103 }
duke@1 104
jjg@1413 105 private static final String defaultDocumentationToolName
jjg@1413 106 = "com.sun.tools.javadoc.api.JavadocTool";
jjg@1413 107
jjg@1413 108 /**
jjg@1413 109 * Gets the Java&trade; programming language documentation tool provided
jjg@1413 110 * with this platform.
jjg@1413 111 * @return the documentation tool provided with this platform or
jjg@1413 112 * {@code null} if no documentation tool is provided
jjg@1413 113 */
jjg@1413 114 public static DocumentationTool getSystemDocumentationTool() {
jjg@1413 115 return instance().getSystemTool(DocumentationTool.class, defaultDocumentationToolName);
jjg@1413 116 }
jjg@1413 117
duke@1 118 /**
duke@1 119 * Returns the class loader for tools provided with this platform.
duke@1 120 * This does not include user-installed tools. Use the
duke@1 121 * {@linkplain java.util.ServiceLoader service provider mechanism}
duke@1 122 * for locating user installed tools.
duke@1 123 *
duke@1 124 * @return the class loader for tools provided with this platform
duke@1 125 * or {@code null} if no tools are provided
duke@1 126 */
duke@1 127 public static ClassLoader getSystemToolClassLoader() {
jjg@659 128 try {
jjg@659 129 Class<? extends JavaCompiler> c =
jjg@659 130 instance().getSystemToolClass(JavaCompiler.class, defaultJavaCompilerName);
jjg@659 131 return c.getClassLoader();
jjg@659 132 } catch (Throwable e) {
jjg@659 133 return trace(WARNING, e);
jjg@659 134 }
duke@1 135 }
duke@1 136
jjg@659 137
jjg@659 138 private static ToolProvider instance;
jjg@659 139
jjg@659 140 private static synchronized ToolProvider instance() {
jjg@659 141 if (instance == null)
jjg@659 142 instance = new ToolProvider();
jjg@659 143 return instance;
jjg@659 144 }
jjg@659 145
jjg@659 146 // Cache for tool classes.
jjg@659 147 // Use weak references to avoid keeping classes around unnecessarily
jjg@659 148 private Map<String, Reference<Class<?>>> toolClasses = new HashMap<String, Reference<Class<?>>>();
jjg@659 149
jjg@659 150 // Cache for tool classloader.
jjg@659 151 // Use a weak reference to avoid keeping it around unnecessarily
jjg@659 152 private Reference<ClassLoader> refToolClassLoader = null;
jjg@659 153
jjg@659 154
jjg@659 155 private ToolProvider() { }
jjg@659 156
jjg@659 157 private <T> T getSystemTool(Class<T> clazz, String name) {
jjg@659 158 Class<? extends T> c = getSystemToolClass(clazz, name);
jjg@659 159 try {
jjg@659 160 return c.asSubclass(clazz).newInstance();
jjg@659 161 } catch (Throwable e) {
jjg@659 162 trace(WARNING, e);
jjg@659 163 return null;
jjg@659 164 }
jjg@659 165 }
jjg@659 166
jjg@659 167 private <T> Class<? extends T> getSystemToolClass(Class<T> clazz, String name) {
jjg@659 168 Reference<Class<?>> refClass = toolClasses.get(name);
jjg@659 169 Class<?> c = (refClass == null ? null : refClass.get());
jjg@659 170 if (c == null) {
duke@1 171 try {
jjg@659 172 c = findSystemToolClass(name);
jjg@659 173 } catch (Throwable e) {
jjg@659 174 return trace(WARNING, e);
duke@1 175 }
jjg@659 176 toolClasses.put(name, new WeakReference<Class<?>>(c));
jjg@659 177 }
jjg@659 178 return c.asSubclass(clazz);
jjg@659 179 }
jjg@659 180
jjg@659 181 private static final String[] defaultToolsLocation = { "lib", "tools.jar" };
jjg@659 182
jjg@659 183 private Class<?> findSystemToolClass(String toolClassName)
jjg@659 184 throws MalformedURLException, ClassNotFoundException
jjg@659 185 {
jjg@659 186 // try loading class directly, in case tool is on the bootclasspath
jjg@659 187 try {
jjg@816 188 return Class.forName(toolClassName, false, null);
jjg@659 189 } catch (ClassNotFoundException e) {
jjg@659 190 trace(FINE, e);
jjg@659 191
jjg@659 192 // if tool not on bootclasspath, look in default tools location (tools.jar)
jjg@659 193 ClassLoader cl = (refToolClassLoader == null ? null : refToolClassLoader.get());
jjg@659 194 if (cl == null) {
jjg@659 195 File file = new File(System.getProperty("java.home"));
jjg@659 196 if (file.getName().equalsIgnoreCase("jre"))
jjg@659 197 file = file.getParentFile();
jjg@659 198 for (String name : defaultToolsLocation)
jjg@659 199 file = new File(file, name);
jjg@659 200
jjg@659 201 // if tools not found, no point in trying a URLClassLoader
jjg@659 202 // so rethrow the original exception.
jjg@659 203 if (!file.exists())
jjg@659 204 throw e;
jjg@659 205
jjg@659 206 URL[] urls = { file.toURI().toURL() };
jjg@659 207 trace(FINE, urls[0].toString());
jjg@659 208
jjg@659 209 cl = URLClassLoader.newInstance(urls);
jjg@659 210 refToolClassLoader = new WeakReference<ClassLoader>(cl);
jjg@659 211 }
jjg@659 212
jjg@659 213 return Class.forName(toolClassName, false, cl);
duke@1 214 }
jjg@659 215 }
duke@1 216 }

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