| /* |
| * Copyright (c) 2005, 2016, 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 javax.tools; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| import java.util.Iterator; |
| import java.util.ServiceConfigurationError; |
| import java.util.ServiceLoader; |
| |
| /** |
| * Provides methods for locating tool providers, for example, |
| * providers of compilers. This class complements the |
| * functionality of {@link java.util.ServiceLoader}. |
| * |
| * @author Peter von der Ahé |
| * @since 1.6 |
| */ |
| public class ToolProvider { |
| |
| private static final String systemJavaCompilerModule = "jdk.compiler"; |
| private static final String systemJavaCompilerName = "com.sun.tools.javac.api.JavacTool"; |
| |
| /** |
| * Returns the Java™ programming language compiler provided |
| * with this platform. |
| * <p>The file manager returned by calling |
| * {@link JavaCompiler#getStandardFileManager getStandardFileManager} |
| * on this compiler supports paths provided by any |
| * {@linkplain java.nio.file.FileSystem filesystem}.</p> |
| * @return the compiler provided with this platform or |
| * {@code null} if no compiler is provided |
| * @implNote This implementation returns the compiler provided |
| * by the {@code jdk.compiler} module if that module is available, |
| * and {@code null} otherwise. |
| */ |
| public static JavaCompiler getSystemJavaCompiler() { |
| return getSystemTool(JavaCompiler.class, |
| systemJavaCompilerModule, systemJavaCompilerName); |
| } |
| |
| private static final String systemDocumentationToolModule = "jdk.javadoc"; |
| private static final String systemDocumentationToolName = "jdk.javadoc.internal.api.JavadocTool"; |
| |
| /** |
| * Returns the Java™ programming language documentation tool provided |
| * with this platform. |
| * <p>The file manager returned by calling |
| * {@link DocumentationTool#getStandardFileManager getStandardFileManager} |
| * on this tool supports paths provided by any |
| * {@linkplain java.nio.file.FileSystem filesystem}.</p> |
| * @return the documentation tool provided with this platform or |
| * {@code null} if no documentation tool is provided |
| * @implNote This implementation returns the tool provided |
| * by the {@code jdk.javadoc} module if that module is available, |
| * and {@code null} otherwise. |
| */ |
| public static DocumentationTool getSystemDocumentationTool() { |
| return getSystemTool(DocumentationTool.class, |
| systemDocumentationToolModule, systemDocumentationToolName); |
| } |
| |
| /** |
| * Returns a class loader that may be used to load system tools, |
| * or {@code null} if no such special loader is provided. |
| * @implSpec This implementation always returns {@code null}. |
| * @deprecated This method is subject to removal in a future version of |
| * Java SE. |
| * Use the {@link java.util.spi.ToolProvider system tool provider} or |
| * {@link java.util.ServiceLoader service loader} mechanisms to |
| * locate system tools as well as user-installed tools. |
| * @return a class loader, or {@code null} |
| */ |
| @Deprecated |
| public static ClassLoader getSystemToolClassLoader() { |
| return null; |
| } |
| |
| private static final boolean useLegacy; |
| |
| static { |
| Class<?> c = null; |
| try { |
| c = Class.forName("java.lang.Module"); |
| } catch (Throwable t) { |
| } |
| useLegacy = (c == null); |
| } |
| |
| /** |
| * Get an instance of a system tool using the service loader. |
| * @implNote By default, this returns the implementation in the specified module. |
| * For limited backward compatibility, if this code is run on an older version |
| * of the Java platform that does not support modules, this method will |
| * try and create an instance of the named class. Note that implies the |
| * class must be available on the system class path. |
| * @param <T> the interface of the tool |
| * @param clazz the interface of the tool |
| * @param moduleName the name of the module containing the desired implementation |
| * @param className the class name of the desired implementation |
| * @return the specified implementation of the tool |
| */ |
| private static <T> T getSystemTool(Class<T> clazz, String moduleName, String className) { |
| if (useLegacy) { |
| try { |
| return Class.forName(className, true, ClassLoader.getSystemClassLoader()). |
| asSubclass(clazz).getConstructor().newInstance(); |
| } catch (ReflectiveOperationException e) { |
| throw new Error(e); |
| } |
| } |
| |
| try { |
| ServiceLoader<T> sl = ServiceLoader.load(clazz, ClassLoader.getSystemClassLoader()); |
| for (Iterator<T> iter = sl.iterator(); iter.hasNext(); ) { |
| T tool = iter.next(); |
| if (matches(tool, moduleName)) |
| return tool; |
| } |
| } catch (ServiceConfigurationError e) { |
| throw new Error(e); |
| } |
| return null; |
| } |
| |
| /** |
| * Determine if this is the desired tool instance. |
| * @param <T> the interface of the tool |
| * @param tool the instance of the tool |
| * @param moduleName the name of the module containing the desired implementation |
| * @return true if and only if the tool matches the specified criteria |
| */ |
| private static <T> boolean matches(T tool, String moduleName) { |
| PrivilegedAction<Boolean> pa = () -> { |
| // for now, use reflection to implement |
| // return moduleName.equals(tool.getClass().getModule().getName()); |
| try { |
| Method getModuleMethod = Class.class.getDeclaredMethod("getModule"); |
| Object toolModule = getModuleMethod.invoke(tool.getClass()); |
| Method getNameMethod = toolModule.getClass().getDeclaredMethod("getName"); |
| String toolModuleName = (String) getNameMethod.invoke(toolModule); |
| return moduleName.equals(toolModuleName); |
| } catch (InvocationTargetException | NoSuchMethodException | IllegalAccessException e) { |
| return false; |
| } |
| }; |
| return AccessController.doPrivileged(pa); |
| } |
| } |