1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/classes/javax/tools/ToolProvider.java Sat Dec 01 00:00:00 2007 +0000
1.3 @@ -0,0 +1,175 @@
1.4 +/*
1.5 + * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation. Sun designates this
1.11 + * particular file as subject to the "Classpath" exception as provided
1.12 + * by Sun in the LICENSE file that accompanied this code.
1.13 + *
1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.16 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.17 + * version 2 for more details (a copy is included in the LICENSE file that
1.18 + * accompanied this code).
1.19 + *
1.20 + * You should have received a copy of the GNU General Public License version
1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.23 + *
1.24 + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.25 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.26 + * have any questions.
1.27 + */
1.28 +
1.29 +package javax.tools;
1.30 +
1.31 +import java.io.File;
1.32 +import java.net.URL;
1.33 +import java.net.URLClassLoader;
1.34 +import java.net.MalformedURLException;
1.35 +import java.util.Locale;
1.36 +import java.util.logging.Logger;
1.37 +import java.util.logging.Level;
1.38 +import static java.util.logging.Level.*;
1.39 +
1.40 +/**
1.41 + * Provides methods for locating tool providers, for example,
1.42 + * providers of compilers. This class complements the
1.43 + * functionality of {@link java.util.ServiceLoader}.
1.44 + *
1.45 + * @author Peter von der Ahé
1.46 + * @since 1.6
1.47 + */
1.48 +public class ToolProvider {
1.49 +
1.50 + private ToolProvider() {}
1.51 +
1.52 + private static final String propertyName = "sun.tools.ToolProvider";
1.53 + private static final String loggerName = "javax.tools";
1.54 +
1.55 + /*
1.56 + * Define the system property "sun.tools.ToolProvider" to enable
1.57 + * debugging:
1.58 + *
1.59 + * java ... -Dsun.tools.ToolProvider ...
1.60 + */
1.61 + static <T> T trace(Level level, Object reason) {
1.62 + // NOTE: do not make this method private as it affects stack traces
1.63 + try {
1.64 + if (System.getProperty(propertyName) != null) {
1.65 + StackTraceElement[] st = Thread.currentThread().getStackTrace();
1.66 + String method = "???";
1.67 + String cls = ToolProvider.class.getName();
1.68 + if (st.length > 2) {
1.69 + StackTraceElement frame = st[2];
1.70 + method = String.format((Locale)null, "%s(%s:%s)",
1.71 + frame.getMethodName(),
1.72 + frame.getFileName(),
1.73 + frame.getLineNumber());
1.74 + cls = frame.getClassName();
1.75 + }
1.76 + Logger logger = Logger.getLogger(loggerName);
1.77 + if (reason instanceof Throwable) {
1.78 + logger.logp(level, cls, method,
1.79 + reason.getClass().getName(), (Throwable)reason);
1.80 + } else {
1.81 + logger.logp(level, cls, method, String.valueOf(reason));
1.82 + }
1.83 + }
1.84 + } catch (SecurityException ex) {
1.85 + System.err.format((Locale)null, "%s: %s; %s%n",
1.86 + ToolProvider.class.getName(),
1.87 + reason,
1.88 + ex.getLocalizedMessage());
1.89 + }
1.90 + return null;
1.91 + }
1.92 +
1.93 + /**
1.94 + * Gets the Java™ programming language compiler provided
1.95 + * with this platform.
1.96 + * @return the compiler provided with this platform or
1.97 + * {@code null} if no compiler is provided
1.98 + */
1.99 + public static JavaCompiler getSystemJavaCompiler() {
1.100 + if (Lazy.compilerClass == null)
1.101 + return trace(WARNING, "Lazy.compilerClass == null");
1.102 + try {
1.103 + return Lazy.compilerClass.newInstance();
1.104 + } catch (Throwable e) {
1.105 + return trace(WARNING, e);
1.106 + }
1.107 + }
1.108 +
1.109 + /**
1.110 + * Returns the class loader for tools provided with this platform.
1.111 + * This does not include user-installed tools. Use the
1.112 + * {@linkplain java.util.ServiceLoader service provider mechanism}
1.113 + * for locating user installed tools.
1.114 + *
1.115 + * @return the class loader for tools provided with this platform
1.116 + * or {@code null} if no tools are provided
1.117 + */
1.118 + public static ClassLoader getSystemToolClassLoader() {
1.119 + if (Lazy.compilerClass == null)
1.120 + return trace(WARNING, "Lazy.compilerClass == null");
1.121 + return Lazy.compilerClass.getClassLoader();
1.122 + }
1.123 +
1.124 + /**
1.125 + * This class will not be initialized until one of the above
1.126 + * methods are called. This ensures that searching for the
1.127 + * compiler does not affect platform start up.
1.128 + */
1.129 + static class Lazy {
1.130 + private static final String defaultJavaCompilerName
1.131 + = "com.sun.tools.javac.api.JavacTool";
1.132 + private static final String[] defaultToolsLocation
1.133 + = { "lib", "tools.jar" };
1.134 + static final Class<? extends JavaCompiler> compilerClass;
1.135 + static {
1.136 + Class<? extends JavaCompiler> c = null;
1.137 + try {
1.138 + c = findClass().asSubclass(JavaCompiler.class);
1.139 + } catch (Throwable t) {
1.140 + trace(WARNING, t);
1.141 + }
1.142 + compilerClass = c;
1.143 + }
1.144 +
1.145 + private static Class<?> findClass()
1.146 + throws MalformedURLException, ClassNotFoundException
1.147 + {
1.148 + try {
1.149 + return enableAsserts(Class.forName(defaultJavaCompilerName, false, null));
1.150 + } catch (ClassNotFoundException e) {
1.151 + trace(FINE, e);
1.152 + }
1.153 + File file = new File(System.getProperty("java.home"));
1.154 + if (file.getName().equalsIgnoreCase("jre"))
1.155 + file = file.getParentFile();
1.156 + for (String name : defaultToolsLocation)
1.157 + file = new File(file, name);
1.158 + URL[] urls = {file.toURI().toURL()};
1.159 + trace(FINE, urls[0].toString());
1.160 + ClassLoader cl = URLClassLoader.newInstance(urls);
1.161 + cl.setPackageAssertionStatus("com.sun.tools.javac", true);
1.162 + return Class.forName(defaultJavaCompilerName, false, cl);
1.163 + }
1.164 +
1.165 + private static Class<?> enableAsserts(Class<?> cls) {
1.166 + try {
1.167 + ClassLoader loader = cls.getClassLoader();
1.168 + if (loader != null)
1.169 + loader.setPackageAssertionStatus("com.sun.tools.javac", true);
1.170 + else
1.171 + trace(FINE, "loader == null");
1.172 + } catch (SecurityException ex) {
1.173 + trace(FINE, ex);
1.174 + }
1.175 + return cls;
1.176 + }
1.177 + }
1.178 +}
