|
1 /* |
|
2 * Copyright 2005-2006 Sun Microsystems, Inc. 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. Sun designates this |
|
8 * particular file as subject to the "Classpath" exception as provided |
|
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
|
22 * CA 95054 USA or visit www.sun.com if you need additional information or |
|
23 * have any questions. |
|
24 */ |
|
25 |
|
26 package javax.tools; |
|
27 |
|
28 import java.io.File; |
|
29 import java.net.URL; |
|
30 import java.net.URLClassLoader; |
|
31 import java.net.MalformedURLException; |
|
32 import java.util.Locale; |
|
33 import java.util.logging.Logger; |
|
34 import java.util.logging.Level; |
|
35 import static java.util.logging.Level.*; |
|
36 |
|
37 /** |
|
38 * Provides methods for locating tool providers, for example, |
|
39 * providers of compilers. This class complements the |
|
40 * functionality of {@link java.util.ServiceLoader}. |
|
41 * |
|
42 * @author Peter von der Ahé |
|
43 * @since 1.6 |
|
44 */ |
|
45 public class ToolProvider { |
|
46 |
|
47 private ToolProvider() {} |
|
48 |
|
49 private static final String propertyName = "sun.tools.ToolProvider"; |
|
50 private static final String loggerName = "javax.tools"; |
|
51 |
|
52 /* |
|
53 * Define the system property "sun.tools.ToolProvider" to enable |
|
54 * debugging: |
|
55 * |
|
56 * java ... -Dsun.tools.ToolProvider ... |
|
57 */ |
|
58 static <T> T trace(Level level, Object reason) { |
|
59 // NOTE: do not make this method private as it affects stack traces |
|
60 try { |
|
61 if (System.getProperty(propertyName) != null) { |
|
62 StackTraceElement[] st = Thread.currentThread().getStackTrace(); |
|
63 String method = "???"; |
|
64 String cls = ToolProvider.class.getName(); |
|
65 if (st.length > 2) { |
|
66 StackTraceElement frame = st[2]; |
|
67 method = String.format((Locale)null, "%s(%s:%s)", |
|
68 frame.getMethodName(), |
|
69 frame.getFileName(), |
|
70 frame.getLineNumber()); |
|
71 cls = frame.getClassName(); |
|
72 } |
|
73 Logger logger = Logger.getLogger(loggerName); |
|
74 if (reason instanceof Throwable) { |
|
75 logger.logp(level, cls, method, |
|
76 reason.getClass().getName(), (Throwable)reason); |
|
77 } else { |
|
78 logger.logp(level, cls, method, String.valueOf(reason)); |
|
79 } |
|
80 } |
|
81 } catch (SecurityException ex) { |
|
82 System.err.format((Locale)null, "%s: %s; %s%n", |
|
83 ToolProvider.class.getName(), |
|
84 reason, |
|
85 ex.getLocalizedMessage()); |
|
86 } |
|
87 return null; |
|
88 } |
|
89 |
|
90 /** |
|
91 * Gets the Java™ programming language compiler provided |
|
92 * with this platform. |
|
93 * @return the compiler provided with this platform or |
|
94 * {@code null} if no compiler is provided |
|
95 */ |
|
96 public static JavaCompiler getSystemJavaCompiler() { |
|
97 if (Lazy.compilerClass == null) |
|
98 return trace(WARNING, "Lazy.compilerClass == null"); |
|
99 try { |
|
100 return Lazy.compilerClass.newInstance(); |
|
101 } catch (Throwable e) { |
|
102 return trace(WARNING, e); |
|
103 } |
|
104 } |
|
105 |
|
106 /** |
|
107 * Returns the class loader for tools provided with this platform. |
|
108 * This does not include user-installed tools. Use the |
|
109 * {@linkplain java.util.ServiceLoader service provider mechanism} |
|
110 * for locating user installed tools. |
|
111 * |
|
112 * @return the class loader for tools provided with this platform |
|
113 * or {@code null} if no tools are provided |
|
114 */ |
|
115 public static ClassLoader getSystemToolClassLoader() { |
|
116 if (Lazy.compilerClass == null) |
|
117 return trace(WARNING, "Lazy.compilerClass == null"); |
|
118 return Lazy.compilerClass.getClassLoader(); |
|
119 } |
|
120 |
|
121 /** |
|
122 * This class will not be initialized until one of the above |
|
123 * methods are called. This ensures that searching for the |
|
124 * compiler does not affect platform start up. |
|
125 */ |
|
126 static class Lazy { |
|
127 private static final String defaultJavaCompilerName |
|
128 = "com.sun.tools.javac.api.JavacTool"; |
|
129 private static final String[] defaultToolsLocation |
|
130 = { "lib", "tools.jar" }; |
|
131 static final Class<? extends JavaCompiler> compilerClass; |
|
132 static { |
|
133 Class<? extends JavaCompiler> c = null; |
|
134 try { |
|
135 c = findClass().asSubclass(JavaCompiler.class); |
|
136 } catch (Throwable t) { |
|
137 trace(WARNING, t); |
|
138 } |
|
139 compilerClass = c; |
|
140 } |
|
141 |
|
142 private static Class<?> findClass() |
|
143 throws MalformedURLException, ClassNotFoundException |
|
144 { |
|
145 try { |
|
146 return enableAsserts(Class.forName(defaultJavaCompilerName, false, null)); |
|
147 } catch (ClassNotFoundException e) { |
|
148 trace(FINE, e); |
|
149 } |
|
150 File file = new File(System.getProperty("java.home")); |
|
151 if (file.getName().equalsIgnoreCase("jre")) |
|
152 file = file.getParentFile(); |
|
153 for (String name : defaultToolsLocation) |
|
154 file = new File(file, name); |
|
155 URL[] urls = {file.toURI().toURL()}; |
|
156 trace(FINE, urls[0].toString()); |
|
157 ClassLoader cl = URLClassLoader.newInstance(urls); |
|
158 cl.setPackageAssertionStatus("com.sun.tools.javac", true); |
|
159 return Class.forName(defaultJavaCompilerName, false, cl); |
|
160 } |
|
161 |
|
162 private static Class<?> enableAsserts(Class<?> cls) { |
|
163 try { |
|
164 ClassLoader loader = cls.getClassLoader(); |
|
165 if (loader != null) |
|
166 loader.setPackageAssertionStatus("com.sun.tools.javac", true); |
|
167 else |
|
168 trace(FINE, "loader == null"); |
|
169 } catch (SecurityException ex) { |
|
170 trace(FINE, ex); |
|
171 } |
|
172 return cls; |
|
173 } |
|
174 } |
|
175 } |