Wed, 20 Jun 2012 13:23:26 -0700
7174143: encapsulate doc comment table
Reviewed-by: ksrini, mcimadamore
1 /*
2 * Copyright (c) 2006, 2008, Oracle and/or its affiliates. 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
26 package com.sun.tools.javac.processing;
28 import java.io.BufferedReader;
29 import java.io.FileNotFoundException;
30 import java.io.IOException;
31 import java.io.InputStream;
32 import java.io.InputStreamReader;
33 import java.net.MalformedURLException;
34 import java.net.URL;
36 /**
37 * Utility class to determine if a service can be found on the
38 * path that might be used to create a class loader.
39 *
40 * <p><b>This is NOT part of any supported API.
41 * If you write code that depends on this, you do so at your own risk.
42 * This code and its internal interfaces are subject to change or
43 * deletion without notice.</b>
44 *
45 */
46 // based on sun.misc.Service
47 class ServiceProxy {
48 static class ServiceConfigurationError extends Error {
49 static final long serialVersionUID = 7732091036771098303L;
51 ServiceConfigurationError(String msg) {
52 super(msg);
53 }
54 }
56 private static final String prefix = "META-INF/services/";
58 private static void fail(Class<?> service, String msg)
59 throws ServiceConfigurationError {
60 throw new ServiceConfigurationError(service.getName() + ": " + msg);
61 }
63 private static void fail(Class<?> service, URL u, int line, String msg)
64 throws ServiceConfigurationError {
65 fail(service, u + ":" + line + ": " + msg);
66 }
68 /**
69 * Parse the content of the given URL as a provider-configuration file.
70 *
71 * @param service
72 * The service class for which providers are being sought;
73 * used to construct error detail strings
74 *
75 * @param url
76 * The URL naming the configuration file to be parsed
77 *
78 * @return true if the name of a service is found
79 *
80 * @throws ServiceConfigurationError
81 * If an I/O error occurs while reading from the given URL, or
82 * if a configuration-file format error is detected
83 */
84 private static boolean parse(Class<?> service, URL u) throws ServiceConfigurationError {
85 InputStream in = null;
86 BufferedReader r = null;
87 try {
88 in = u.openStream();
89 r = new BufferedReader(new InputStreamReader(in, "utf-8"));
90 int lc = 1;
91 String ln;
92 while ((ln = r.readLine()) != null) {
93 int ci = ln.indexOf('#');
94 if (ci >= 0) ln = ln.substring(0, ci);
95 ln = ln.trim();
96 int n = ln.length();
97 if (n != 0) {
98 if ((ln.indexOf(' ') >= 0) || (ln.indexOf('\t') >= 0))
99 fail(service, u, lc, "Illegal configuration-file syntax");
100 int cp = ln.codePointAt(0);
101 if (!Character.isJavaIdentifierStart(cp))
102 fail(service, u, lc, "Illegal provider-class name: " + ln);
103 for (int i = Character.charCount(cp); i < n; i += Character.charCount(cp)) {
104 cp = ln.codePointAt(i);
105 if (!Character.isJavaIdentifierPart(cp) && (cp != '.'))
106 fail(service, u, lc, "Illegal provider-class name: " + ln);
107 }
108 return true;
109 }
110 }
111 } catch (FileNotFoundException x) {
112 return false;
113 } catch (IOException x) {
114 fail(service, ": " + x);
115 } finally {
116 try {
117 if (r != null) r.close();
118 } catch (IOException y) {
119 fail(service, ": " + y);
120 }
121 try {
122 if (in != null) in.close();
123 } catch (IOException y) {
124 fail(service, ": " + y);
125 }
126 }
127 return false;
128 }
130 /**
131 * Return true if a description for at least one service is found in the
132 * service configuration files in the given URLs.
133 */
134 public static boolean hasService(Class<?> service, URL[] urls)
135 throws ServiceConfigurationError {
136 for (URL url: urls) {
137 try {
138 String fullName = prefix + service.getName();
139 URL u = new URL(url, fullName);
140 boolean found = parse(service, u);
141 if (found)
142 return true;
143 } catch (MalformedURLException e) {
144 // should not happen; ignore it if it does
145 }
146 }
147 return false;
148 }
149 }