| /* |
| * Copyright (c) 2006, 2012, 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 com.sun.tools.javac.processing; |
| |
| import java.io.BufferedReader; |
| import java.io.FileNotFoundException; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.InputStreamReader; |
| import java.net.MalformedURLException; |
| import java.net.URL; |
| |
| /** |
| * Utility class to determine if a service can be found on the |
| * path that might be used to create a class loader. |
| * |
| * <p><b>This is NOT part of any supported API. |
| * If you write code that depends on this, you do so at your own risk. |
| * This code and its internal interfaces are subject to change or |
| * deletion without notice.</b> |
| * |
| */ |
| // based on sun.misc.Service |
| class ServiceProxy { |
| static class ServiceConfigurationError extends Error { |
| static final long serialVersionUID = 7732091036771098303L; |
| |
| ServiceConfigurationError(String msg) { |
| super(msg); |
| } |
| } |
| |
| private static final String prefix = "META-INF/services/"; |
| |
| private static void fail(Class<?> service, String msg) |
| throws ServiceConfigurationError { |
| throw new ServiceConfigurationError(service.getName() + ": " + msg); |
| } |
| |
| private static void fail(Class<?> service, URL u, int line, String msg) |
| throws ServiceConfigurationError { |
| fail(service, u + ":" + line + ": " + msg); |
| } |
| |
| /** |
| * Parse the content of the given URL as a provider-configuration file. |
| * |
| * @param service |
| * The service class for which providers are being sought; |
| * used to construct error detail strings |
| * |
| * @param u |
| * The URL naming the configuration file to be parsed |
| * |
| * @return true if the name of a service is found |
| * |
| * @throws ServiceConfigurationError |
| * If an I/O error occurs while reading from the given URL, or |
| * if a configuration-file format error is detected |
| */ |
| private static boolean parse(Class<?> service, URL u) throws ServiceConfigurationError { |
| InputStream in = null; |
| BufferedReader r = null; |
| try { |
| in = u.openStream(); |
| r = new BufferedReader(new InputStreamReader(in, "utf-8")); |
| int lc = 1; |
| String ln; |
| while ((ln = r.readLine()) != null) { |
| int ci = ln.indexOf('#'); |
| if (ci >= 0) ln = ln.substring(0, ci); |
| ln = ln.trim(); |
| int n = ln.length(); |
| if (n != 0) { |
| if ((ln.indexOf(' ') >= 0) || (ln.indexOf('\t') >= 0)) |
| fail(service, u, lc, "Illegal configuration-file syntax"); |
| int cp = ln.codePointAt(0); |
| if (!Character.isJavaIdentifierStart(cp)) |
| fail(service, u, lc, "Illegal provider-class name: " + ln); |
| for (int i = Character.charCount(cp); i < n; i += Character.charCount(cp)) { |
| cp = ln.codePointAt(i); |
| if (!Character.isJavaIdentifierPart(cp) && (cp != '.')) |
| fail(service, u, lc, "Illegal provider-class name: " + ln); |
| } |
| return true; |
| } |
| } |
| } catch (FileNotFoundException x) { |
| return false; |
| } catch (IOException x) { |
| fail(service, ": " + x); |
| } finally { |
| try { |
| if (r != null) r.close(); |
| } catch (IOException y) { |
| fail(service, ": " + y); |
| } |
| try { |
| if (in != null) in.close(); |
| } catch (IOException y) { |
| fail(service, ": " + y); |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Return true if a description for at least one service is found in the |
| * service configuration files in the given URLs. |
| */ |
| public static boolean hasService(Class<?> service, URL[] urls) |
| throws ServiceConfigurationError { |
| for (URL url: urls) { |
| try { |
| String fullName = prefix + service.getName(); |
| URL u = new URL(url, fullName); |
| boolean found = parse(service, u); |
| if (found) |
| return true; |
| } catch (MalformedURLException e) { |
| // should not happen; ignore it if it does |
| } |
| } |
| return false; |
| } |
| } |