libjava/classpath/ChangeLog.gcj:
2007-05-31 Matthias Klose <doko@ubuntu.com> * javax/management/NotificationBroadcasterSupport.java (getNotificationInfo): Add cast. * native/jni/qt-peer/Makefile.am (AM_CXXFLAGS): Add libstdc++ include directories. * native/jni/qt-peer/Makefile.in: Regenerate. libjava/ChangeLog: 2007-06-03 Matthias Klose <doko@ubuntu.com> * java/io/natFileWin32.cc (setFilePermissions): New (stub only). _access: Handle EXEC query, stub only. 2007-06-03 Matthias Klose <doko@ubuntu.com> Merged from classpath: * gnu/java/nio/SelectorProviderImpl.java: Whitespace merge. * java/lang/System.java(inheritedChannel): New. * java/lang/Character.java: Remove stray`;'. * java/net/MulticastSocket.java: Merged. * java/text/DateFormatSymbols.java(getInstance): New, comment updates. * java/text/Collator.java(getInstance): Merged. * java/util/Calendar.java: New attributes ALL_STYLES, SHORT, LONG. getDisplayName, getDisplayNames: New. * java/util/logging/Logger.java: Merged. * Regenerate .class and .h files. 2007-06-03 Matthias Klose <doko@ubuntu.com> * java/io/File.java: Merge with classpath-0.95, new method setFilePermissions, new attribute EXEC. * java/io/natFilePosix.cc (setFilePermissions): New. _access: Handle EXEC query. * classpath/lib/java/io/File.class, java/io/File.h: Regenerate. 2007-06-03 Matthias Klose <doko@ubuntu.com> Imported GNU Classpath 0.95. * classpath/Makefile.in, classpath/native/jni/midi-dssi/Makefile.in, classpath/native/jni/classpath/Makefile.in, classpath/native/jni/Makefile.in, classpath/native/jni/gconf-peer/Makefile.in, classpath/native/jni/java-io/Makefile.in, classpath/native/jni/native-lib/Makefile.in, classpath/native/jni/java-util/Makefile.in, classpath/native/jni/midi-alsa/Makefile.in, classpath/native/jni/java-lang/Makefile.in, classpath/native/jni/java-nio/Makefile.in, classpath/native/jni/java-net/Makefile.in, classpath/native/jni/xmlj/Makefile.in, classpath/native/jni/qt-peer/Makefile.in, classpath/native/jni/gtk-peer/Makefile.in, classpath/native/Makefile.in, classpath/native/jawt/Makefile.in, classpath/native/fdlibm/Makefile.in, classpath/native/plugin/Makefile.in, classpath/resource/Makefile.in, classpath/scripts/Makefile.in, classpath/tools/Makefile.in, classpath/doc/Makefile.in, classpath/doc/api/Makefile.in, classpath/lib/Makefile.in, classpath/external/Makefile.in, classpath/external/jsr166/Makefile.in, classpath/external/sax/Makefile.in, classpath/external/w3c_dom/Makefile.in, classpath/external/relaxngDatatype/Makefile.in, classpath/include/Makefile.in, classpath/examples/Makefile.in: Regenerate. * classpath/config.guess, classpath/config.sub, classpath/ltmain.sh : Update. * classpath/configure, classpath/depcomp, classpath/missing, classpath/aclocal.m4, classpath/install-sh: Regenerate. * gnu/classpath/Configuration.java (CLASSPATH_VERSION): Now 0.95. * sources.am: Regenerate. * Makefile.in: Regenerate. * Update the .class files and generated CNI header files, add new .class and generated CNI header files. * Remove generated files for removed java source files: classpath/gnu/java/net/BASE64.java, classpath/gnu/java/security/util/Base64.java, classpath/gnu/java/awt/peer/gtk/GThreadMutex.java, classpath/gnu/java/awt/peer/gtk/GThreadNativeMethodRunner.java, classpath/gnu/java/awt/font/autofit/Scaler.java, classpath/gnu/classpath/jdwp/util/Value.java, classpath/gnu/javax/net/ssl/Base64.java. * Remove empty directories. * Makefile.am(nat_source_files): Add natVMOperatingSystemMXBeanImpl.cc. * java/lang/Class.java(setAccessible): Merge from classpath. * java/util/Locale.java: Remove. * gnu/java/lang/management/VMOperatingSystemMXBeanImpl.java, gnu/java/lang/management/natVMOperatingSystemMXBeanImpl.cc: New. * gcj/javaprims.h: Update class declarations. * scripts/classes.pl: Update usage. * HACKING: Mention to build all peers. From-SVN: r125302
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274
libjava/classpath/java/util/ServiceLoader.java
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274
libjava/classpath/java/util/ServiceLoader.java
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/* ServiceLoader.java -- Allows loading of plug-in services.
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Copyright (C) 2006, 2007 Free Software Foundation
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This file is part of GNU Classpath.
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GNU Classpath is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GNU Classpath is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Classpath; see the file COPYING. If not, write to the
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301 USA.
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Linking this library statically or dynamically with other modules is
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making a combined work based on this library. Thus, the terms and
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conditions of the GNU General Public License cover the whole
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combination.
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As a special exception, the copyright holders of this library give you
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permission to link this library with independent modules to produce an
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executable, regardless of the license terms of these independent
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modules, and to copy and distribute the resulting executable under
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terms of your choice, provided that you also meet, for each linked
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independent module, the terms and conditions of the license of that
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module. An independent module is a module which is not derived from
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or based on this library. If you modify this library, you may extend
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this exception to your version of the library, but you are not
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obligated to do so. If you do not wish to do so, delete this
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exception statement from your version. */
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package java.util;
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import gnu.classpath.ServiceFactory;
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/**
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* <p>
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* Facilities for loading service providers. A service is
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* defined by a set of interfaces or abstract classes, and
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* a service provider gives a concrete implementation of this.
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* Service providers may be installed as part of the runtime
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* environment using JAR files in the extension directories,
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* or may be simply supplied on the classpath.
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* </p>
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* <p>
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* In terms of loading a service, the service is defined by
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* a single interface or abstract class which the provider
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* implements. This may not constitute the entire service,
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* but is simply a mechanism by which a provider of the
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* service can be loaded and its capabilities determined.
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* The variety of possible services means that no more
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* requirements are made of the service provider other than
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* that it must have an accessible zero argument constructor
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* in order to allow an instance to be created.
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* </p>
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* <p>
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* Service providers are listed in a file named after the
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* service type in the directory <code>META-INF/services</code>.
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* The file contains a list of classes, and must be encoded
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* using UTF-8. Whitespace is ignored. Comments can be
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* included by using a <code>'#'</code> prefix; anything occurring
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* on the same line after this symbol is ignored. Duplicate classes
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* are ignored.
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* </p>
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* <p>
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* The classes are loaded using the same classloader that was
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* queried in order to locate the configuration file. As a result,
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* the providers do not need to reside in the same JAR file as the
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* resource; they merely have to be accessible to this classloader,
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* which may differ from the one that loaded the file itself.
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* </p>
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* <p>
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* Providers are located and instantiated lazily, as calls to the
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* {@link #iterator()} are made. Providers are cached, and those in
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* the cache are returned first. The cache may be cleared by calling
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* {@link #reload()}. Service loaders always execute in the security
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* context of the caller, so ideally calls should be made from a trusted
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* source.
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* </p>
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* <p>
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* Note that this class is not thread-safe, and that strange errors may
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* occur as the result of the use of remote URLs occurring on the classpath,
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* which lead to erroneous web pages.
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* </p>
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*
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* @author Andrew John Hughes (gnu_andrew@member.fsf.org)
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* @since 1.6
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*/
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public final class ServiceLoader<S>
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implements Iterable<S>
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{
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/**
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* The class of the service provider.
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*/
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private Class<S> spi;
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/**
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* The class loader for the service provider.
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*/
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private ClassLoader loader;
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/**
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* The cache of service providers.
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*/
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private List<S> cache;
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/**
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* The {@link gnu.classpath.ServiceFactory} iterator
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* from which providers are obtained.
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*/
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private Iterator<S> serviceIt;
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/**
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* Constructs a new {@link ServiceLoader} with
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* the specified provider and class loader.
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*
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* @param spi the service to load.
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* @param loader the class loader to use.
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*/
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private ServiceLoader(Class<S> spi, ClassLoader loader)
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{
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this.spi = spi;
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this.loader = loader;
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cache = new ArrayList<S>();
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}
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/**
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* Lazily loads the available providers. The iterator first returns
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* providers from the cache, in instantiation order, followed by any
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* remaining providers, which are added to the cache after loading.
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* The actual loading and parsing of the configuration file takes
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* place in the {@link Iterator#hasNext()} and {@link Iterator#next()}
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* methods, which means that they may result in a
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* {@link ServiceConfigurationError} being thrown. If such an error
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* does occur, subsequent invocations will attempt to recover.
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* The {@link remove()} method is not supported and instead throws
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* an {@link UnsupportedOperationException}.
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*
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* @return an iterator that lazily loads service providers.
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*/
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public Iterator<S> iterator()
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{
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return new Iterator<S>()
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{
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/**
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* The cache iterator.
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*/
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private Iterator<S> cacheIt = cache.iterator();
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public boolean hasNext()
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{
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if (cacheIt.hasNext())
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return true;
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if (serviceIt == null)
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serviceIt =
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ServiceFactory.lookupProviders(spi, loader, true);
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return serviceIt.hasNext();
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}
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public S next()
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{
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if (cacheIt.hasNext())
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return cacheIt.next();
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if (serviceIt == null)
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serviceIt =
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ServiceFactory.lookupProviders(spi, loader, true);
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S nextService = serviceIt.next();
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cache.add(nextService);
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return nextService;
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}
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public void remove()
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{
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throw new UnsupportedOperationException();
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}
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};
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}
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/**
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* Creates a new service loader for the given service,
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* using the context class loader of the current thread.
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* This is equivalent to calling <code>ServiceLoader.load(service,
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* Thread.currentThread().getContextClassLoader())</code>.
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*
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* @param service the interface or abstract class that represents
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* the service.
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* @return a new {@link ServiceLoader} instance.
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*/
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public static <S> ServiceLoader<S> load(Class<S> service)
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{
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return load(service,
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Thread.currentThread().getContextClassLoader());
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}
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/**
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* Creates a new service loader for the given service,
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* using the specified class loader. The class loader is
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* used to access the configuration file and the service
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* provider instances themselves. If the loader is
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* <code>null</code>, the system class loader (or, if
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* this is also <code>null</code>, the bootstrap class
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* loader).
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*
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* @param service the interface or abstract class that represents
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* the service.
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* @param loader the class loader used to load the configuration
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* file and service providers.
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* @return a new {@link ServiceLoader} instance.
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*/
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public static <S> ServiceLoader<S> load(Class<S> service,
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ClassLoader loader)
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{
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if (loader == null)
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loader = ClassLoader.getSystemClassLoader();
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return new ServiceLoader(service, loader);
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}
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/**
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* Creates a new service loader for the given service,
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* using the extension class loader. If the extension
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* class loader can not be found, the system class loader
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* is used (or, if this is <code>null</code>, the
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* bootstrap class loader). The primary use of this method
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* is to only obtain installed services, ignoring any which
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* may appear on the classpath. This is equivalent to calling
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* <code>load(service, extClassLoader)</code> where
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* <code>extClassLoader</code> is the extension class loader
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* (or <code>null</code> if this is unavailable).
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*
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* @param service the interface or abstract class that represents
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* the service.
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* @return a new {@link ServiceLoader} instance.
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*/
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public static <S> ServiceLoader<S> loadInstalled(Class<S> service)
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{
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/* We expect the extension class loader to be the parent
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* of the system class loader, as in
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* ClassLoader.getDefaultSystemClassLoader() */
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return load(service,
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ClassLoader.getSystemClassLoader().getParent());
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}
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/**
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* Clears the cache of the provider, so that all providers
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* are again read from the configuration file and instantiated.
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*/
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public void reload()
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{
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cache.clear();
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}
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/**
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* Returns a textual representation of this
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* {@link ServiceLoader}.
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*
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* @return a textual representation of the
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* service loader.
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*/
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public String toString()
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{
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return getClass().getName() +
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"[spi=" + spi +
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",loader=" + loader +
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"]";
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}
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}
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