/*
* This file is part of VLCJ.
*
* VLCJ is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* VLCJ 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 for more details.
*
* You should have received a copy of the GNU General Public License
* along with VLCJ. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2009, 2010, 2011, 2012, 2013, 2014 Caprica Software Limited.
*/
package uk.co.caprica.vlcj.binding;
import java.lang.reflect.Proxy;
import java.text.MessageFormat;
import uk.co.caprica.vlcj.discovery.NativeDiscovery;
import uk.co.caprica.vlcj.logger.Logger;
import uk.co.caprica.vlcj.runtime.RuntimeUtil;
import uk.co.caprica.vlcj.version.Version;
/**
* A factory that creates interfaces to the libvlc native library.
* <p>
* For example:
*
* <pre>
* LibVlc libvlc = LibVlcFactory.factory().create();
* </pre>
*
* Or:
*
* <pre>
* LibVlc libvlc = LibVlcFactory.factory().atLeast("2.0.0").log().create();
* </pre>
*/
public class LibVlcFactory {
/**
* Help text if the native library failed to load.
*/
private static final String NATIVE_LIBRARY_HELP =
"Failed to load the native library.\n\n" +
"The error was \"{0}\".\n\n" +
"The required native libraries are named \"{1}\" and \"{2}\".\n\n" +
"In the text below <libvlc-path> represents the name of the directory containing \"{1}\" and \"{2}\"...\n\n" +
"There are a number of different ways to specify where to find the native libraries:\n" +
" 1. Include NativeLibrary.addSearchPath(\"{3}\", \"<libvlc-path>\"); at the start of your application code.\n" +
" 2. Include System.setProperty(\"jna.library.path\", \"<libvlc-path>\"); at the start of your application code.\n" +
" 3. Specify -Djna.library.path=<libvlc-path> on the command-line when starting your application.\n" +
" 4. Add <libvlc-path> to the system search path (and reboot).\n\n" +
"If this still does not work, then it may be necessary to explicitly add the native library directory to the operating\n" +
"system configuration - e.g. on Linux this might mean setting the LD_LIBRARY_PATH environment variable, or adding\n" +
"configuration to the \"/etc/ld.so.conf\" file or the \"/etc/ld.so.conf.d\" directory. Of these options, setting\n" +
"LD_LIBRARY_PATH is the only one that would not require root privileges.\n\n" +
"Finally, it is not possible to mix CPU architectures - it is not possible for a 64-bit Java Virtual Machine to load\n" +
"32-bit native libraries.\n\n" +
"More information may be available in the log, specify -Dvlcj.log=DEBUG on the command-line when starting your application.\n";
/**
* True if the access to the native library should be synchronised.
*/
private boolean synchronise;
/**
* True if the access to the native library should be logged.
*/
private boolean log;
/**
* At least this native library version is required.
*/
private Version requiredVersion;
/**
* Component used to search for libvlc native libraries.
*/
private NativeDiscovery discovery;
/**
* Private constructor prevents direct instantiation by others.
*/
private LibVlcFactory() {
}
/**
* Create a new factory instance
*
* @return factory
*/
public static LibVlcFactory factory() {
return new LibVlcFactory();
}
/**
* Request that the libvlc native library instance be synchronised.
*
* @return factory
*/
public LibVlcFactory synchronise() {
this.synchronise = true;
return this;
}
/**
* Request that the libvlc native library instance be logged.
*
* @return factory
*/
public LibVlcFactory log() {
this.log = true;
return this;
}
/**
* Request that the libvlc native library be of at least a particular version.
*
* @param version required version
* @return factory
*/
public LibVlcFactory atLeast(String version) {
this.requiredVersion = new Version(version);
return this;
}
/**
* Request that automatic discovery of the native libraries be tried.
*
* @param discovery discovery
* @return factory
*/
public LibVlcFactory discovery(NativeDiscovery discovery) {
this.discovery = discovery;
return this;
}
/**
* Create a new libvlc native library instance.
*
* @return native library instance
* @throws RuntimeException if a minimum version check was specified and failed
*/
public LibVlc create() {
// Invoke discovery?
if(discovery != null) {
discovery.discover();
}
// Synchronised or not...
try {
LibVlc instance = synchronise ? LibVlc.SYNC_INSTANCE : LibVlc.INSTANCE;
// Logged...
if(log) {
instance = (LibVlc)Proxy.newProxyInstance(LibVlc.class.getClassLoader(), new Class<?>[] {LibVlc.class}, new LoggingProxy(instance));
}
String nativeVersion = instance.libvlc_get_version();
Logger.info("vlc: {}, changeset {}", nativeVersion, LibVlc.INSTANCE.libvlc_get_changeset());
Logger.info("libvlc: {}", getNativeLibraryPath(instance));
if(requiredVersion != null) {
Version actualVersion;
try {
actualVersion = new Version(nativeVersion);
}
catch(Exception e) {
Logger.error("Unable to parse native library version {} because of {}", nativeVersion, e);
actualVersion = null;
}
if(actualVersion != null) {
if(!actualVersion.atLeast(requiredVersion)) {
Logger.fatal("This version of vlcj requires version {} or later of libvlc, found too old version {}", requiredVersion, actualVersion);
throw new LibVlcOutOfDateException(requiredVersion, actualVersion);
}
}
else {
Logger.fatal("Unable to check the native library version '{}'", nativeVersion);
throw new RuntimeException("Unable to check the native library version " + nativeVersion);
}
}
return instance;
}
catch(UnsatisfiedLinkError e) {
Logger.error("Failed to load native library");
String msg = MessageFormat.format(NATIVE_LIBRARY_HELP, new Object[] {e.getMessage(), RuntimeUtil.getLibVlcName(), RuntimeUtil.getLibVlcCoreName(), RuntimeUtil.getLibVlcLibraryName()});
throw new RuntimeException(msg);
}
}
/**
* Parse out the complete file path of the native library.
* <p>
* This depends on the format of the toString() of the JNA implementation class.
*
* @param library native library instance
* @return native library path, or simply the toString of the instance if the path could not be parsed out
*/
private static String getNativeLibraryPath(Object library) {
String s = library.toString();
int start = s.indexOf('<');
if(start != -1) {
start ++ ;
int end = s.indexOf('@', start);
if(end != -1) {
s = s.substring(start, end);
return s;
}
}
return s;
}
}