130 lines
3.3 KiB
Java
130 lines
3.3 KiB
Java
package org.gcube.data.analysis.wps.repository;
|
|
|
|
import static java.nio.file.StandardWatchEventKinds.ENTRY_CREATE;
|
|
import static java.nio.file.StandardWatchEventKinds.OVERFLOW;
|
|
|
|
import java.io.IOException;
|
|
import java.lang.reflect.Method;
|
|
import java.net.URL;
|
|
import java.net.URLClassLoader;
|
|
import java.nio.file.FileSystems;
|
|
import java.nio.file.Path;
|
|
import java.nio.file.Paths;
|
|
import java.nio.file.WatchEvent;
|
|
import java.nio.file.WatchKey;
|
|
import java.nio.file.WatchService;
|
|
|
|
import org.slf4j.Logger;
|
|
import org.slf4j.LoggerFactory;
|
|
|
|
public final class AlgorithmUpdater {
|
|
|
|
private static final Logger log = LoggerFactory.getLogger(AlgorithmUpdater.class);
|
|
|
|
private String algorithmDirectory;
|
|
|
|
private boolean mustUpdate = false;
|
|
|
|
private WatcherThread watcherThread = null;
|
|
|
|
public AlgorithmUpdater(String algorithmDirectory) {
|
|
super();
|
|
this.algorithmDirectory = algorithmDirectory;
|
|
}
|
|
|
|
protected synchronized boolean mustUpdate(){
|
|
return mustUpdate;
|
|
}
|
|
|
|
protected synchronized void reset(){
|
|
mustUpdate = false;
|
|
}
|
|
|
|
public boolean isStarted(){
|
|
return watcherThread!=null;
|
|
}
|
|
|
|
protected void startWhatcher(){
|
|
watcherThread = new WatcherThread(Thread.currentThread().getContextClassLoader(), algorithmDirectory);
|
|
watcherThread.start();
|
|
}
|
|
|
|
private class WatcherThread extends Thread {
|
|
|
|
private WatchService watcher;
|
|
private ClassLoader loader;
|
|
private Path dir;
|
|
|
|
public WatcherThread(ClassLoader loader, String algorithmDirectory) {
|
|
super();
|
|
try {
|
|
watcher = FileSystems.getDefault().newWatchService();
|
|
this.loader = loader;
|
|
//TODO: change with something from configuration
|
|
dir = Paths.get(algorithmDirectory);
|
|
dir.register(watcher, ENTRY_CREATE);
|
|
} catch (IOException e) {
|
|
throw new RuntimeException(e);
|
|
}
|
|
}
|
|
|
|
@SuppressWarnings("unchecked")
|
|
public void run(){
|
|
for (;;) {
|
|
|
|
// wait for key to be signaled
|
|
WatchKey key;
|
|
try {
|
|
key = watcher.take();
|
|
} catch (InterruptedException x) {
|
|
return;
|
|
}
|
|
|
|
for (WatchEvent<?> event: key.pollEvents()) {
|
|
WatchEvent.Kind<?> kind = event.kind();
|
|
|
|
// This key is registered only
|
|
// for ENTRY_CREATE events,
|
|
// but an OVERFLOW event can
|
|
// occur regardless if events
|
|
// are lost or discarded.
|
|
if (kind == OVERFLOW) {
|
|
continue;
|
|
}
|
|
|
|
// The filename is the
|
|
// context of the event.
|
|
WatchEvent<Path> ev = (WatchEvent<Path>)event;
|
|
Path filename = ev.context();
|
|
if (filename.toString().endsWith(".jar")){
|
|
try{
|
|
final Class<URLClassLoader> sysclass = URLClassLoader.class;
|
|
// TODO some kind of a hack. Need to invent better solution.
|
|
final Method method = sysclass.getDeclaredMethod("addURL", new Class[] { URL.class });
|
|
method.setAccessible(true);
|
|
method.invoke(loader, new URL[] { dir.resolve(filename).toFile().toURI().toURL() });
|
|
log.info("filename added is {} in loader {}",filename, loader.getClass().getName());
|
|
mustUpdate = true;
|
|
}catch(Exception e){
|
|
log.error("filename {} cannot be added to classpath",e,filename);
|
|
}
|
|
} else log.info("filename {} is not a jar",filename);
|
|
|
|
}
|
|
|
|
boolean valid = key.reset();
|
|
if (!valid) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
protected void shutdown(){
|
|
if (isStarted()){
|
|
//TODO : kill the watcherThread
|
|
watcherThread = null;
|
|
}
|
|
}
|
|
}
|