解决办法#1
使用定制的PluginManager
pluginManager = new JarPluginManager(this.getClass().getClassLoader());
JarPluginManager源代码:
import java.nio.file.Path;
import org.pf4j.DefaultPluginManager;
import org.pf4j.JarPluginLoader;
import org.pf4j.ManifestPluginDescriptorFinder;
import org.pf4j.PluginClassLoader;
import org.pf4j.PluginDescriptor;
import org.pf4j.PluginDescriptorFinder;
import org.pf4j.PluginLoader;
import org.pf4j.PluginManager;
/**
* see https://github.com/pf4j/pf4j/issues/249 see
* https://pf4j.org/doc/class-loading.html
*
* @author wf
*
*/
public class JarPluginManager extends DefaultPluginManager {
public static class ParentClassLoaderJarPluginLoader extends JarPluginLoader {
static ClassLoader parentClassLoader;
/**
*
* @param pluginManager
*/
public ParentClassLoaderJarPluginLoader(PluginManager pluginManager) {
super(pluginManager);
}
static PluginClassLoader pluginClassLoader;
@Override
public ClassLoader loadPlugin(Path pluginPath,
PluginDescriptor pluginDescriptor) {
if (pluginClassLoader == null) {
boolean parentFirst=true;
pluginClassLoader = new PluginClassLoader(pluginManager,
pluginDescriptor, parentClassLoader,parentFirst);
}
pluginClassLoader.addFile(pluginPath.toFile());
return pluginClassLoader;
}
}
/**
* construct me with the given classloader
* @param classLoader
*/
public JarPluginManager(ClassLoader classLoader) {
ParentClassLoaderJarPluginLoader.parentClassLoader=classLoader;
//System.setProperty("pf4j.mode", RuntimeMode.DEPLOYMENT.toString());
//System.setProperty("pf4j.mode", RuntimeMode.DEVELOPMENT.toString());
}
@Override
protected PluginLoader createPluginLoader() {
// load only jar plugins
return new ParentClassLoaderJarPluginLoader(this);
}
@Override
protected PluginDescriptorFinder createPluginDescriptorFinder() {
// read plugin descriptor from jar's manifest
return new ManifestPluginDescriptorFinder();
}
}
解决办法#2
如果未创建extensions.idx文件,则说明批注处理有问题。您可能希望修复问题的根源,但也可以尝试解决它:
@Extension
public static class MBClickHandler implements ClickHandler {
/**
* constructor with no argument
*/
public MBClickHandler() {
}
src/main/resources/META-INF/extensions.idx
com.bitplan.mb.MBClickHandlerPlugin$MBClickHandler
要检查的代码
-
extension.idx条目的正确名称
MBClickHandler ch=new MBClickHandler();
File extFile=new File("src/main/resources/META-INF/extensions.idx");
String extidx=FileUtils.readFileToString(extFile,"UTF-8");
assertEquals(extidx,ch.getClass().getName());
-
检查扩展
List<PluginWrapper> startedPlugins = pluginManager.getStartedPlugins();
for (PluginWrapper plugin : startedPlugins) {
String pluginId = plugin.getDescriptor().getPluginId();
System.out.println(String.format("Extensions added by plugin '%s':", pluginId));
Set<String> extensionClassNames = pluginManager.getExtensionClassNames(pluginId);
for (String extension : extensionClassNames) {
System.out.println(" " + extension);
}
}
