Relax Plugin construction (remove dependency on PluginWrapper)

6 files changed, 385 insertions, 314 deletions

diff --git a/pf4j/src/main/java/org/pf4j/DefaultPluginFactory.java b/pf4j/src/main/java/org/pf4j/DefaultPluginFactory.java
index 2f55cab..db86006 100644
--- a/pf4j/src/main/java/org/pf4j/DefaultPluginFactory.java
+++ b/pf4j/src/main/java/org/pf4j/DefaultPluginFactory.java
@@ -23,18 +23,16 @@ import java.lang.reflect.Modifier;
 
 /**
  * The default implementation for {@link PluginFactory}.
- * It uses {@link Class#newInstance()} method.
+ * It uses {@link Constructor#newInstance(Object...)} method.
  *
  * @author Decebal Suiu
  */
 public class DefaultPluginFactory implements PluginFactory {
 
-    private static final Logger log = LoggerFactory.getLogger(DefaultPluginFactory.class);
+    protected static final Logger log = LoggerFactory.getLogger(DefaultPluginFactory.class);
 
     /**
-     * Creates a plugin instance. If an error occurs than that error is logged and the method returns null.
-     * @param pluginWrapper
-     * @return
+     * Creates a plugin instance. If an error occurs than that error is logged and the method returns {@code null}.
      */
     @Override
     public Plugin create(final PluginWrapper pluginWrapper) {
@@ -58,10 +56,21 @@ public class DefaultPluginFactory implements PluginFactory {
             return null;
         }
 
-        // create the plugin instance
+        return createInstance(pluginClass, pluginWrapper);
+    }
+
+    /**
+     * Creates a plugin instance. If an error occurs than that error is logged and the method returns {@code null}.
+     */
+    protected Plugin createInstance(Class<?> pluginClass, PluginWrapper pluginWrapper) {
         try {
-            Constructor<?> constructor = pluginClass.getConstructor(PluginWrapper.class);
-            return (Plugin) constructor.newInstance(pluginWrapper);
+            try {
+                Constructor<?> constructor = pluginClass.getConstructor(PluginWrapper.class);
+                return (Plugin) constructor.newInstance(pluginWrapper);
+            } catch (NoSuchMethodException e) {
+                Constructor<?> constructor = pluginClass.getConstructor();
+                return (Plugin) constructor.newInstance();
+            }
         } catch (Exception e) {
             log.error(e.getMessage(), e);
         }
diff --git a/pf4j/src/main/java/org/pf4j/Plugin.java b/pf4j/src/main/java/org/pf4j/Plugin.java
index e3dd449..29a36ad 100644
--- a/pf4j/src/main/java/org/pf4j/Plugin.java
+++ b/pf4j/src/main/java/org/pf4j/Plugin.java
@@ -34,13 +34,17 @@ public class Plugin {
     /**
      * Wrapper of the plugin.
      */
+    @Deprecated
     protected PluginWrapper wrapper;
 
     /**
      * Constructor to be used by plugin manager for plugin instantiation.
      * Your plugins have to provide constructor with this exact signature to
      * be successfully loaded by manager.
+     * @deprecated Use application custom {@code PluginContext} instead of {@code PluginWrapper}.
+     * See demo for more details.
      */
+    @Deprecated
     public Plugin(final PluginWrapper wrapper) {
         if (wrapper == null) {
             throw new IllegalArgumentException("Wrapper cannot be null");
@@ -49,9 +53,13 @@ public class Plugin {
         this.wrapper = wrapper;
     }
 
+    public Plugin() {
+    }
+
     /**
      * Retrieves the wrapper of this plug-in.
      */
+    @Deprecated
     public final PluginWrapper getWrapper() {
         return wrapper;
     }
diff --git a/pf4j/src/main/java/org/pf4j/SecurePluginManagerWrapper.java b/pf4j/src/main/java/org/pf4j/SecurePluginManagerWrapper.java
index f55b1e6..ee2d681 100644
--- a/pf4j/src/main/java/org/pf4j/SecurePluginManagerWrapper.java
+++ b/pf4j/src/main/java/org/pf4j/SecurePluginManagerWrapper.java
@@ -1,305 +1,308 @@
-package org.pf4j;

-

-import java.nio.file.Path;

-import java.util.ArrayList;

-import java.util.Arrays;

-import java.util.Collections;

-import java.util.List;

-import java.util.Set;

-import java.util.stream.Collectors;

-

-/**

- * Use this class to wrap the original plugin manager to prevent full access from within plugins.

- * Override AbstractPluginManager.createPluginWrapper to use this class

- * @author Wolfram Haussig

- *

- */

-public class SecurePluginManagerWrapper implements PluginManager {

-

-    private static final String PLUGIN_PREFIX = "Plugin ";

-    /**

-     * the current plugin

-     */

-    private String currentPluginId;

-    /**

-     * the original plugin manager

-     */

-    private PluginManager original;

-

-    /**

-     * The registered {@link PluginStateListener}s.

-     */

-    protected List<PluginStateListener> pluginStateListeners = new ArrayList<>();

-    /**

-     * wrapper for pluginStateListeners

-     */

-    private PluginStateListenerWrapper listenerWrapper = new PluginStateListenerWrapper();

-

-    /**

-     * constructor

-     * @param original the original plugin manager

-     * @param currentPlugin the current pluginId

-     */

-    public SecurePluginManagerWrapper(PluginManager original, String currentPluginId) {

-        this.original = original;

-        this.currentPluginId = currentPluginId;

-    }

-

-    @Override

-    public boolean isDevelopment() {

-        return original.isDevelopment();

-    }

-

-    @Override

-    public boolean isNotDevelopment() {

-        return original.isNotDevelopment();

-    }

-

-    @Override

-    public List<PluginWrapper> getPlugins() {

-        return Arrays.asList(getPlugin(currentPluginId));

-    }

-

-    @Override

-    public List<PluginWrapper> getPlugins(PluginState pluginState) {

-        return getPlugins().stream().filter(p -> p.getPluginState() == pluginState).collect(Collectors.toList());

-    }

-

-    @Override

-    public List<PluginWrapper> getResolvedPlugins() {

-        return getPlugins().stream().filter(p -> p.getPluginState().ordinal() >= PluginState.RESOLVED.ordinal()).collect(Collectors.toList());

-    }

-

-    @Override

-    public List<PluginWrapper> getUnresolvedPlugins() {

-        return Collections.emptyList();

-    }

-

-    @Override

-    public List<PluginWrapper> getStartedPlugins() {

-        return getPlugins(PluginState.STARTED);

-    }

-

-    @Override

-    public PluginWrapper getPlugin(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.getPlugin(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getPlugin for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public void loadPlugins() {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute loadPlugins!");

-    }

-

-    @Override

-    public String loadPlugin(Path pluginPath) {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute loadPlugin!");

-    }

-

-    @Override

-    public void startPlugins() {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute startPlugins!");

-    }

-

-    @Override

-    public PluginState startPlugin(String pluginId) {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute startPlugin!");

-    }

-

-    @Override

-    public void stopPlugins() {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute stopPlugins!");

-    }

-

-    @Override

-    public PluginState stopPlugin(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.stopPlugin(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute stopPlugin for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public void unloadPlugins() {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute unloadPlugins!");

-    }

-

-    @Override

-    public boolean unloadPlugin(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.unloadPlugin(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute unloadPlugin for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public boolean disablePlugin(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.disablePlugin(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute disablePlugin for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public boolean enablePlugin(String pluginId) {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute enablePlugin!");

-    }

-

-    @Override

-    public boolean deletePlugin(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.deletePlugin(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute deletePlugin for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public ClassLoader getPluginClassLoader(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.getPluginClassLoader(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getPluginClassLoader for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public List<Class<?>> getExtensionClasses(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.getExtensionClasses(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensionClasses for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public <T> List<Class<? extends T>> getExtensionClasses(Class<T> type) {

-        return getExtensionClasses(type, currentPluginId);

-    }

-

-    @Override

-    public <T> List<Class<? extends T>> getExtensionClasses(Class<T> type, String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.getExtensionClasses(type, pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensionClasses for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public <T> List<T> getExtensions(Class<T> type) {

-        return getExtensions(type, currentPluginId);

-    }

-

-    @Override

-    public <T> List<T> getExtensions(Class<T> type, String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.getExtensions(type, pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensions for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public List<?> getExtensions(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.getExtensions(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensions for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public Set<String> getExtensionClassNames(String pluginId) {

-        if (currentPluginId.equals(pluginId)) {

-            return original.getExtensionClassNames(pluginId);

-        } else {

-            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensionClassNames for foreign pluginId!");

-        }

-    }

-

-    @Override

-    public ExtensionFactory getExtensionFactory() {

-        return original.getExtensionFactory();

-    }

-

-    @Override

-    public RuntimeMode getRuntimeMode() {

-        return original.getRuntimeMode();

-    }

-

-    @Override

-    public PluginWrapper whichPlugin(Class<?> clazz) {

-        ClassLoader classLoader = clazz.getClassLoader();

-        PluginWrapper plugin = getPlugin(currentPluginId);

-        if (plugin.getPluginClassLoader() == classLoader) {

-            return plugin;

-        }

-        return null;

-    }

-

-    @Override

-    public void addPluginStateListener(PluginStateListener listener) {

-        if (pluginStateListeners.isEmpty()) {

-            this.original.addPluginStateListener(listenerWrapper);

-        }

-        pluginStateListeners.add(listener);

-    }

-

-    @Override

-    public void removePluginStateListener(PluginStateListener listener) {

-        pluginStateListeners.remove(listener);

-        if (pluginStateListeners.isEmpty()) {

-            this.original.removePluginStateListener(listenerWrapper);

-        }

-    }

-

-    @Override

-    public void setSystemVersion(String version) {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute setSystemVersion!");

-    }

-

-    @Override

-    public String getSystemVersion() {

-        return original.getSystemVersion();

-    }

-

-    @Override

-    public Path getPluginsRoot() {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getPluginsRoot!");

-    }

-

-    @Override

-    public List<Path> getPluginsRoots() {

-        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getPluginsRoots!");

-    }

-

-    @Override

-    public VersionManager getVersionManager() {

-        return original.getVersionManager();

-    }

-

-    /**

-     * Wrapper for PluginStateListener events. will only propagate events if they match the current pluginId

-     * @author Wolfram Haussig

-     *

-     */

-    private class PluginStateListenerWrapper implements PluginStateListener {

-

-        @Override

-        public void pluginStateChanged(PluginStateEvent event) {

-            if (event.getPlugin().getPluginId().equals(currentPluginId)) {

-                for (PluginStateListener listener : pluginStateListeners) {

-                    listener.pluginStateChanged(event);

-                }

-            }

-        }

-

-    }

-}

+package org.pf4j;
+
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * Use this class to wrap the original plugin manager to prevent full access from within plugins.
+ * Override AbstractPluginManager.createPluginWrapper to use this class.
+ * @deprecated Use application custom {@code PluginContext} instead of {@code PluginWrapper} to communicate with {@link Plugin}.
+ * See demo for more details.
+ *
+ * @author Wolfram Haussig
+ */
+@Deprecated()
+public class SecurePluginManagerWrapper implements PluginManager {
+
+    private static final String PLUGIN_PREFIX = "Plugin ";
+    /**
+     * the current plugin
+     */
+    private String currentPluginId;
+    /**
+     * the original plugin manager
+     */
+    private PluginManager original;
+
+    /**
+     * The registered {@link PluginStateListener}s.
+     */
+    protected List<PluginStateListener> pluginStateListeners = new ArrayList<>();
+    /**
+     * wrapper for pluginStateListeners
+     */
+    private PluginStateListenerWrapper listenerWrapper = new PluginStateListenerWrapper();
+
+    /**
+     * constructor
+     * @param original the original plugin manager
+     * @param currentPluginId the current pluginId
+     */
+    public SecurePluginManagerWrapper(PluginManager original, String currentPluginId) {
+        this.original = original;
+        this.currentPluginId = currentPluginId;
+    }
+
+    @Override
+    public boolean isDevelopment() {
+        return original.isDevelopment();
+    }
+
+    @Override
+    public boolean isNotDevelopment() {
+        return original.isNotDevelopment();
+    }
+
+    @Override
+    public List<PluginWrapper> getPlugins() {
+        return Arrays.asList(getPlugin(currentPluginId));
+    }
+
+    @Override
+    public List<PluginWrapper> getPlugins(PluginState pluginState) {
+        return getPlugins().stream().filter(p -> p.getPluginState() == pluginState).collect(Collectors.toList());
+    }
+
+    @Override
+    public List<PluginWrapper> getResolvedPlugins() {
+        return getPlugins().stream().filter(p -> p.getPluginState().ordinal() >= PluginState.RESOLVED.ordinal()).collect(Collectors.toList());
+    }
+
+    @Override
+    public List<PluginWrapper> getUnresolvedPlugins() {
+        return Collections.emptyList();
+    }
+
+    @Override
+    public List<PluginWrapper> getStartedPlugins() {
+        return getPlugins(PluginState.STARTED);
+    }
+
+    @Override
+    public PluginWrapper getPlugin(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.getPlugin(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getPlugin for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public void loadPlugins() {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute loadPlugins!");
+    }
+
+    @Override
+    public String loadPlugin(Path pluginPath) {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute loadPlugin!");
+    }
+
+    @Override
+    public void startPlugins() {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute startPlugins!");
+    }
+
+    @Override
+    public PluginState startPlugin(String pluginId) {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute startPlugin!");
+    }
+
+    @Override
+    public void stopPlugins() {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute stopPlugins!");
+    }
+
+    @Override
+    public PluginState stopPlugin(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.stopPlugin(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute stopPlugin for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public void unloadPlugins() {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute unloadPlugins!");
+    }
+
+    @Override
+    public boolean unloadPlugin(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.unloadPlugin(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute unloadPlugin for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public boolean disablePlugin(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.disablePlugin(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute disablePlugin for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public boolean enablePlugin(String pluginId) {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute enablePlugin!");
+    }
+
+    @Override
+    public boolean deletePlugin(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.deletePlugin(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute deletePlugin for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public ClassLoader getPluginClassLoader(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.getPluginClassLoader(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getPluginClassLoader for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public List<Class<?>> getExtensionClasses(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.getExtensionClasses(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensionClasses for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public <T> List<Class<? extends T>> getExtensionClasses(Class<T> type) {
+        return getExtensionClasses(type, currentPluginId);
+    }
+
+    @Override
+    public <T> List<Class<? extends T>> getExtensionClasses(Class<T> type, String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.getExtensionClasses(type, pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensionClasses for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public <T> List<T> getExtensions(Class<T> type) {
+        return getExtensions(type, currentPluginId);
+    }
+
+    @Override
+    public <T> List<T> getExtensions(Class<T> type, String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.getExtensions(type, pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensions for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public List<?> getExtensions(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.getExtensions(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensions for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public Set<String> getExtensionClassNames(String pluginId) {
+        if (currentPluginId.equals(pluginId)) {
+            return original.getExtensionClassNames(pluginId);
+        } else {
+            throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getExtensionClassNames for foreign pluginId!");
+        }
+    }
+
+    @Override
+    public ExtensionFactory getExtensionFactory() {
+        return original.getExtensionFactory();
+    }
+
+    @Override
+    public RuntimeMode getRuntimeMode() {
+        return original.getRuntimeMode();
+    }
+
+    @Override
+    public PluginWrapper whichPlugin(Class<?> clazz) {
+        ClassLoader classLoader = clazz.getClassLoader();
+        PluginWrapper plugin = getPlugin(currentPluginId);
+        if (plugin.getPluginClassLoader() == classLoader) {
+            return plugin;
+        }
+        return null;
+    }
+
+    @Override
+    public void addPluginStateListener(PluginStateListener listener) {
+        if (pluginStateListeners.isEmpty()) {
+            this.original.addPluginStateListener(listenerWrapper);
+        }
+        pluginStateListeners.add(listener);
+    }
+
+    @Override
+    public void removePluginStateListener(PluginStateListener listener) {
+        pluginStateListeners.remove(listener);
+        if (pluginStateListeners.isEmpty()) {
+            this.original.removePluginStateListener(listenerWrapper);
+        }
+    }
+
+    @Override
+    public void setSystemVersion(String version) {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute setSystemVersion!");
+    }
+
+    @Override
+    public String getSystemVersion() {
+        return original.getSystemVersion();
+    }
+
+    @Override
+    public Path getPluginsRoot() {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getPluginsRoot!");
+    }
+
+    @Override
+    public List<Path> getPluginsRoots() {
+        throw new IllegalAccessError(PLUGIN_PREFIX + currentPluginId + " tried to execute getPluginsRoots!");
+    }
+
+    @Override
+    public VersionManager getVersionManager() {
+        return original.getVersionManager();
+    }
+
+    /**
+     * Wrapper for PluginStateListener events. will only propagate events if they match the current pluginId
+     * @author Wolfram Haussig
+     *
+     */
+    private class PluginStateListenerWrapper implements PluginStateListener {
+
+        @Override
+        public void pluginStateChanged(PluginStateEvent event) {
+            if (event.getPlugin().getPluginId().equals(currentPluginId)) {
+                for (PluginStateListener listener : pluginStateListeners) {
+                    listener.pluginStateChanged(event);
+                }
+            }
+        }
+
+    }
+}
diff --git a/pf4j/src/test/java/org/pf4j/DefaultPluginFactoryTest.java b/pf4j/src/test/java/org/pf4j/DefaultPluginFactoryTest.java
index 3107083..c453e38 100644
--- a/pf4j/src/test/java/org/pf4j/DefaultPluginFactoryTest.java
+++ b/pf4j/src/test/java/org/pf4j/DefaultPluginFactoryTest.java
@@ -17,6 +17,7 @@ package org.pf4j;
 
 import org.junit.jupiter.api.Test;
 import org.pf4j.test.AnotherFailTestPlugin;
+import org.pf4j.test.AnotherTestPlugin;
 import org.pf4j.test.FailTestPlugin;
 import org.pf4j.test.TestPlugin;
 
@@ -49,6 +50,22 @@ public class DefaultPluginFactoryTest {
     }
 
     @Test
+    public void pluginConstructorNoParameters() {
+        PluginDescriptor pluginDescriptor = mock(PluginDescriptor.class);
+        when(pluginDescriptor.getPluginClass()).thenReturn(AnotherTestPlugin.class.getName());
+
+        PluginWrapper pluginWrapper = mock(PluginWrapper.class);
+        when(pluginWrapper.getDescriptor()).thenReturn(pluginDescriptor);
+        when(pluginWrapper.getPluginClassLoader()).thenReturn(getClass().getClassLoader());
+
+        PluginFactory pluginFactory = new DefaultPluginFactory();
+
+        Plugin result = pluginFactory.create(pluginWrapper);
+        assertNotNull(result);
+        assertThat(result, instanceOf(AnotherTestPlugin.class));
+    }
+
+    @Test
     public void testCreateFail() {
         PluginDescriptor pluginDescriptor = mock(PluginDescriptor.class);
         when(pluginDescriptor.getPluginClass()).thenReturn(FailTestPlugin.class.getName());
diff --git a/pf4j/src/test/java/org/pf4j/test/AnotherFailTestPlugin.java b/pf4j/src/test/java/org/pf4j/test/AnotherFailTestPlugin.java
index d97b32c..79aa41b 100644
--- a/pf4j/src/test/java/org/pf4j/test/AnotherFailTestPlugin.java
+++ b/pf4j/src/test/java/org/pf4j/test/AnotherFailTestPlugin.java
@@ -19,7 +19,7 @@ import org.pf4j.Plugin;
 
 /**
  * A wrong {@link org.pf4j.Plugin}.
- * It's wrong because it doesn't contain a constructor with one parameter ({@link org.pf4j.PluginWrapper} as parameter type).
+ * It's wrong because it calls super constructor with {@code null} for ({@link org.pf4j.PluginWrapper} parameter).
  *
  * @author Mario Franco
  */
diff --git a/pf4j/src/test/java/org/pf4j/test/AnotherTestPlugin.java b/pf4j/src/test/java/org/pf4j/test/AnotherTestPlugin.java
new file mode 100644
index 0000000..f2e10c1
--- /dev/null
+++ b/pf4j/src/test/java/org/pf4j/test/AnotherTestPlugin.java
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2012-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.pf4j.test;
+
+import org.pf4j.Plugin;
+
+/**
+ * A simple {@link Plugin}.
+ *
+ * In real applications you don't need to create a plugin like this if you are not interested in lifecycle events.
+ * {@code PF4J} will automatically create a plugin similar to this (empty / dummy) if no class plugin is specified.
+ *
+ * @author Decebal Suiu
+ */
+public class AnotherTestPlugin extends Plugin {
+
+    public AnotherTestPlugin() {
+        super();
+    }
+
+}