Tabs to spaces

demo/plugins/plugin1/src/main/java/org/pf4j/demo/welcome/WelcomePlugin.java

@@ -37,7 +37,7 @@ public class WelcomePlugin extends Plugin {
         System.out.println("WelcomePlugin.start()");
         // for testing the development mode
         if (RuntimeMode.DEVELOPMENT.equals(wrapper.getRuntimeMode())) {
-        	System.out.println(StringUtils.upperCase("WelcomePlugin"));
+            System.out.println(StringUtils.upperCase("WelcomePlugin"));
         }
     }
 
@@ -49,7 +49,7 @@ public class WelcomePlugin extends Plugin {
     @Extension
     public static class WelcomeGreeting implements Greeting {
 
-    	@Override
+        @Override
         public String getGreeting() {
             return "Welcome";
         }

demo/plugins/plugin2/src/main/java/org/pf4j/demo/hello/HelloPlugin.java

@@ -44,7 +44,7 @@ public class HelloPlugin extends Plugin {
     @Extension(ordinal=1)
     public static class HelloGreeting implements Greeting {
 
-    	@Override
+        @Override
         public String getGreeting() {
             return "Hello";
         }

demo_gradle/app/src/main/java/org/pf4j/demo/Boot.java

@@ -94,19 +94,19 @@ public class Boot {
         /*
         Runtime.getRuntime().addShutdownHook(new Thread() {
 
-			@Override
-			public void run() {
-				pluginManager.stopPlugins();
-			}
+            @Override
+            public void run() {
+                pluginManager.stopPlugins();
+            }
 
         });
         */
     }
 
-	private static void printLogo() {
-    	logger.info(StringUtils.repeat("#", 40));
-    	logger.info(StringUtils.center("PF4J-DEMO", 40));
-    	logger.info(StringUtils.repeat("#", 40));
-	}
+    private static void printLogo() {
+        logger.info(StringUtils.repeat("#", 40));
+        logger.info(StringUtils.center("PF4J-DEMO", 40));
+        logger.info(StringUtils.repeat("#", 40));
+    }
 
 }

demo_gradle/plugins/plugin1/src/main/java/org/pf4j/demo/welcome/WelcomePlugin.java

@@ -28,6 +28,7 @@ import org.pf4j.demo.api.Greeting;
  * @author Decebal Suiu
  */
 public class WelcomePlugin extends Plugin {
+
     private static final Logger logger = LoggerFactory.getLogger(WelcomePlugin.class);
 
     public WelcomePlugin(PluginWrapper wrapper) {
@@ -37,7 +38,7 @@ public class WelcomePlugin extends Plugin {
     @Override
     public void start() {
         logger.info("WelcomePlugin.start()");
-        	logger.info(StringUtils.upperCase("WelcomePlugin"));
+        logger.info(StringUtils.upperCase("WelcomePlugin"));
     }
 
     @Override
@@ -48,7 +49,7 @@ public class WelcomePlugin extends Plugin {
     @Extension
     public static class WelcomeGreeting implements Greeting {
 
-    	@Override
+        @Override
         public String getGreeting() {
             return "Welcome";
         }

demo_gradle/plugins/plugin2/src/main/java/org/pf4j/demo/hello/HelloPlugin.java

@@ -47,7 +47,7 @@ public class HelloPlugin extends Plugin {
     @Extension(ordinal=1)
     public static class HelloGreeting implements Greeting {
 
-    	@Override
+        @Override
         public String getGreeting() {
             return "Hello";
         }

pf4j/src/main/java/org/pf4j/DefaultExtensionFinder.java

@@ -31,7 +31,7 @@ public class DefaultExtensionFinder implements ExtensionFinder, PluginStateListe
     protected PluginManager pluginManager;
     protected List<ExtensionFinder> finders = new ArrayList<>();
 
-	public DefaultExtensionFinder(PluginManager pluginManager) {
+    public DefaultExtensionFinder(PluginManager pluginManager) {
         this.pluginManager = pluginManager;
 
         add(new LegacyExtensionFinder(pluginManager));

pf4j/src/main/java/org/pf4j/DefaultPluginManager.java

@@ -29,7 +29,7 @@ import java.nio.file.Path;
  */
 public class DefaultPluginManager extends AbstractPluginManager {
 
-	private static final Logger log = LoggerFactory.getLogger(DefaultPluginManager.class);
+    private static final Logger log = LoggerFactory.getLogger(DefaultPluginManager.class);
 
     protected PluginClasspath pluginClasspath;
 
@@ -60,7 +60,7 @@ public class DefaultPluginManager extends AbstractPluginManager {
 
     @Override
     protected ExtensionFinder createExtensionFinder() {
-    	DefaultExtensionFinder extensionFinder = new DefaultExtensionFinder(this);
+        DefaultExtensionFinder extensionFinder = new DefaultExtensionFinder(this);
         addPluginStateListener(extensionFinder);
 
         return extensionFinder;
@@ -120,7 +120,7 @@ public class DefaultPluginManager extends AbstractPluginManager {
         }
 
         log.info("PF4J version {} in '{}' mode", getVersion(), getRuntimeMode());
-	}
+    }
 
     /**
      * Load a plugin from disk. If the path is a zip file, first unpack

pf4j/src/main/java/org/pf4j/DependencyResolver.java

@@ -39,9 +39,9 @@ import java.util.Map;
  */
 public class DependencyResolver {
 
-	private static final Logger log = LoggerFactory.getLogger(DependencyResolver.class);
+    private static final Logger log = LoggerFactory.getLogger(DependencyResolver.class);
 
-	private VersionManager versionManager;
+    private VersionManager versionManager;
 
     private DirectedGraph<String> dependenciesGraph; // the value is 'pluginId'
     private DirectedGraph<String> dependentsGraph; // the value is 'pluginId'
@@ -168,10 +168,10 @@ public class DependencyResolver {
             "' for plugin '" + dependent.getPluginId() + "'");
     }
 
-	public static class Result {
+    public static class Result {
 
-	    private boolean cyclicDependency;
-	    private List<String> notFoundDependencies; // value is "pluginId"
+        private boolean cyclicDependency;
+        private List<String> notFoundDependencies; // value is "pluginId"
         private List<String> sortedPlugins; // value is "pluginId"
         private List<WrongDependencyVersion> wrongVersionDependencies;
 
@@ -194,9 +194,9 @@ public class DependencyResolver {
             return cyclicDependency;
         }
 
-	    /**
-	     * Returns a list with dependencies required that were not found.
-	     */
+        /**
+         * Returns a list with dependencies required that were not found.
+         */
         public List<String> getNotFoundDependencies() {
             return notFoundDependencies;
         }

pf4j/src/main/java/org/pf4j/Extension.java

@@ -32,6 +32,6 @@ import java.lang.annotation.Target;
 @Documented
 public @interface Extension {
 
-	int ordinal() default 0;
+    int ordinal() default 0;
 
 }

pf4j/src/main/java/org/pf4j/LegacyExtensionFinder.java

@@ -39,11 +39,11 @@ import java.util.Set;
  */
 public class LegacyExtensionFinder extends AbstractExtensionFinder {
 
-	private static final Logger log = LoggerFactory.getLogger(LegacyExtensionFinder.class);
+    private static final Logger log = LoggerFactory.getLogger(LegacyExtensionFinder.class);
 
-	public LegacyExtensionFinder(PluginManager pluginManager) {
+    public LegacyExtensionFinder(PluginManager pluginManager) {
         super(pluginManager);
-	}
+    }
 
     @Override
     public Map<String, Set<String>> readClasspathStorages() {

pf4j/src/main/java/org/pf4j/ManifestPluginDescriptorFinder.java

@@ -43,11 +43,11 @@ public class ManifestPluginDescriptorFinder implements PluginDescriptorFinder {
     }
 
     @Override
-	public PluginDescriptor find(Path pluginPath) throws PluginException {
+    public PluginDescriptor find(Path pluginPath) throws PluginException {
         Manifest manifest = readManifest(pluginPath);
 
         return createPluginDescriptor(manifest);
-	}
+    }
 
     protected Manifest readManifest(Path pluginPath) throws PluginException {
         if (FileUtils.isJarFile(pluginPath)) {

pf4j/src/main/java/org/pf4j/PluginClassLoader.java

@@ -37,11 +37,11 @@ public class PluginClassLoader extends URLClassLoader {
     private static final Logger log = LoggerFactory.getLogger(PluginClassLoader.class);
 
     private static final String JAVA_PACKAGE_PREFIX = "java.";
-	private static final String PLUGIN_PACKAGE_PREFIX = "org.pf4j.";
+    private static final String PLUGIN_PACKAGE_PREFIX = "org.pf4j.";
 
-	private PluginManager pluginManager;
-	private PluginDescriptor pluginDescriptor;
-	private boolean parentFirst;
+    private PluginManager pluginManager;
+    private PluginDescriptor pluginDescriptor;
+    private boolean parentFirst;
 
     public PluginClassLoader(PluginManager pluginManager, PluginDescriptor pluginDescriptor, ClassLoader parent) {
         this(pluginManager, pluginDescriptor, parent, false);
@@ -52,20 +52,20 @@ public class PluginClassLoader extends URLClassLoader {
      * before trying to load the a class through this loader.
      */
     public PluginClassLoader(PluginManager pluginManager, PluginDescriptor pluginDescriptor, ClassLoader parent, boolean parentFirst) {
-		super(new URL[0], parent);
+        super(new URL[0], parent);
 
-		this.pluginManager = pluginManager;
-		this.pluginDescriptor = pluginDescriptor;
-		this.parentFirst = parentFirst;
-	}
+        this.pluginManager = pluginManager;
+        this.pluginDescriptor = pluginDescriptor;
+        this.parentFirst = parentFirst;
+    }
 
     @Override
-	public void addURL(URL url) {
+    public void addURL(URL url) {
         log.debug("Add '{}'", url);
-		super.addURL(url);
-	}
+        super.addURL(url);
+    }
 
-	public void addFile(File file) {
+    public void addFile(File file) {
         try {
             addURL(file.getCanonicalFile().toURI().toURL());
         } catch (IOException e) {
@@ -80,7 +80,7 @@ public class PluginClassLoader extends URLClassLoader {
      * via the standard {@link ClassLoader#loadClass(String)} mechanism.
      * Use {@link #parentFirst} to change the loading strategy.
      */
-	@Override
+    @Override
     public Class<?> loadClass(String className) throws ClassNotFoundException {
         synchronized (getClassLoadingLock(className)) {
             // first check whether it's a system class, delegate to the system loader

pf4j/src/main/java/org/pf4j/PluginDescriptorFinder.java

@@ -35,6 +35,6 @@ public interface PluginDescriptorFinder {
      */
     boolean isApplicable(Path pluginPath);
 
-	PluginDescriptor find(Path pluginPath) throws PluginException;
+    PluginDescriptor find(Path pluginPath) throws PluginException;
 
 }

pf4j/src/main/java/org/pf4j/PluginManager.java

@@ -40,12 +40,12 @@ public interface PluginManager {
     /**
      * Retrieves all resolved plugins (with resolved dependency).
      */
-  	List<PluginWrapper> getResolvedPlugins();
+    List<PluginWrapper> getResolvedPlugins();
 
-	/**
-	 * Retrieves all unresolved plugins (with unresolved dependency).
-	 */
-  	List<PluginWrapper> getUnresolvedPlugins();
+    /**
+     * Retrieves all unresolved plugins (with unresolved dependency).
+     */
+    List<PluginWrapper> getUnresolvedPlugins();
 
     /**
      * Retrieves all started plugins.
@@ -71,7 +71,7 @@ public interface PluginManager {
      * @param pluginPath
      * @return the pluginId of the installed plugin or null
      */
-	String loadPlugin(Path pluginPath);
+    String loadPlugin(Path pluginPath);
 
     /**
      * Start all active plugins.
@@ -129,13 +129,13 @@ public interface PluginManager {
      */
     boolean deletePlugin(String pluginId);
 
-	ClassLoader getPluginClassLoader(String pluginId);
+    ClassLoader getPluginClassLoader(String pluginId);
 
     <T> List<Class<T>> getExtensionClasses(Class<T> type);
 
     <T> List<Class<T>> getExtensionClasses(Class<T> type, String pluginId);
 
-	<T> List<T> getExtensions(Class<T> type);
+    <T> List<T> getExtensions(Class<T> type);
 
     <T> List<T> getExtensions(Class<T> type, String pluginId);
 
@@ -146,9 +146,9 @@ public interface PluginManager {
     ExtensionFactory getExtensionFactory();
 
     /**
-	 * The runtime mode. Must currently be either DEVELOPMENT or DEPLOYMENT.
-	 */
-	RuntimeMode getRuntimeMode();
+     * The runtime mode. Must currently be either DEVELOPMENT or DEPLOYMENT.
+     */
+    RuntimeMode getRuntimeMode();
 
     /**
      * Retrieves the {@link PluginWrapper} that loaded the given class 'clazz'.

pf4j/src/main/java/org/pf4j/PluginState.java

@@ -23,7 +23,7 @@ public class PluginState {
     /**
      * The runtime knows the plugin is there. It knows about the plugin path, the plugin descriptor.
      */
-	public static final PluginState CREATED = new PluginState("CREATED");
+    public static final PluginState CREATED = new PluginState("CREATED");
 
     /**
      * The plugin cannot be used.
@@ -39,18 +39,18 @@ public class PluginState {
     /**
      * The {@link Plugin#start()} has executed. A started plugin may contribute extensions.
      */
-	public static final PluginState STARTED = new PluginState("STARTED");
+    public static final PluginState STARTED = new PluginState("STARTED");
 
     /**
      * The {@link Plugin#stop()} has executed.
      */
     public static final PluginState STOPPED = new PluginState("STOPPED");
 
-	private String status;
+    private String status;
 
-	private PluginState(String status) {
-		this.status = status;
-	}
+    private PluginState(String status) {
+        this.status = status;
+    }
 
     @Override
     public boolean equals(Object o) {
@@ -68,8 +68,8 @@ public class PluginState {
     }
 
     @Override
-	public String toString() {
-		return status;
-	}
+    public String toString() {
+        return status;
+    }
 
 }

pf4j/src/main/java/org/pf4j/PluginWrapper.java

@@ -25,23 +25,23 @@ import java.nio.file.Path;
 public class PluginWrapper {
 
     private PluginManager pluginManager;
-	private PluginDescriptor descriptor;
-	private Path pluginPath;
-	private ClassLoader pluginClassLoader;
-	private PluginFactory pluginFactory;
-	private PluginState pluginState;
-	private RuntimeMode runtimeMode;
+    private PluginDescriptor descriptor;
+    private Path pluginPath;
+    private ClassLoader pluginClassLoader;
+    private PluginFactory pluginFactory;
+    private PluginState pluginState;
+    private RuntimeMode runtimeMode;
 
     Plugin plugin; // cache
 
-	public PluginWrapper(PluginManager pluginManager, PluginDescriptor descriptor, Path pluginPath, ClassLoader pluginClassLoader) {
+    public PluginWrapper(PluginManager pluginManager, PluginDescriptor descriptor, Path pluginPath, ClassLoader pluginClassLoader) {
         this.pluginManager = pluginManager;
-		this.descriptor = descriptor;
-		this.pluginPath = pluginPath;
-		this.pluginClassLoader = pluginClassLoader;
+        this.descriptor = descriptor;
+        this.pluginPath = pluginPath;
+        this.pluginClassLoader = pluginClassLoader;
 
-		pluginState = PluginState.CREATED;
-	}
+        pluginState = PluginState.CREATED;
+    }
 
     /**
      * Returns the plugin manager.
@@ -54,23 +54,23 @@ public class PluginWrapper {
      * Returns the plugin descriptor.
      */
     public PluginDescriptor getDescriptor() {
-    	return descriptor;
+        return descriptor;
     }
 
     /**
      * Returns the path of this plugin.
      */
     public Path getPluginPath() {
-    	return pluginPath;
+        return pluginPath;
     }
 
     /**
      * Returns the plugin class loader used to load classes and resources
-	 * for this plug-in. The class loader can be used to directly access
-	 * plug-in resources and classes.
-	 */
+     * for this plug-in. The class loader can be used to directly access
+     * plug-in resources and classes.
+     */
     public ClassLoader getPluginClassLoader() {
-    	return pluginClassLoader;
+        return pluginClassLoader;
     }
 
     public Plugin getPlugin() {
@@ -79,15 +79,15 @@ public class PluginWrapper {
         }
 
         return plugin;
-	}
+    }
 
-	public PluginState getPluginState() {
-		return pluginState;
-	}
+    public PluginState getPluginState() {
+        return pluginState;
+    }
 
-	public RuntimeMode getRuntimeMode() {
-		return runtimeMode;
-	}
+    public RuntimeMode getRuntimeMode() {
+        return runtimeMode;
+    }
 
     /**
      * Shortcut
@@ -96,49 +96,49 @@ public class PluginWrapper {
         return getDescriptor().getPluginId();
     }
 
-	@Override
-	public int hashCode() {
-		final int prime = 31;
-		int result = 1;
-		result = prime * result + descriptor.getPluginId().hashCode();
-
-		return result;
-	}
-
-	@Override
-	public boolean equals(Object obj) {
-		if (this == obj) {
-			return true;
-		}
-
-		if (obj == null) {
-			return false;
-		}
-
-		if (getClass() != obj.getClass()) {
-			return false;
-		}
-
-		PluginWrapper other = (PluginWrapper) obj;
-		if (!descriptor.getPluginId().equals(other.descriptor.getPluginId())) {
-			return false;
-		}
-
-		return true;
-	}
-
-	@Override
-	public String toString() {
-		return "PluginWrapper [descriptor=" + descriptor + ", pluginPath=" + pluginPath + "]";
-	}
-
-	void setPluginState(PluginState pluginState) {
-		this.pluginState = pluginState;
-	}
-
-	void setRuntimeMode(RuntimeMode runtimeMode) {
-		this.runtimeMode = runtimeMode;
-	}
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + descriptor.getPluginId().hashCode();
+
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj == null) {
+            return false;
+        }
+
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+
+        PluginWrapper other = (PluginWrapper) obj;
+        if (!descriptor.getPluginId().equals(other.descriptor.getPluginId())) {
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public String toString() {
+        return "PluginWrapper [descriptor=" + descriptor + ", pluginPath=" + pluginPath + "]";
+    }
+
+    void setPluginState(PluginState pluginState) {
+        this.pluginState = pluginState;
+    }
+
+    void setRuntimeMode(RuntimeMode runtimeMode) {
+        this.runtimeMode = runtimeMode;
+    }
 
     void setPluginFactory(PluginFactory pluginFactory) {
         this.pluginFactory = pluginFactory;

pf4j/src/main/java/org/pf4j/PropertiesPluginDescriptorFinder.java

@@ -34,19 +34,19 @@ import java.util.Properties;
  */
 public class PropertiesPluginDescriptorFinder implements PluginDescriptorFinder {
 
-	private static final Logger log = LoggerFactory.getLogger(PropertiesPluginDescriptorFinder.class);
+    private static final Logger log = LoggerFactory.getLogger(PropertiesPluginDescriptorFinder.class);
 
-	private static final String DEFAULT_PROPERTIES_FILE_NAME = "plugin.properties";
+    private static final String DEFAULT_PROPERTIES_FILE_NAME = "plugin.properties";
 
-	protected String propertiesFileName;
+    protected String propertiesFileName;
 
-	public PropertiesPluginDescriptorFinder() {
-		this(DEFAULT_PROPERTIES_FILE_NAME);
-	}
+    public PropertiesPluginDescriptorFinder() {
+        this(DEFAULT_PROPERTIES_FILE_NAME);
+    }
 
-	public PropertiesPluginDescriptorFinder(String propertiesFileName) {
+    public PropertiesPluginDescriptorFinder(String propertiesFileName) {
         this.propertiesFileName = propertiesFileName;
-	}
+    }
 
     @Override
     public boolean isApplicable(Path pluginPath) {
@@ -54,11 +54,11 @@ public class PropertiesPluginDescriptorFinder implements PluginDescriptorFinder
     }
 
     @Override
-	public PluginDescriptor find(Path pluginPath) throws PluginException {
+    public PluginDescriptor find(Path pluginPath) throws PluginException {
         Properties properties = readProperties(pluginPath);
 
         return createPluginDescriptor(properties);
-	}
+    }
 
     protected Properties readProperties(Path pluginPath) throws PluginException {
         Path propertiesPath = getPropertiesPath(pluginPath, propertiesFileName);
@@ -82,10 +82,10 @@ public class PropertiesPluginDescriptorFinder implements PluginDescriptorFinder
     }
 
     protected Path getPropertiesPath(Path pluginPath, String propertiesFileName) throws PluginException {
-	    if (Files.isDirectory(pluginPath)) {
+        if (Files.isDirectory(pluginPath)) {
             return pluginPath.resolve(Paths.get(propertiesFileName));
         } else {
-	        // it's a jar file
+            // it's a jar file
             try {
                 return FileUtils.getPath(pluginPath, propertiesFileName);
             } catch (IOException e) {

pf4j/src/main/java/org/pf4j/processor/ExtensionAnnotationProcessor.java

@@ -58,17 +58,17 @@ public class ExtensionAnnotationProcessor extends AbstractProcessor {
     }
 
     @Override
-	public SourceVersion getSupportedSourceVersion() {
-		return SourceVersion.latest();
-	}
+    public SourceVersion getSupportedSourceVersion() {
+        return SourceVersion.latest();
+    }
 
-	@Override
-	public Set<String> getSupportedAnnotationTypes() {
-		Set<String> annotationTypes = new HashSet<>();
+    @Override
+    public Set<String> getSupportedAnnotationTypes() {
+        Set<String> annotationTypes = new HashSet<>();
         annotationTypes.add(Extension.class.getName());
 
         return annotationTypes;
-	}
+    }
 
     @Override
     public Set<String> getSupportedOptions() {
@@ -79,17 +79,17 @@ public class ExtensionAnnotationProcessor extends AbstractProcessor {
     }
 
     @Override
-	public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
-		if (roundEnv.processingOver()) {
+    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
+        if (roundEnv.processingOver()) {
             return false;
         }
 
         info("Processing @%s", Extension.class);
-		for (Element element : roundEnv.getElementsAnnotatedWith(Extension.class)) {
+        for (Element element : roundEnv.getElementsAnnotatedWith(Extension.class)) {
             // check if @Extension is put on class and not on method or constructor
             if (!(element instanceof TypeElement)) {
-				continue;
-			}
+                continue;
+            }
 
             // check if class extends/implements an extension point
             if (!isExtension(element.asType())) {
@@ -130,8 +130,8 @@ public class ExtensionAnnotationProcessor extends AbstractProcessor {
         // write extensions
         storage.write(extensions);
 
-		return false;
-	}
+        return false;
+    }
 
     public ProcessingEnvironment getProcessingEnvironment() {
         return processingEnv;

pf4j/src/main/java/org/pf4j/util/DirectedGraph.java

@@ -41,7 +41,7 @@ public class DirectedGraph<V> {
      */
     public void addVertex(V vertex) {
         if (containsVertex(vertex)) {
-        	return;
+            return;
         }
 
         neighbors.put(vertex, new ArrayList<V>());
@@ -94,7 +94,7 @@ public class DirectedGraph<V> {
     public Map<V, Integer> outDegree() {
         Map<V, Integer> result = new HashMap<>();
         for (V vertex : neighbors.keySet()) {
-        	result.put(vertex, neighbors.get(vertex).size());
+            result.put(vertex, neighbors.get(vertex).size());
         }
 
         return result;
@@ -106,7 +106,7 @@ public class DirectedGraph<V> {
     public Map<V, Integer> inDegree() {
         Map<V, Integer> result = new HashMap<>();
         for (V vertex : neighbors.keySet()) {
-        	result.put(vertex, 0); // all in-degrees are 0
+            result.put(vertex, 0); // all in-degrees are 0
         }
         for (V from : neighbors.keySet()) {
             for (V to : neighbors.get(from)) {
@@ -128,7 +128,7 @@ public class DirectedGraph<V> {
         Stack<V> zeroVertices = new Stack<>(); // stack as good as any here
         for (V v : degree.keySet()) {
             if (degree.get(v) == 0) {
-            	zeroVertices.push(v);
+                zeroVertices.push(v);
             }
         }
 
@@ -142,14 +142,14 @@ public class DirectedGraph<V> {
                 degree.put(neighbor, degree.get(neighbor) - 1);
                 // remember any vertices that now have zero in-degree
                 if (degree.get(neighbor) == 0) {
-                	zeroVertices.push(neighbor);
+                    zeroVertices.push(neighbor);
                 }
             }
         }
 
         // check that we have used the entire graph (if not, there was a cycle)
         if (result.size() != neighbors.size()) {
-        	return null;
+            return null;
         }
 
         return result;
@@ -159,14 +159,14 @@ public class DirectedGraph<V> {
      * Report (as a List) the reverse topological sort of the vertices; null for no such sort.
      */
     public List<V> reverseTopologicalSort() {
-    	List<V> list = topologicalSort();
-    	if (list == null) {
-    		return null;
-    	}
+        List<V> list = topologicalSort();
+        if (list == null) {
+            return null;
+        }
 
-    	Collections.reverse(list);
+        Collections.reverse(list);
 
-    	return list;
+        return list;
     }
 
     /**
@@ -183,7 +183,7 @@ public class DirectedGraph<V> {
     public String toString() {
         StringBuffer sb = new StringBuffer();
         for (V vertex : neighbors.keySet()) {
-        	sb.append("\n   " + vertex + " -> " + neighbors.get(vertex));
+            sb.append("\n   " + vertex + " -> " + neighbors.get(vertex));
         }
 
         return sb.toString();

pf4j/src/main/java/org/pf4j/util/DirectoryFileFilter.java

@@ -25,7 +25,7 @@ import java.io.FileFilter;
  */
 public class DirectoryFileFilter implements FileFilter {
 
-	@Override
+    @Override
     public boolean accept(File file) {
         return file.isDirectory();
     }

pf4j/src/main/java/org/pf4j/util/FileUtils.java

@@ -47,34 +47,34 @@ public class FileUtils {
 
     public static List<String> readLines(Path path, boolean ignoreComments) throws IOException {
         File file = path.toFile();
-		if (!file.exists() || !file.isFile()) {
-			return new ArrayList<>();
-		}
+        if (!file.exists() || !file.isFile()) {
+            return new ArrayList<>();
+        }
 
-		List<String> lines = new ArrayList<>();
+        List<String> lines = new ArrayList<>();
 
-		try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
-			String line;
-			while ((line = reader.readLine()) != null) {
-				if (ignoreComments && !line.startsWith("#") && !lines.contains(line)) {
-					lines.add(line);
-				}
-			}
-		}
+        try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                if (ignoreComments && !line.startsWith("#") && !lines.contains(line)) {
+                    lines.add(line);
+                }
+            }
+        }
 
-		return lines;
-	}
+        return lines;
+    }
 
     public static void writeLines(Collection<String> lines, File file) throws IOException {
         Files.write(file.toPath(), lines, StandardCharsets.UTF_8);
     }
 
     /**
-   	 * Delete a file or recursively delete a folder, do not follow symlinks.
-   	 *
-   	 * @param path the file or folder to delete
-   	 * @throws IOException if something goes wrong
-   	 */
+     * Delete a file or recursively delete a folder, do not follow symlinks.
+     *
+     * @param path the file or folder to delete
+     * @throws IOException if something goes wrong
+     */
     public static void delete(Path path) throws IOException {
         Files.walkFileTree(path, new SimpleFileVisitor<Path>() {
 
@@ -95,13 +95,13 @@ public class FileUtils {
            }
 
         });
-	}
+    }
 
-	public static List<File> getJars(Path folder) {
-	    List<File> bucket = new ArrayList<>();
-	    getJars(bucket, folder);
+    public static List<File> getJars(Path folder) {
+        List<File> bucket = new ArrayList<>();
+        getJars(bucket, folder);
 
-	    return bucket;
+        return bucket;
     }
 
     private static void getJars(final List<File> bucket, Path folder) {

pf4j/src/main/java/org/pf4j/util/HiddenFilter.java

@@ -25,9 +25,9 @@ import java.io.FileFilter;
  */
 public class HiddenFilter implements FileFilter {
 
-	@Override
-	public boolean accept(File file) {
-		return file.isHidden();
-	}
+    @Override
+    public boolean accept(File file) {
+        return file.isHidden();
+    }
 
 }

pf4j/src/main/java/org/pf4j/util/StringUtils.java

@@ -20,9 +20,9 @@ package org.pf4j.util;
  */
 public class StringUtils {
 
-	public static boolean isNullOrEmpty(String str) {
-		return (str == null) || str.isEmpty();
-	}
+    public static boolean isNullOrEmpty(String str) {
+        return (str == null) || str.isEmpty();
+    }
 
     public static boolean isNotNullOrEmpty(String str) {
         return !isNullOrEmpty(str);

pf4j/src/main/java/org/pf4j/util/Unzip.java

@@ -34,7 +34,7 @@ import org.slf4j.LoggerFactory;
  */
 public class Unzip {
 
-	private static final Logger log = LoggerFactory.getLogger(Unzip.class);
+    private static final Logger log = LoggerFactory.getLogger(Unzip.class);
 
     /**
      * Holds the destination directory.
@@ -71,7 +71,7 @@ public class Unzip {
             FileUtils.delete(destination.toPath());
         }
 
-    	try (ZipInputStream zipInputStream = new ZipInputStream(new FileInputStream(source))) {
+        try (ZipInputStream zipInputStream = new ZipInputStream(new FileInputStream(source))) {
             ZipEntry zipEntry;
             while ((zipEntry = zipInputStream.getNextEntry()) != null) {
                 try {