diff --git a/reactor/src/main/java/com/iluwatar/reactor/app/App.java b/reactor/src/main/java/com/iluwatar/reactor/app/App.java
index 8ccbe3145..0804f8862 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/app/App.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/app/App.java
@@ -23,10 +23,6 @@
 
 package com.iluwatar.reactor.app;
 
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.List;
-
 import com.iluwatar.reactor.framework.AbstractNioChannel;
 import com.iluwatar.reactor.framework.ChannelHandler;
 import com.iluwatar.reactor.framework.Dispatcher;
@@ -34,19 +30,20 @@ import com.iluwatar.reactor.framework.NioDatagramChannel;
 import com.iluwatar.reactor.framework.NioReactor;
 import com.iluwatar.reactor.framework.NioServerSocketChannel;
 import com.iluwatar.reactor.framework.ThreadPoolDispatcher;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
 
 /**
  * This application demonstrates Reactor pattern. The example demonstrated is a Distributed Logging
  * Service where it listens on multiple TCP or UDP sockets for incoming log requests.
- * 
- * <p>
- * <i>INTENT</i> <br>
+ *
+ * <p><i>INTENT</i> <br>
  * The Reactor design pattern handles service requests that are delivered concurrently to an
  * application by one or more clients. The application can register specific handlers for processing
  * which are called by reactor on specific events.
- * 
- * <p>
- * <i>PROBLEM</i> <br>
+ *
+ * <p><i>PROBLEM</i> <br>
  * Server applications in a distributed system must handle multiple clients that send them service
  * requests. Following forces need to be resolved:
  * <ul>
@@ -55,9 +52,8 @@ import com.iluwatar.reactor.framework.ThreadPoolDispatcher;
  * <li>Programming Simplicity</li>
  * <li>Adaptability</li>
  * </ul>
- * 
- * <p>
- * <i>PARTICIPANTS</i> <br>
+ *
+ * <p><i>PARTICIPANTS</i> <br>
  * <ul>
  * <li>Synchronous Event De-multiplexer
  * <p>
@@ -89,7 +85,6 @@ import com.iluwatar.reactor.framework.ThreadPoolDispatcher;
  * separate thread for each client, which provides better scalability under load (number of clients
  * increase).
  * The example uses Java NIO framework to implement the Reactor.
- * 
  */
 public class App {
 
@@ -100,7 +95,7 @@ public class App {
   /**
    * Creates an instance of App which will use provided dispatcher for dispatching events on
    * reactor.
-   * 
+   *
    * @param dispatcher the dispatcher that will be used to dispatch events.
    */
   public App(Dispatcher dispatcher) {
@@ -142,9 +137,9 @@ public class App {
 
   /**
    * Stops the NIO reactor. This is a blocking call.
-   * 
+   *
    * @throws InterruptedException if interrupted while stopping the reactor.
-   * @throws IOException if any I/O error occurs
+   * @throws IOException          if any I/O error occurs
    */
   public void stop() throws InterruptedException, IOException {
     reactor.stop();
diff --git a/reactor/src/main/java/com/iluwatar/reactor/app/AppClient.java b/reactor/src/main/java/com/iluwatar/reactor/app/AppClient.java
index 75db3079b..a15437396 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/app/AppClient.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/app/AppClient.java
@@ -23,9 +23,6 @@
 
 package com.iluwatar.reactor.app;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -39,6 +36,8 @@ import java.net.UnknownHostException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Represents the clients of Reactor pattern. Multiple clients are run concurrently and send logging
@@ -158,7 +157,7 @@ public class AppClient {
      * Creates a new UDP logging client.
      *
      * @param clientName the name of the client to be sent in logging requests.
-     * @param port the port on which client will send logging requests.
+     * @param port       the port on which client will send logging requests.
      * @throws UnknownHostException if localhost is unknown
      */
     public UdpLoggingClient(String clientName, int port) throws UnknownHostException {
diff --git a/reactor/src/main/java/com/iluwatar/reactor/app/LoggingHandler.java b/reactor/src/main/java/com/iluwatar/reactor/app/LoggingHandler.java
index f0de033be..edf7e26fd 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/app/LoggingHandler.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/app/LoggingHandler.java
@@ -23,12 +23,11 @@
 
 package com.iluwatar.reactor.app;
 
-import java.nio.ByteBuffer;
-import java.nio.channels.SelectionKey;
-
 import com.iluwatar.reactor.framework.AbstractNioChannel;
 import com.iluwatar.reactor.framework.ChannelHandler;
 import com.iluwatar.reactor.framework.NioDatagramChannel.DatagramPacket;
+import java.nio.ByteBuffer;
+import java.nio.channels.SelectionKey;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -63,7 +62,11 @@ public class LoggingHandler implements ChannelHandler {
     }
   }
 
-  private static void sendReply(AbstractNioChannel channel, DatagramPacket incomingPacket, SelectionKey key) {
+  private static void sendReply(
+      AbstractNioChannel channel,
+      DatagramPacket incomingPacket,
+      SelectionKey key
+  ) {
     /*
      * Create a reply acknowledgement datagram packet setting the receiver to the sender of incoming
      * message.
diff --git a/reactor/src/main/java/com/iluwatar/reactor/framework/AbstractNioChannel.java b/reactor/src/main/java/com/iluwatar/reactor/framework/AbstractNioChannel.java
index dd0572aef..6b356d021 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/framework/AbstractNioChannel.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/framework/AbstractNioChannel.java
@@ -35,13 +35,12 @@ import java.util.concurrent.ConcurrentLinkedQueue;
 /**
  * This represents the <i>Handle</i> of Reactor pattern. These are resources managed by OS which can
  * be submitted to {@link NioReactor}.
- * 
- * <p>
- * This class serves has the responsibility of reading the data when a read event occurs and writing
- * the data back when the channel is writable. It leaves the reading and writing of data on the
- * concrete implementation. It provides a block writing mechanism wherein when any
- * {@link ChannelHandler} wants to write data back, it queues the data in pending write queue and
- * clears it in block manner. This provides better throughput.
+ *
+ * <p>This class serves has the responsibility of reading the data when a read event occurs and
+ * writing the data back when the channel is writable. It leaves the reading and writing of data on
+ * the concrete implementation. It provides a block writing mechanism wherein when any {@link
+ * ChannelHandler} wants to write data back, it queues the data in pending write queue and clears it
+ * in block manner. This provides better throughput.
  */
 public abstract class AbstractNioChannel {
 
@@ -53,7 +52,7 @@ public abstract class AbstractNioChannel {
 
   /**
    * Creates a new channel.
-   * 
+   *
    * @param handler which will handle events occurring on this channel.
    * @param channel a NIO channel to be wrapped.
    */
@@ -70,6 +69,8 @@ public abstract class AbstractNioChannel {
   }
 
   /**
+   * Get channel.
+   *
    * @return the wrapped NIO channel.
    */
   public SelectableChannel getJavaChannel() {
@@ -77,9 +78,9 @@ public abstract class AbstractNioChannel {
   }
 
   /**
-   * The operation in which the channel is interested, this operation is provided to
-   * {@link Selector}.
-   * 
+   * The operation in which the channel is interested, this operation is provided to {@link
+   * Selector}.
+   *
    * @return interested operation.
    * @see SelectionKey
    */
@@ -87,7 +88,7 @@ public abstract class AbstractNioChannel {
 
   /**
    * Binds the channel on provided port.
-   * 
+   *
    * @throws IOException if any I/O error occurs.
    */
   public abstract void bind() throws IOException;
@@ -95,7 +96,7 @@ public abstract class AbstractNioChannel {
   /**
    * Reads the data using the key and returns the read data. The underlying channel should be
    * fetched using {@link SelectionKey#channel()}.
-   * 
+   *
    * @param key the key on which read event occurred.
    * @return data read.
    * @throws IOException if any I/O error occurs.
@@ -103,6 +104,8 @@ public abstract class AbstractNioChannel {
   public abstract Object read(SelectionKey key) throws IOException;
 
   /**
+   * Get handler.
+   *
    * @return the handler associated with this channel.
    */
   public ChannelHandler getHandler() {
@@ -130,9 +133,9 @@ public abstract class AbstractNioChannel {
 
   /**
    * Writes the data to the channel.
-   * 
+   *
    * @param pendingWrite the data to be written on channel.
-   * @param key the key which is writable.
+   * @param key          the key which is writable.
    * @throws IOException if any I/O error occurs.
    */
   protected abstract void doWrite(Object pendingWrite, SelectionKey key) throws IOException;
@@ -140,24 +143,23 @@ public abstract class AbstractNioChannel {
   /**
    * Queues the data for writing. The data is not guaranteed to be written on underlying channel
    * when this method returns. It will be written when the channel is flushed.
-   * 
-   * <p>
-   * This method is used by the {@link ChannelHandler} to send reply back to the client. <br>
+   *
+   * <p>This method is used by the {@link ChannelHandler} to send reply back to the client. <br>
    * Example:
-   * 
+   *
    * <pre>
    * <code>
    * {@literal @}Override
-   * public void handleChannelRead(AbstractNioChannel channel, Object readObject, SelectionKey key) {
-   *   byte[] data = ((ByteBuffer)readObject).array();
+   * public void handleChannelRead(AbstractNioChannel channel, Object readObj, SelectionKey key) {
+   *   byte[] data = ((ByteBuffer)readObj).array();
    *   ByteBuffer buffer = ByteBuffer.wrap("Server reply".getBytes());
    *   channel.write(buffer, key);
    * }
    * </code>
    * </pre>
-   * 
+   *
    * @param data the data to be written on underlying channel.
-   * @param key the key which is writable.
+   * @param key  the key which is writable.
    */
   public void write(Object data, SelectionKey key) {
     Queue<Object> pendingWrites = this.channelToPendingWrites.get(key.channel());
diff --git a/reactor/src/main/java/com/iluwatar/reactor/framework/ChannelHandler.java b/reactor/src/main/java/com/iluwatar/reactor/framework/ChannelHandler.java
index e7204a550..5bd145a38 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/framework/ChannelHandler.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/framework/ChannelHandler.java
@@ -28,19 +28,19 @@ import java.nio.channels.SelectionKey;
 /**
  * Represents the <i>EventHandler</i> of Reactor pattern. It handles the incoming events dispatched
  * to it by the {@link Dispatcher}. This is where the application logic resides.
- * 
- * <p>
- * A {@link ChannelHandler} can be associated with one or many {@link AbstractNioChannel}s, and
- * whenever an event occurs on any of the associated channels, the handler is notified of the event.
+ *
+ * <p>A {@link ChannelHandler} can be associated with one or many {@link AbstractNioChannel}s, and
+ * whenever an event occurs on any of the associated channels, the handler is notified of the
+ * event.
  */
 public interface ChannelHandler {
 
   /**
    * Called when the {@code channel} receives some data from remote peer.
-   * 
-   * @param channel the channel from which the data was received.
+   *
+   * @param channel    the channel from which the data was received.
    * @param readObject the data read.
-   * @param key the key on which read event occurred.
+   * @param key        the key on which read event occurred.
    */
   void handleChannelRead(AbstractNioChannel channel, Object readObject, SelectionKey key);
 }
diff --git a/reactor/src/main/java/com/iluwatar/reactor/framework/Dispatcher.java b/reactor/src/main/java/com/iluwatar/reactor/framework/Dispatcher.java
index 17ccb2ef8..0a2db2ca8 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/framework/Dispatcher.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/framework/Dispatcher.java
@@ -29,14 +29,12 @@ import java.nio.channels.SelectionKey;
  * Represents the event dispatching strategy. When {@link NioReactor} senses any event on the
  * registered {@link AbstractNioChannel}s then it de-multiplexes the event type, read or write or
  * connect, and then calls the {@link Dispatcher} to dispatch the read events. This decouples the
- * I/O processing from application specific processing. <br>
- * Dispatcher should call the {@link ChannelHandler} associated with the channel on which event
- * occurred.
- * 
- * <p>
- * The application can customize the way in which event is dispatched such as using the reactor
+ * I/O processing from application specific processing. <br> Dispatcher should call the {@link
+ * ChannelHandler} associated with the channel on which event occurred.
+ *
+ * <p>The application can customize the way in which event is dispatched such as using the reactor
  * thread to dispatch event to channels or use a worker pool to do the non I/O processing.
- * 
+ *
  * @see SameThreadDispatcher
  * @see ThreadPoolDispatcher
  */
@@ -45,19 +43,18 @@ public interface Dispatcher {
    * This hook method is called when read event occurs on particular channel. The data read is
    * provided in <code>readObject</code>. The implementation should dispatch this read event to the
    * associated {@link ChannelHandler} of <code>channel</code>.
-   * 
-   * <p>
-   * The type of <code>readObject</code> depends on the channel on which data was received.
-   * 
-   * @param channel on which read event occurred
+   *
+   * <p>The type of <code>readObject</code> depends on the channel on which data was received.
+   *
+   * @param channel    on which read event occurred
    * @param readObject object read by channel
-   * @param key on which event occurred
+   * @param key        on which event occurred
    */
   void onChannelReadEvent(AbstractNioChannel channel, Object readObject, SelectionKey key);
 
   /**
    * Stops dispatching events and cleans up any acquired resources such as threads.
-   * 
+   *
    * @throws InterruptedException if interrupted while stopping dispatcher.
    */
   void stop() throws InterruptedException;
diff --git a/reactor/src/main/java/com/iluwatar/reactor/framework/NioDatagramChannel.java b/reactor/src/main/java/com/iluwatar/reactor/framework/NioDatagramChannel.java
index f62e46e72..ba4b68231 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/framework/NioDatagramChannel.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/framework/NioDatagramChannel.java
@@ -23,9 +23,6 @@
 
 package com.iluwatar.reactor.framework;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.io.IOException;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
@@ -33,6 +30,8 @@ import java.net.SocketAddress;
 import java.nio.ByteBuffer;
 import java.nio.channels.DatagramChannel;
 import java.nio.channels.SelectionKey;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * A wrapper over {@link DatagramChannel} which can read and write data on a DatagramChannel.
@@ -46,11 +45,11 @@ public class NioDatagramChannel extends AbstractNioChannel {
   /**
    * Creates a {@link DatagramChannel} which will bind at provided port and use <code>handler</code>
    * to handle incoming events on this channel.
-   * <p>
-   * Note the constructor does not bind the socket, {@link #bind()} method should be called for
+   *
+   * <p>Note the constructor does not bind the socket, {@link #bind()} method should be called for
    * binding the socket.
-   * 
-   * @param port the port to be bound to listen for incoming datagram requests.
+   *
+   * @param port    the port to be bound to listen for incoming datagram requests.
    * @param handler the handler to be used for handling incoming requests on this channel.
    * @throws IOException if any I/O error occurs.
    */
@@ -69,7 +68,7 @@ public class NioDatagramChannel extends AbstractNioChannel {
 
   /**
    * Reads and returns a {@link DatagramPacket} from the underlying channel.
-   * 
+   *
    * @return the datagram packet read having the sender address.
    */
   @Override
@@ -89,6 +88,8 @@ public class NioDatagramChannel extends AbstractNioChannel {
   }
 
   /**
+   * Get datagram channel.
+   *
    * @return the underlying datagram channel.
    */
   @Override
@@ -98,7 +99,7 @@ public class NioDatagramChannel extends AbstractNioChannel {
 
   /**
    * Binds UDP socket on the provided <code>port</code>.
-   * 
+   *
    * @throws IOException if any I/O error occurs.
    */
   @Override
@@ -120,8 +121,8 @@ public class NioDatagramChannel extends AbstractNioChannel {
 
   /**
    * Writes the outgoing {@link DatagramPacket} to the channel. The intended receiver of the
-   * datagram packet must be set in the <code>data</code> using
-   * {@link DatagramPacket#setReceiver(SocketAddress)}.
+   * datagram packet must be set in the <code>data</code> using {@link
+   * DatagramPacket#setReceiver(SocketAddress)}.
    */
   @Override
   public void write(Object data, SelectionKey key) {
@@ -138,7 +139,7 @@ public class NioDatagramChannel extends AbstractNioChannel {
 
     /**
      * Creates a container with underlying data.
-     * 
+     *
      * @param data the underlying message to be written on channel.
      */
     public DatagramPacket(ByteBuffer data) {
@@ -146,6 +147,8 @@ public class NioDatagramChannel extends AbstractNioChannel {
     }
 
     /**
+     * Get sender address.
+     *
      * @return the sender address.
      */
     public SocketAddress getSender() {
@@ -154,7 +157,7 @@ public class NioDatagramChannel extends AbstractNioChannel {
 
     /**
      * Sets the sender address of this packet.
-     * 
+     *
      * @param sender the sender address.
      */
     public void setSender(SocketAddress sender) {
@@ -162,6 +165,8 @@ public class NioDatagramChannel extends AbstractNioChannel {
     }
 
     /**
+     * Get receiver address.
+     *
      * @return the receiver address.
      */
     public SocketAddress getReceiver() {
@@ -170,7 +175,7 @@ public class NioDatagramChannel extends AbstractNioChannel {
 
     /**
      * Sets the intended receiver address. This must be set when writing to the channel.
-     * 
+     *
      * @param receiver the receiver address.
      */
     public void setReceiver(SocketAddress receiver) {
@@ -178,6 +183,8 @@ public class NioDatagramChannel extends AbstractNioChannel {
     }
 
     /**
+     * Get data.
+     *
      * @return the underlying message that will be written on channel.
      */
     public ByteBuffer getData() {
diff --git a/reactor/src/main/java/com/iluwatar/reactor/framework/NioReactor.java b/reactor/src/main/java/com/iluwatar/reactor/framework/NioReactor.java
index 9c71ed80e..becf1fd2d 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/framework/NioReactor.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/framework/NioReactor.java
@@ -23,9 +23,6 @@
 
 package com.iluwatar.reactor.framework;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.io.IOException;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.Selector;
@@ -38,22 +35,23 @@ import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
- * This class acts as Synchronous Event De-multiplexer and Initiation Dispatcher of Reactor pattern. Multiple handles
- * i.e. {@link AbstractNioChannel}s can be registered to the reactor and it blocks for events from all these handles.
- * Whenever an event occurs on any of the registered handles, it synchronously de-multiplexes the event which can be any
- * of read, write or accept, and dispatches the event to the appropriate {@link ChannelHandler} using the
- * {@link Dispatcher}.
- * 
- * <p>
- * Implementation: A NIO reactor runs in its own thread when it is started using {@link #start()} method.
- * {@link NioReactor} uses {@link Selector} for realizing Synchronous Event De-multiplexing.
- * 
- * <p>
- * NOTE: This is one of the ways to implement NIO reactor and it does not take care of all possible edge cases which are
- * required in a real application. This implementation is meant to demonstrate the fundamental concepts that lie behind
- * Reactor pattern.
+ * This class acts as Synchronous Event De-multiplexer and Initiation Dispatcher of Reactor pattern.
+ * Multiple handles i.e. {@link AbstractNioChannel}s can be registered to the reactor and it blocks
+ * for events from all these handles. Whenever an event occurs on any of the registered handles, it
+ * synchronously de-multiplexes the event which can be any of read, write or accept, and dispatches
+ * the event to the appropriate {@link ChannelHandler} using the {@link Dispatcher}.
+ *
+ * <p>Implementation: A NIO reactor runs in its own thread when it is started using {@link
+ * #start()} method. {@link NioReactor} uses {@link Selector} for realizing Synchronous Event
+ * De-multiplexing.
+ *
+ * <p>NOTE: This is one of the ways to implement NIO reactor and it does not take care of all
+ * possible edge cases which are required in a real application. This implementation is meant to
+ * demonstrate the fundamental concepts that lie behind Reactor pattern.
  */
 public class NioReactor {
 
@@ -62,21 +60,20 @@ public class NioReactor {
   private final Selector selector;
   private final Dispatcher dispatcher;
   /**
-   * All the work of altering the SelectionKey operations and Selector operations are performed in the context of main
-   * event loop of reactor. So when any channel needs to change its readability or writability, a new command is added
-   * in the command queue and then the event loop picks up the command and executes it in next iteration.
+   * All the work of altering the SelectionKey operations and Selector operations are performed in
+   * the context of main event loop of reactor. So when any channel needs to change its readability
+   * or writability, a new command is added in the command queue and then the event loop picks up
+   * the command and executes it in next iteration.
    */
   private final Queue<Runnable> pendingCommands = new ConcurrentLinkedQueue<>();
   private final ExecutorService reactorMain = Executors.newSingleThreadExecutor();
 
   /**
-   * Creates a reactor which will use provided {@code dispatcher} to dispatch events. The application can provide
-   * various implementations of dispatcher which suits its needs.
-   * 
-   * @param dispatcher
-   *          a non-null dispatcher used to dispatch events on registered channels.
-   * @throws IOException
-   *           if any I/O error occurs.
+   * Creates a reactor which will use provided {@code dispatcher} to dispatch events. The
+   * application can provide various implementations of dispatcher which suits its needs.
+   *
+   * @param dispatcher a non-null dispatcher used to dispatch events on registered channels.
+   * @throws IOException if any I/O error occurs.
    */
   public NioReactor(Dispatcher dispatcher) throws IOException {
     this.dispatcher = dispatcher;
@@ -99,11 +96,9 @@ public class NioReactor {
 
   /**
    * Stops the reactor and related resources such as dispatcher.
-   * 
-   * @throws InterruptedException
-   *           if interrupted while stopping the reactor.
-   * @throws IOException
-   *           if any I/O error occurs.
+   *
+   * @throws InterruptedException if interrupted while stopping the reactor.
+   * @throws IOException          if any I/O error occurs.
    */
   public void stop() throws InterruptedException, IOException {
     reactorMain.shutdownNow();
@@ -114,15 +109,14 @@ public class NioReactor {
   }
 
   /**
-   * Registers a new channel (handle) with this reactor. Reactor will start waiting for events on this channel and
-   * notify of any events. While registering the channel the reactor uses {@link AbstractNioChannel#getInterestedOps()}
-   * to know about the interested operation of this channel.
-   * 
-   * @param channel
-   *          a new channel on which reactor will wait for events. The channel must be bound prior to being registered.
+   * Registers a new channel (handle) with this reactor. Reactor will start waiting for events on
+   * this channel and notify of any events. While registering the channel the reactor uses {@link
+   * AbstractNioChannel#getInterestedOps()} to know about the interested operation of this channel.
+   *
+   * @param channel a new channel on which reactor will wait for events. The channel must be bound
+   *                prior to being registered.
    * @return this
-   * @throws IOException
-   *           if any I/O error occurs.
+   * @throws IOException if any I/O error occurs.
    */
   public NioReactor registerChannel(AbstractNioChannel channel) throws IOException {
     SelectionKey key = channel.getJavaChannel().register(selector, channel.getInterestedOps());
@@ -143,8 +137,8 @@ public class NioReactor {
       processPendingCommands();
 
       /*
-       * Synchronous event de-multiplexing happens here, this is blocking call which returns when it is possible to
-       * initiate non-blocking operation on any of the registered channels.
+       * Synchronous event de-multiplexing happens here, this is blocking call which returns when it
+       * is possible to initiate non-blocking operation on any of the registered channels.
        */
       selector.select();
 
@@ -177,8 +171,8 @@ public class NioReactor {
   }
 
   /*
-   * Initiation dispatcher logic, it checks the type of event and notifier application specific event handler to handle
-   * the event.
+   * Initiation dispatcher logic, it checks the type of event and notifier application specific
+   * event handler to handle the event.
    */
   private void processKey(SelectionKey key) throws IOException {
     if (key.isAcceptable()) {
@@ -226,15 +220,14 @@ public class NioReactor {
   }
 
   /**
-   * Queues the change of operations request of a channel, which will change the interested operations of the channel
-   * sometime in future.
-   * <p>
-   * This is a non-blocking method and does not guarantee that the operations have changed when this method returns.
-   * 
-   * @param key
-   *          the key for which operations have to be changed.
-   * @param interestedOps
-   *          the new interest operations.
+   * Queues the change of operations request of a channel, which will change the interested
+   * operations of the channel sometime in future.
+   *
+   * <p>This is a non-blocking method and does not guarantee that the operations have changed when
+   * this method returns.
+   *
+   * @param key           the key for which operations have to be changed.
+   * @param interestedOps the new interest operations.
    */
   public void changeOps(SelectionKey key, int interestedOps) {
     pendingCommands.add(new ChangeKeyOpsCommand(key, interestedOps));
diff --git a/reactor/src/main/java/com/iluwatar/reactor/framework/NioServerSocketChannel.java b/reactor/src/main/java/com/iluwatar/reactor/framework/NioServerSocketChannel.java
index a56b5dfe9..7c52a95c3 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/framework/NioServerSocketChannel.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/framework/NioServerSocketChannel.java
@@ -23,9 +23,6 @@
 
 package com.iluwatar.reactor.framework;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.io.IOException;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
@@ -33,10 +30,12 @@ import java.nio.ByteBuffer;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.ServerSocketChannel;
 import java.nio.channels.SocketChannel;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
- * A wrapper over {@link NioServerSocketChannel} which can read and write data on a
- * {@link SocketChannel}.
+ * A wrapper over {@link NioServerSocketChannel} which can read and write data on a {@link
+ * SocketChannel}.
  */
 public class NioServerSocketChannel extends AbstractNioChannel {
 
@@ -47,11 +46,11 @@ public class NioServerSocketChannel extends AbstractNioChannel {
   /**
    * Creates a {@link ServerSocketChannel} which will bind at provided port and use
    * <code>handler</code> to handle incoming events on this channel.
-   * <p>
-   * Note the constructor does not bind the socket, {@link #bind()} method should be called for
+   *
+   * <p>Note the constructor does not bind the socket, {@link #bind()} method should be called for
    * binding the socket.
-   * 
-   * @param port the port on which channel will be bound to accept incoming connection requests.
+   *
+   * @param port    the port on which channel will be bound to accept incoming connection requests.
    * @param handler the handler that will handle incoming requests on this channel.
    * @throws IOException if any I/O error occurs.
    */
@@ -68,6 +67,8 @@ public class NioServerSocketChannel extends AbstractNioChannel {
   }
 
   /**
+   * Get server socket channel.
+   *
    * @return the underlying {@link ServerSocketChannel}.
    */
   @Override
@@ -94,7 +95,7 @@ public class NioServerSocketChannel extends AbstractNioChannel {
 
   /**
    * Binds TCP socket on the provided <code>port</code>.
-   * 
+   *
    * @throws IOException if any I/O error occurs.
    */
   @Override
diff --git a/reactor/src/main/java/com/iluwatar/reactor/framework/SameThreadDispatcher.java b/reactor/src/main/java/com/iluwatar/reactor/framework/SameThreadDispatcher.java
index a64acc069..0faff6793 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/framework/SameThreadDispatcher.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/framework/SameThreadDispatcher.java
@@ -29,18 +29,16 @@ import java.nio.channels.SelectionKey;
  * Dispatches the events in the context of caller thread. This implementation is a good fit for
  * small applications where there are limited clients. Using this implementation limits the
  * scalability because the I/O thread performs the application specific processing.
- * 
- * <p>
- * For better performance use {@link ThreadPoolDispatcher}.
- * 
+ *
+ * <p>For better performance use {@link ThreadPoolDispatcher}.
+ *
  * @see ThreadPoolDispatcher
  */
 public class SameThreadDispatcher implements Dispatcher {
 
   /**
-   * Dispatches the read event in the context of caller thread. <br>
-   * Note this is a blocking call. It returns only after the associated handler has handled the read
-   * event.
+   * Dispatches the read event in the context of caller thread. <br> Note this is a blocking call.
+   * It returns only after the associated handler has handled the read event.
    */
   @Override
   public void onChannelReadEvent(AbstractNioChannel channel, Object readObject, SelectionKey key) {
diff --git a/reactor/src/main/java/com/iluwatar/reactor/framework/ThreadPoolDispatcher.java b/reactor/src/main/java/com/iluwatar/reactor/framework/ThreadPoolDispatcher.java
index e4bd20cfd..b75f0f64d 100644
--- a/reactor/src/main/java/com/iluwatar/reactor/framework/ThreadPoolDispatcher.java
+++ b/reactor/src/main/java/com/iluwatar/reactor/framework/ThreadPoolDispatcher.java
@@ -39,7 +39,7 @@ public class ThreadPoolDispatcher implements Dispatcher {
 
   /**
    * Creates a pooled dispatcher with tunable pool size.
-   * 
+   *
    * @param poolSize number of pooled threads
    */
   public ThreadPoolDispatcher(int poolSize) {
@@ -48,9 +48,8 @@ public class ThreadPoolDispatcher implements Dispatcher {
 
   /**
    * Submits the work of dispatching the read event to worker pool, where it gets picked up by
-   * worker threads. <br>
-   * Note that this is a non-blocking call and returns immediately. It is not guaranteed that the
-   * event has been handled by associated handler.
+   * worker threads. <br> Note that this is a non-blocking call and returns immediately. It is not
+   * guaranteed that the event has been handled by associated handler.
    */
   @Override
   public void onChannelReadEvent(AbstractNioChannel channel, Object readObject, SelectionKey key) {
@@ -59,7 +58,7 @@ public class ThreadPoolDispatcher implements Dispatcher {
 
   /**
    * Stops the pool of workers.
-   * 
+   *
    * @throws InterruptedException if interrupted while stopping pool of workers.
    */
   @Override
diff --git a/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/App.java b/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/App.java
index 1232a73f7..f59ba10cc 100644
--- a/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/App.java
+++ b/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/App.java
@@ -28,26 +28,23 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.ThreadLocalRandom;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.IntStream;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * 
  * In a multiple thread applications, the threads may try to synchronize the shared resources
  * regardless of read or write operation. It leads to a low performance especially in a "read more
  * write less" system as indeed the read operations are thread-safe to another read operation.
- * <p>
- * Reader writer lock is a synchronization primitive that try to resolve this problem. This pattern
- * allows concurrent access for read-only operations, while write operations require exclusive
- * access. This means that multiple threads can read the data in parallel but an exclusive lock is
- * needed for writing or modifying data. When a writer is writing the data, all other writers or
- * readers will be blocked until the writer is finished writing.
- * 
- * <p>
- * This example use two mutex to demonstrate the concurrent access of multiple readers and writers.
- * 
- * 
+ *
+ * <p>Reader writer lock is a synchronization primitive that try to resolve this problem. This
+ * pattern allows concurrent access for read-only operations, while write operations require
+ * exclusive access. This means that multiple threads can read the data in parallel but an exclusive
+ * lock is needed for writing or modifying data. When a writer is writing the data, all other
+ * writers or readers will be blocked until the writer is finished writing.
+ *
+ * <p>This example use two mutex to demonstrate the concurrent access of multiple readers and
+ * writers.
+ *
  * @author hongshuwei@gmail.com
  */
 public class App {
@@ -55,27 +52,27 @@ public class App {
   private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
 
   /**
-   * Program entry point
-   * 
+   * Program entry point.
+   *
    * @param args command line args
    */
   public static void main(String[] args) {
 
     ExecutorService executeService = Executors.newFixedThreadPool(10);
     ReaderWriterLock lock = new ReaderWriterLock();
-    
+
     // Start writers
     IntStream.range(0, 5)
-        .forEach(i -> executeService.submit(new Writer("Writer " + i, lock.writeLock(), 
+        .forEach(i -> executeService.submit(new Writer("Writer " + i, lock.writeLock(),
             ThreadLocalRandom.current().nextLong(5000))));
     LOGGER.info("Writers added...");
 
     // Start readers
     IntStream.range(0, 5)
-        .forEach(i -> executeService.submit(new Reader("Reader " + i, lock.readLock(), 
+        .forEach(i -> executeService.submit(new Reader("Reader " + i, lock.readLock(),
             ThreadLocalRandom.current().nextLong(10))));
     LOGGER.info("Readers added...");
-    
+
     try {
       Thread.sleep(5000L);
     } catch (InterruptedException e) {
@@ -85,11 +82,10 @@ public class App {
 
     // Start readers
     IntStream.range(6, 10)
-        .forEach(i -> executeService.submit(new Reader("Reader " + i, lock.readLock(), 
+        .forEach(i -> executeService.submit(new Reader("Reader " + i, lock.readLock(),
             ThreadLocalRandom.current().nextLong(10))));
     LOGGER.info("More readers added...");
-    
-    
+
 
     // In the system console, it can see that the read operations are executed concurrently while
     // write operations are exclusive.
diff --git a/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/Reader.java b/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/Reader.java
index a4c7d0744..6d705de2f 100644
--- a/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/Reader.java
+++ b/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/Reader.java
@@ -24,12 +24,11 @@
 package com.iluwatar.reader.writer.lock;
 
 import java.util.concurrent.locks.Lock;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * Reader class, read when it acquired the read lock
+ * Reader class, read when it acquired the read lock.
  */
 public class Reader implements Runnable {
 
@@ -38,14 +37,14 @@ public class Reader implements Runnable {
   private Lock readLock;
 
   private String name;
-  
+
   private long readingTime;
 
   /**
-   * Create new Reader
-   * 
-   * @param name - Name of the thread owning the reader
-   * @param readLock - Lock for this reader
+   * Create new Reader.
+   *
+   * @param name        - Name of the thread owning the reader
+   * @param readLock    - Lock for this reader
    * @param readingTime - amount of time (in milliseconds) for this reader to engage reading
    */
   public Reader(String name, Lock readLock, long readingTime) {
@@ -53,11 +52,11 @@ public class Reader implements Runnable {
     this.readLock = readLock;
     this.readingTime = readingTime;
   }
-  
+
   /**
-   * Create new Reader who reads for 250ms
-   * 
-   * @param name - Name of the thread owning the reader
+   * Create new Reader who reads for 250ms.
+   *
+   * @param name     - Name of the thread owning the reader
    * @param readLock - Lock for this reader
    */
   public Reader(String name, Lock readLock) {
@@ -78,8 +77,7 @@ public class Reader implements Runnable {
   }
 
   /**
-   * Simulate the read operation
-   * 
+   * Simulate the read operation.
    */
   public void read() throws InterruptedException {
     LOGGER.info("{} begin", name);
diff --git a/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/ReaderWriterLock.java b/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/ReaderWriterLock.java
index 282503ea6..d578b0f21 100644
--- a/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/ReaderWriterLock.java
+++ b/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/ReaderWriterLock.java
@@ -29,18 +29,17 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReadWriteLock;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
  * Class responsible for control the access for reader or writer
- * 
- * Allows multiple readers to hold the lock at same time, but if any writer holds the lock then readers wait. If reader
- * holds the lock then writer waits. This lock is not fair.
+ *
+ * <p>Allows multiple readers to hold the lock at same time, but if any writer holds the lock then
+ * readers wait. If reader holds the lock then writer waits. This lock is not fair.
  */
 public class ReaderWriterLock implements ReadWriteLock {
-  
+
   private static final Logger LOGGER = LoggerFactory.getLogger(ReaderWriterLock.class);
 
 
@@ -50,13 +49,13 @@ public class ReaderWriterLock implements ReadWriteLock {
 
   /**
    * Global mutex is used to indicate that whether reader or writer gets the lock in the moment.
-   * <p>
-   * 1. When it contains the reference of {@link #readerLock}, it means that the lock is acquired by the reader, another
-   * reader can also do the read operation concurrently. <br>
-   * 2. When it contains the reference of reference of {@link #writerLock}, it means that the lock is acquired by the
-   * writer exclusively, no more reader or writer can get the lock.
-   * <p>
-   * This is the most important field in this class to control the access for reader/writer.
+   *
+   * <p>1. When it contains the reference of {@link #readerLock}, it means that the lock is
+   * acquired by the reader, another reader can also do the read operation concurrently. <br> 2.
+   * When it contains the reference of reference of {@link #writerLock}, it means that the lock is
+   * acquired by the writer exclusively, no more reader or writer can get the lock.
+   *
+   * <p>This is the most important field in this class to control the access for reader/writer.
    */
   private Set<Object> globalMutex = new HashSet<>();
 
@@ -74,22 +73,21 @@ public class ReaderWriterLock implements ReadWriteLock {
   }
 
   /**
-   * return true when globalMutex hold the reference of writerLock
+   * return true when globalMutex hold the reference of writerLock.
    */
   private boolean doesWriterOwnThisLock() {
     return globalMutex.contains(writerLock);
   }
 
   /**
-   * Nobody get the lock when globalMutex contains nothing
-   * 
+   * Nobody get the lock when globalMutex contains nothing.
    */
   private boolean isLockFree() {
     return globalMutex.isEmpty();
   }
 
   /**
-   * Reader Lock, can be access for more than one reader concurrently if no writer get the lock
+   * Reader Lock, can be access for more than one reader concurrently if no writer get the lock.
    */
   private class ReadLock implements Lock {
 
@@ -104,8 +102,8 @@ public class ReaderWriterLock implements ReadWriteLock {
     }
 
     /**
-     * Acquire the globalMutex lock on behalf of current and future concurrent readers. Make sure no writers currently
-     * owns the lock.
+     * Acquire the globalMutex lock on behalf of current and future concurrent readers. Make sure no
+     * writers currently owns the lock.
      */
     private void acquireForReaders() {
       // Try to get the globalMutex lock for the first reader
@@ -116,7 +114,8 @@ public class ReaderWriterLock implements ReadWriteLock {
           try {
             globalMutex.wait();
           } catch (InterruptedException e) {
-            LOGGER.info("InterruptedException while waiting for globalMutex in acquireForReaders", e);
+            LOGGER
+                .info("InterruptedException while waiting for globalMutex in acquireForReaders", e);
             Thread.currentThread().interrupt();
           }
         }
@@ -165,7 +164,7 @@ public class ReaderWriterLock implements ReadWriteLock {
   }
 
   /**
-   * Writer Lock, can only be accessed by one writer concurrently
+   * Writer Lock, can only be accessed by one writer concurrently.
    */
   private class WriteLock implements Lock {
 
diff --git a/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/Writer.java b/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/Writer.java
index afe93efd7..7a971b28b 100644
--- a/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/Writer.java
+++ b/reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/Writer.java
@@ -24,12 +24,11 @@
 package com.iluwatar.reader.writer.lock;
 
 import java.util.concurrent.locks.Lock;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * Writer class, write when it acquired the write lock
+ * Writer class, write when it acquired the write lock.
  */
 public class Writer implements Runnable {
 
@@ -38,24 +37,24 @@ public class Writer implements Runnable {
   private Lock writeLock;
 
   private String name;
-  
+
   private long writingTime;
 
   /**
-   * Create new Writer who writes for 250ms
-   * 
-   * @param name - Name of the thread owning the writer
+   * Create new Writer who writes for 250ms.
+   *
+   * @param name      - Name of the thread owning the writer
    * @param writeLock - Lock for this writer
    */
   public Writer(String name, Lock writeLock) {
     this(name, writeLock, 250L);
   }
-  
+
   /**
-   * Create new Writer
-   * 
-   * @param name - Name of the thread owning the writer
-   * @param writeLock - Lock for this writer
+   * Create new Writer.
+   *
+   * @param name        - Name of the thread owning the writer
+   * @param writeLock   - Lock for this writer
    * @param writingTime - amount of time (in milliseconds) for this reader to engage writing
    */
   public Writer(String name, Lock writeLock, long writingTime) {
@@ -77,9 +76,9 @@ public class Writer implements Runnable {
       writeLock.unlock();
     }
   }
-  
+
   /**
-   * Simulate the write operation
+   * Simulate the write operation.
    */
   public void write() throws InterruptedException {
     LOGGER.info("{} begin", name);
diff --git a/repository/src/main/java/com/iluwatar/repository/App.java b/repository/src/main/java/com/iluwatar/repository/App.java
index 0ecafd030..ac932b815 100644
--- a/repository/src/main/java/com/iluwatar/repository/App.java
+++ b/repository/src/main/java/com/iluwatar/repository/App.java
@@ -25,7 +25,6 @@ package com.iluwatar.repository;
 
 import java.util.List;
 import java.util.Optional;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.context.support.ClassPathXmlApplicationContext;
@@ -38,8 +37,8 @@ import org.springframework.context.support.ClassPathXmlApplicationContext;
  * query construction code is concentrated. This becomes more important when there are a large
  * number of domain classes or heavy querying. In these cases particularly, adding this layer helps
  * minimize duplicate query logic.
- * <p>
- * In this example we utilize Spring Data to automatically generate a repository for us from the
+ *
+ * <p>In this example we utilize Spring Data to automatically generate a repository for us from the
  * {@link Person} domain object. Using the {@link PersonRepository} we perform CRUD operations on
  * the entity, moreover, the query by {@link org.springframework.data.jpa.domain.Specification} are
  * also performed. Underneath we have configured in-memory H2 database for which schema is created
@@ -50,10 +49,9 @@ public class App {
   private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
 
   /**
-   * Program entry point
-   * 
-   * @param args
-   *          command line args
+   * Program entry point.
+   *
+   * @param args command line args
    */
   public static void main(String[] args) {
 
@@ -107,7 +105,7 @@ public class App {
     }
 
     repository.deleteAll();
-    
+
     context.close();
 
   }
diff --git a/repository/src/main/java/com/iluwatar/repository/AppConfig.java b/repository/src/main/java/com/iluwatar/repository/AppConfig.java
index f4f46be88..197205773 100644
--- a/repository/src/main/java/com/iluwatar/repository/AppConfig.java
+++ b/repository/src/main/java/com/iluwatar/repository/AppConfig.java
@@ -27,9 +27,7 @@ import java.sql.SQLException;
 import java.util.List;
 import java.util.Optional;
 import java.util.Properties;
-
 import javax.sql.DataSource;
-
 import org.apache.commons.dbcp.BasicDataSource;
 import org.hibernate.jpa.HibernatePersistenceProvider;
 import org.slf4j.Logger;
@@ -42,9 +40,7 @@ import org.springframework.orm.jpa.JpaTransactionManager;
 import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
 
 /**
- * This is the same example as in {@link App} but with annotations based 
- * configuration for Spring.
- *
+ * This is the same example as in {@link App} but with annotations based configuration for Spring.
  */
 @EnableJpaRepositories
 @SpringBootConfiguration
@@ -53,8 +49,8 @@ public class AppConfig {
   private static final Logger LOGGER = LoggerFactory.getLogger(AppConfig.class);
 
   /**
-   * Creation of H2 db
-   * 
+   * Creation of H2 db.
+   *
    * @return A new Instance of DataSource
    */
   @Bean(destroyMethod = "close")
@@ -68,11 +64,12 @@ public class AppConfig {
   }
 
   /**
-   * Factory to create a especific instance of Entity Manager
+   * Factory to create a especific instance of Entity Manager.
    */
   @Bean
   public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
-    LocalContainerEntityManagerFactoryBean entityManager = new LocalContainerEntityManagerFactoryBean();
+    LocalContainerEntityManagerFactoryBean entityManager =
+        new LocalContainerEntityManagerFactoryBean();
     entityManager.setDataSource(dataSource());
     entityManager.setPackagesToScan("com.iluwatar");
     entityManager.setPersistenceProvider(new HibernatePersistenceProvider());
@@ -82,7 +79,7 @@ public class AppConfig {
   }
 
   /**
-   * Properties for Jpa
+   * Properties for Jpa.
    */
   private static Properties jpaProperties() {
     Properties properties = new Properties();
@@ -92,7 +89,7 @@ public class AppConfig {
   }
 
   /**
-   * Get transaction manager
+   * Get transaction manager.
    */
   @Bean
   public JpaTransactionManager transactionManager() throws SQLException {
@@ -102,10 +99,9 @@ public class AppConfig {
   }
 
   /**
-   * Program entry point
-   * 
-   * @param args
-   *          command line args
+   * Program entry point.
+   *
+   * @param args command line args
    */
   public static void main(String[] args) {
 
diff --git a/repository/src/main/java/com/iluwatar/repository/Person.java b/repository/src/main/java/com/iluwatar/repository/Person.java
index ded5b8cfa..e83f0ce46 100644
--- a/repository/src/main/java/com/iluwatar/repository/Person.java
+++ b/repository/src/main/java/com/iluwatar/repository/Person.java
@@ -28,9 +28,7 @@ import javax.persistence.GeneratedValue;
 import javax.persistence.Id;
 
 /**
- * 
- * Person entity
- *
+ * Person entity.
  */
 @Entity
 public class Person {
@@ -47,7 +45,7 @@ public class Person {
   }
 
   /**
-   * Constructor
+   * Constructor.
    */
   public Person(String name, String surname, int age) {
     this.name = name;
diff --git a/repository/src/main/java/com/iluwatar/repository/PersonRepository.java b/repository/src/main/java/com/iluwatar/repository/PersonRepository.java
index e181d19b5..2bdd0feb7 100644
--- a/repository/src/main/java/com/iluwatar/repository/PersonRepository.java
+++ b/repository/src/main/java/com/iluwatar/repository/PersonRepository.java
@@ -28,9 +28,7 @@ import org.springframework.data.repository.CrudRepository;
 import org.springframework.stereotype.Repository;
 
 /**
- * 
- * Person repository
- *
+ * Person repository.
  */
 @Repository
 public interface PersonRepository
diff --git a/repository/src/main/java/com/iluwatar/repository/PersonSpecifications.java b/repository/src/main/java/com/iluwatar/repository/PersonSpecifications.java
index 5a14985c9..149c2488e 100644
--- a/repository/src/main/java/com/iluwatar/repository/PersonSpecifications.java
+++ b/repository/src/main/java/com/iluwatar/repository/PersonSpecifications.java
@@ -27,16 +27,15 @@ import javax.persistence.criteria.CriteriaBuilder;
 import javax.persistence.criteria.CriteriaQuery;
 import javax.persistence.criteria.Predicate;
 import javax.persistence.criteria.Root;
-
 import org.springframework.data.jpa.domain.Specification;
 
 /**
- * Helper class, includes vary Specification as the abstraction of sql query criteria
+ * Helper class, includes vary Specification as the abstraction of sql query criteria.
  */
 public class PersonSpecifications {
 
   /**
-   * Specifications stating the Between (From - To) Age Specification
+   * Specifications stating the Between (From - To) Age Specification.
    */
   public static class AgeBetweenSpec implements Specification<Person> {
 
@@ -59,8 +58,7 @@ public class PersonSpecifications {
   }
 
   /**
-   * Name specification
-   *
+   * Name specification.
    */
   public static class NameEqualSpec implements Specification<Person> {
 
@@ -71,7 +69,7 @@ public class PersonSpecifications {
     }
 
     /**
-     * Get predicate
+     * Get predicate.
      */
     public Predicate toPredicate(Root<Person> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
 
diff --git a/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/App.java b/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/App.java
index fc67465a7..293675e99 100644
--- a/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/App.java
+++ b/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/App.java
@@ -27,31 +27,30 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * 
  * Resource Acquisition Is Initialization pattern was developed for exception safe resource
  * management by C++ creator Bjarne Stroustrup.
- * <p>
- * In RAII resource is tied to object lifetime: resource allocation is done during object creation
- * while resource deallocation is done during object destruction.
- * <p>
- * In Java RAII is achieved with try-with-resources statement and interfaces {@link java.io.Closeable} and
- * {@link AutoCloseable}. The try-with-resources statement ensures that each resource is closed at
- * the end of the statement. Any object that implements {@link java.lang.AutoCloseable}, which
- * includes all objects which implement {@link java.io.Closeable}, can be used as a resource.
  *
- * In this example, {@link SlidingDoor} implements {@link AutoCloseable} and {@link TreasureChest}
- * implements {@link java.io.Closeable}. Running the example, we can observe that both resources are
- * automatically closed.
- * <p>
- * http://docs.oracle.com/javase/7/docs/technotes/guides/language/try-with-resources.html
+ * <p>In RAII resource is tied to object lifetime: resource allocation is done during object
+ * creation while resource deallocation is done during object destruction.
  *
+ * <p>In Java RAII is achieved with try-with-resources statement and interfaces {@link
+ * java.io.Closeable} and {@link AutoCloseable}. The try-with-resources statement ensures that each
+ * resource is closed at the end of the statement. Any object that implements {@link
+ * java.lang.AutoCloseable}, which includes all objects which implement {@link java.io.Closeable},
+ * can be used as a resource.
+ *
+ * <p>In this example, {@link SlidingDoor} implements {@link AutoCloseable} and {@link
+ * TreasureChest} implements {@link java.io.Closeable}. Running the example, we can observe that
+ * both resources are automatically closed.
+ *
+ * <p>http://docs.oracle.com/javase/7/docs/technotes/guides/language/try-with-resources.html
  */
 public class App {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
 
   /**
-   * Program entry point
+   * Program entry point.
    */
   public static void main(String[] args) throws Exception {
 
diff --git a/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/SlidingDoor.java b/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/SlidingDoor.java
index 47c36a77f..d890eb4c3 100644
--- a/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/SlidingDoor.java
+++ b/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/SlidingDoor.java
@@ -27,9 +27,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * 
- * SlidingDoor resource
- *
+ * SlidingDoor resource.
  */
 public class SlidingDoor implements AutoCloseable {
 
diff --git a/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/TreasureChest.java b/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/TreasureChest.java
index d8adf2ed4..26eab1405 100644
--- a/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/TreasureChest.java
+++ b/resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/TreasureChest.java
@@ -23,16 +23,13 @@
 
 package com.iluwatar.resource.acquisition.is.initialization;
 
+import java.io.Closeable;
+import java.io.IOException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.io.Closeable;
-import java.io.IOException;
-
 /**
- * 
- * TreasureChest resource
- *
+ * TreasureChest resource.
  */
 public class TreasureChest implements Closeable {
 
diff --git a/retry/src/main/java/com/iluwatar/retry/App.java b/retry/src/main/java/com/iluwatar/retry/App.java
index 5eb78125c..594c48295 100644
--- a/retry/src/main/java/com/iluwatar/retry/App.java
+++ b/retry/src/main/java/com/iluwatar/retry/App.java
@@ -27,34 +27,35 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * The <em>Retry</em> pattern enables applications to handle potentially recoverable failures from 
- * the environment if the business requirements and nature of the failures allow it. By retrying 
+ * The <em>Retry</em> pattern enables applications to handle potentially recoverable failures from
+ * the environment if the business requirements and nature of the failures allow it. By retrying
  * failed operations on external dependencies, the application may maintain stability and minimize
  * negative impact on the user experience.
- * <p>
- * In our example, we have the {@link BusinessOperation} interface as an abstraction over
- * all operations that our application performs involving remote systems. The calling code should
- * remain decoupled from implementations. 
- * <p>
- * {@link FindCustomer} is a business operation that looks up a customer's record and returns 
- * its ID. Imagine its job is performed by looking up the customer in our local database and 
- * returning its ID. We can pass {@link CustomerNotFoundException} as one of its 
- * {@link FindCustomer#FindCustomer(java.lang.String, com.iluwatar.retry.BusinessException...) 
- * constructor parameters} in order to simulate not finding the customer.
- * <p>
- * Imagine that, lately, this operation has experienced intermittent failures due to some weird 
- * corruption and/or locking in the data. After retrying a few times the customer is found. The 
- * database is still, however, expected to always be available.  While a definitive solution is 
- * found to the problem, our engineers advise us to retry the operation a set number
- * of times with a set delay between retries, although not too many retries otherwise the end user
- * will be left waiting for a long time, while delays that are too short will not allow the database
- * to recover from the load. 
- * <p>
- * To keep the calling code as decoupled as possible from this workaround, we have implemented the
- * retry mechanism as a {@link BusinessOperation} named {@link Retry}.
- * 
+ *
+ * <p>In our example, we have the {@link BusinessOperation} interface as an abstraction over all
+ * operations that our application performs involving remote systems. The calling code should remain
+ * decoupled from implementations.
+ *
+ * <p>{@link FindCustomer} is a business operation that looks up a customer's record and returns
+ * its ID. Imagine its job is performed by looking up the customer in our local database and
+ * returning its ID. We can pass {@link CustomerNotFoundException} as one of its {@link
+ * FindCustomer#FindCustomer(java.lang.String, com.iluwatar.retry.BusinessException...) constructor
+ * parameters} in order to simulate not finding the customer.
+ *
+ * <p>Imagine that, lately, this operation has experienced intermittent failures due to some weird
+ * corruption and/or locking in the data. After retrying a few times the customer is found. The
+ * database is still, however, expected to always be available.  While a definitive solution is
+ * found to the problem, our engineers advise us to retry the operation a set number of times with a
+ * set delay between retries, although not too many retries otherwise the end user will be left
+ * waiting for a long time, while delays that are too short will not allow the database to recover
+ * from the load.
+ *
+ * <p>To keep the calling code as decoupled as possible from this workaround, we have implemented
+ * the retry mechanism as a {@link BusinessOperation} named {@link Retry}.
+ *
  * @author George Aristy (george.aristy@gmail.com)
- * @see <a href="https://docs.microsoft.com/en-us/azure/architecture/patterns/retry">Retry pattern (Microsoft Azure Docs)</a>
+ * @see <a href="https://docs.microsoft.com/en-us/azure/architecture/patterns/retry">Retry pattern
+ *     (Microsoft Azure Docs)</a>
  */
 public final class App {
   private static final Logger LOG = LoggerFactory.getLogger(App.class);
@@ -62,7 +63,7 @@ public final class App {
 
   /**
    * Entry point.
-   * 
+   *
    * @param args not used
    * @throws Exception not expected
    */
@@ -99,22 +100,22 @@ public final class App {
     final String customerId = op.perform();
     LOG.info(String.format(
         "However, retrying the operation while ignoring a recoverable error will eventually yield "
-        + "the result %s after a number of attempts %s", customerId, retry.attempts()
+            + "the result %s after a number of attempts %s", customerId, retry.attempts()
     ));
   }
-  
+
   private static void errorWithRetryExponentialBackoff() throws Exception {
     final RetryExponentialBackoff<String> retry = new RetryExponentialBackoff<>(
         new FindCustomer("123", new CustomerNotFoundException("not found")),
         6,  //6 attempts
         30000, //30 s max delay between attempts
         e -> CustomerNotFoundException.class.isAssignableFrom(e.getClass())
-        );
+    );
     op = retry;
     final String customerId = op.perform();
     LOG.info(String.format(
-                "However, retrying the operation while ignoring a recoverable error will eventually yield "
-                        + "the result %s after a number of attempts %s", customerId, retry.attempts()
-        ));
+        "However, retrying the operation while ignoring a recoverable error will eventually yield "
+            + "the result %s after a number of attempts %s", customerId, retry.attempts()
+    ));
   }
 }
diff --git a/retry/src/main/java/com/iluwatar/retry/BusinessException.java b/retry/src/main/java/com/iluwatar/retry/BusinessException.java
index 2da1cca8a..397a4623b 100644
--- a/retry/src/main/java/com/iluwatar/retry/BusinessException.java
+++ b/retry/src/main/java/com/iluwatar/retry/BusinessException.java
@@ -24,10 +24,10 @@
 package com.iluwatar.retry;
 
 /**
- * The top-most type in our exception hierarchy that signifies that an unexpected error 
- * condition occurred. Its use is reserved as a "catch-all" for cases where no other subtype 
- * captures the specificity of the error condition in question. Calling code is not expected to 
- * be able to handle this error and should be reported to the maintainers immediately.
+ * The top-most type in our exception hierarchy that signifies that an unexpected error condition
+ * occurred. Its use is reserved as a "catch-all" for cases where no other subtype captures the
+ * specificity of the error condition in question. Calling code is not expected to be able to handle
+ * this error and should be reported to the maintainers immediately.
  *
  * @author George Aristy (george.aristy@gmail.com)
  */
@@ -35,8 +35,8 @@ public class BusinessException extends Exception {
   private static final long serialVersionUID = 6235833142062144336L;
 
   /**
-   * Ctor
-   * 
+   * Ctor.
+   *
    * @param message the error message
    */
   public BusinessException(String message) {
diff --git a/retry/src/main/java/com/iluwatar/retry/BusinessOperation.java b/retry/src/main/java/com/iluwatar/retry/BusinessOperation.java
index a829ff541..a67240d3c 100644
--- a/retry/src/main/java/com/iluwatar/retry/BusinessOperation.java
+++ b/retry/src/main/java/com/iluwatar/retry/BusinessOperation.java
@@ -26,18 +26,18 @@ package com.iluwatar.retry;
 /**
  * Performs some business operation.
  *
- * @author George Aristy (george.aristy@gmail.com)
  * @param <T> the return type
+ * @author George Aristy (george.aristy@gmail.com)
  */
 @FunctionalInterface
 public interface BusinessOperation<T> {
   /**
    * Performs some business operation, returning a value {@code T} if successful, otherwise throwing
    * an exception if an error occurs.
-   * 
+   *
    * @return the return value
    * @throws BusinessException if the operation fails. Implementations are allowed to throw more
-   *     specific subtypes depending on the error conditions
+   *                           specific subtypes depending on the error conditions
    */
   T perform() throws BusinessException;
 }
diff --git a/retry/src/main/java/com/iluwatar/retry/CustomerNotFoundException.java b/retry/src/main/java/com/iluwatar/retry/CustomerNotFoundException.java
index c0a9ca434..3826fe0e1 100644
--- a/retry/src/main/java/com/iluwatar/retry/CustomerNotFoundException.java
+++ b/retry/src/main/java/com/iluwatar/retry/CustomerNotFoundException.java
@@ -24,10 +24,11 @@
 package com.iluwatar.retry;
 
 /**
- * Indicates that the customer was not found. 
- * <p>
- * The severity of this error is bounded by its context: was the search for the customer triggered
- * by an input from some end user, or were the search parameters pulled from your database?
+ * Indicates that the customer was not found.
+ *
+ * <p>The severity of this error is bounded by its context: was the search for the customer
+ * triggered by an input from some end user, or were the search parameters pulled from your
+ * database?
  *
  * @author George Aristy (george.aristy@gmail.com)
  */
@@ -36,7 +37,7 @@ public final class CustomerNotFoundException extends BusinessException {
 
   /**
    * Ctor.
-   * 
+   *
    * @param message the error message
    */
   public CustomerNotFoundException(String message) {
diff --git a/retry/src/main/java/com/iluwatar/retry/DatabaseNotAvailableException.java b/retry/src/main/java/com/iluwatar/retry/DatabaseNotAvailableException.java
index 02cbc6521..37fcecf32 100644
--- a/retry/src/main/java/com/iluwatar/retry/DatabaseNotAvailableException.java
+++ b/retry/src/main/java/com/iluwatar/retry/DatabaseNotAvailableException.java
@@ -33,7 +33,7 @@ public final class DatabaseNotAvailableException extends BusinessException {
 
   /**
    * Ctor.
-   * 
+   *
    * @param message the error message
    */
   public DatabaseNotAvailableException(String message) {
diff --git a/retry/src/main/java/com/iluwatar/retry/FindCustomer.java b/retry/src/main/java/com/iluwatar/retry/FindCustomer.java
index e5013f50e..af3e5469a 100644
--- a/retry/src/main/java/com/iluwatar/retry/FindCustomer.java
+++ b/retry/src/main/java/com/iluwatar/retry/FindCustomer.java
@@ -29,9 +29,9 @@ import java.util.List;
 
 /**
  * Finds a customer, returning its ID from our records.
- * <p>
- * This is an imaginary operation that, for some imagined input, returns the ID for a customer. 
- * However, this is a "flaky" operation that is supposed to fail intermittently, but for the 
+ *
+ * <p>This is an imaginary operation that, for some imagined input, returns the ID for a customer.
+ * However, this is a "flaky" operation that is supposed to fail intermittently, but for the
  * purposes of this example it fails in a programmed way depending on the constructor parameters.
  *
  * @author George Aristy (george.aristy@gmail.com)
@@ -42,15 +42,15 @@ public final class FindCustomer implements BusinessOperation<String> {
 
   /**
    * Ctor.
-   * 
+   *
    * @param customerId the final result of the remote operation
-   * @param errors the errors to throw before returning {@code customerId}
+   * @param errors     the errors to throw before returning {@code customerId}
    */
   public FindCustomer(String customerId, BusinessException... errors) {
     this.customerId = customerId;
     this.errors = new ArrayDeque<>(List.of(errors));
   }
-  
+
   @Override
   public String perform() throws BusinessException {
     if (!this.errors.isEmpty()) {
diff --git a/retry/src/main/java/com/iluwatar/retry/Retry.java b/retry/src/main/java/com/iluwatar/retry/Retry.java
index 7f188cb8f..f54c51301 100644
--- a/retry/src/main/java/com/iluwatar/retry/Retry.java
+++ b/retry/src/main/java/com/iluwatar/retry/Retry.java
@@ -33,8 +33,8 @@ import java.util.function.Predicate;
 /**
  * Decorates {@link BusinessOperation business operation} with "retry" capabilities.
  *
- * @author George Aristy (george.aristy@gmail.com)
  * @param <T> the remote op's return type
+ * @author George Aristy (george.aristy@gmail.com)
  */
 public final class Retry<T> implements BusinessOperation<T> {
   private final BusinessOperation<T> op;
@@ -46,18 +46,18 @@ public final class Retry<T> implements BusinessOperation<T> {
 
   /**
    * Ctor.
-   * 
-   * @param op the {@link BusinessOperation} to retry
+   *
+   * @param op          the {@link BusinessOperation} to retry
    * @param maxAttempts number of times to retry
-   * @param delay delay (in milliseconds) between attempts
+   * @param delay       delay (in milliseconds) between attempts
    * @param ignoreTests tests to check whether the remote exception can be ignored. No exceptions
-   *     will be ignored if no tests are given
+   *                    will be ignored if no tests are given
    */
   @SafeVarargs
   public Retry(
-      BusinessOperation<T> op, 
-      int maxAttempts, 
-      long delay, 
+      BusinessOperation<T> op,
+      int maxAttempts,
+      long delay,
       Predicate<Exception>... ignoreTests
   ) {
     this.op = op;
@@ -70,7 +70,7 @@ public final class Retry<T> implements BusinessOperation<T> {
 
   /**
    * The errors encountered while retrying, in the encounter order.
-   * 
+   *
    * @return the errors encountered while retrying
    */
   public List<Exception> errors() {
@@ -79,7 +79,7 @@ public final class Retry<T> implements BusinessOperation<T> {
 
   /**
    * The number of retries performed.
-   * 
+   *
    * @return the number of retries performed
    */
   public int attempts() {
@@ -93,7 +93,7 @@ public final class Retry<T> implements BusinessOperation<T> {
         return this.op.perform();
       } catch (BusinessException e) {
         this.errors.add(e);
-        
+
         if (this.attempts.incrementAndGet() >= this.maxAttempts || !this.test.test(e)) {
           throw e;
         }
@@ -104,7 +104,6 @@ public final class Retry<T> implements BusinessOperation<T> {
           //ignore
         }
       }
-    }
-    while (true);
+    } while (true);
   }
 }
diff --git a/retry/src/main/java/com/iluwatar/retry/RetryExponentialBackoff.java b/retry/src/main/java/com/iluwatar/retry/RetryExponentialBackoff.java
index 91dc0d6b2..c074f9cd4 100644
--- a/retry/src/main/java/com/iluwatar/retry/RetryExponentialBackoff.java
+++ b/retry/src/main/java/com/iluwatar/retry/RetryExponentialBackoff.java
@@ -34,8 +34,8 @@ import java.util.function.Predicate;
 /**
  * Decorates {@link BusinessOperation business operation} with "retry" capabilities.
  *
- * @author George Aristy (george.aristy@gmail.com)
  * @param <T> the remote op's return type
+ * @author George Aristy (george.aristy@gmail.com)
  */
 public final class RetryExponentialBackoff<T> implements BusinessOperation<T> {
   private static final Random RANDOM = new Random();
@@ -46,20 +46,20 @@ public final class RetryExponentialBackoff<T> implements BusinessOperation<T> {
   private final Predicate<Exception> test;
   private final List<Exception> errors;
 
-    /**
-     * Ctor.
-     *
-     * @param op the {@link BusinessOperation} to retry
-     * @param maxAttempts number of times to retry
-     * @param ignoreTests tests to check whether the remote exception can be ignored. No exceptions
-     *     will be ignored if no tests are given
-     */
+  /**
+   * Ctor.
+   *
+   * @param op          the {@link BusinessOperation} to retry
+   * @param maxAttempts number of times to retry
+   * @param ignoreTests tests to check whether the remote exception can be ignored. No exceptions
+   *                    will be ignored if no tests are given
+   */
   @SafeVarargs
   public RetryExponentialBackoff(
-            BusinessOperation<T> op,
-            int maxAttempts,
-            long maxDelay,
-            Predicate<Exception>... ignoreTests
+      BusinessOperation<T> op,
+      int maxAttempts,
+      long maxDelay,
+      Predicate<Exception>... ignoreTests
   ) {
     this.op = op;
     this.maxAttempts = maxAttempts;
@@ -69,20 +69,20 @@ public final class RetryExponentialBackoff<T> implements BusinessOperation<T> {
     this.errors = new ArrayList<>();
   }
 
-    /**
-     * The errors encountered while retrying, in the encounter order.
-     *
-     * @return the errors encountered while retrying
-     */
+  /**
+   * The errors encountered while retrying, in the encounter order.
+   *
+   * @return the errors encountered while retrying
+   */
   public List<Exception> errors() {
     return Collections.unmodifiableList(this.errors);
   }
 
-    /**
-     * The number of retries performed.
-     *
-     * @return the number of retries performed
-     */
+  /**
+   * The number of retries performed.
+   *
+   * @return the number of retries performed
+   */
   public int attempts() {
     return this.attempts.intValue();
   }
@@ -107,8 +107,7 @@ public final class RetryExponentialBackoff<T> implements BusinessOperation<T> {
           //ignore
         }
       }
-    }
-    while (true);
+    } while (true);
   }
 }