Fix #69: Coverity defects (#70)

* Fix possible NPE in HttpServerHandler and pointless variable assignment in PayloadConfig

* Grammar fix in HttpServerHandler

* Apply spotless

* Try/catch the remote address instead of checking if the channel is active

* Remove unused remoteAddress from RelpConversion

src/main/java/com/teragrep/lsh_01/HttpServerHandler.java

@@ -29,8 +29,9 @@
 import io.netty.handler.codec.http.HttpHeaderNames;
 import io.netty.handler.codec.http.HttpResponseStatus;
 import io.netty.handler.codec.http.HttpVersion;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
-import java.net.InetSocketAddress;
 import java.util.concurrent.ThreadPoolExecutor;
 
 import static io.netty.buffer.Unpooled.copiedBuffer;
@@ -40,6 +41,8 @@
  */
 public class HttpServerHandler extends SimpleChannelInboundHandler<FullHttpRequest> {
 
+    private final static Logger LOGGER = LogManager.getLogger(HttpServerHandler.class);
+
     private final IMessageHandler messageHandler;
     private final ThreadPoolExecutor executorGroup;
     private final HttpResponseStatus responseStatus;
@@ -59,12 +62,10 @@ public HttpServerHandler(
 
     @Override
     public void channelRead0(ChannelHandlerContext ctx, FullHttpRequest msg) {
-        final String remoteAddress = ((InetSocketAddress) ctx.channel().remoteAddress()).getAddress().getHostAddress();
         msg.retain();
         final MessageProcessor messageProcessor = new MessageProcessor(
                 ctx,
                 msg,
-                remoteAddress,
                 messageHandler,
                 responseStatus,
                 internalEndpointUrlConfig

src/main/java/com/teragrep/lsh_01/IMessageHandler.java

@@ -31,11 +31,10 @@ public interface IMessageHandler {
     /**
      * This is triggered on every new message parsed by the http handler and should be executed in the ruby world.
      *
-     * @param remoteAddress
      * @param headers
      * @param body
      */
-    boolean onNewMessage(String remoteAddress, Subject subject, Map<String, String> headers, String body);
+    boolean onNewMessage(Subject subject, Map<String, String> headers, String body);
 
     /**
      * @param token

src/main/java/com/teragrep/lsh_01/MessageProcessor.java

@@ -45,7 +45,6 @@ public class MessageProcessor implements RejectableRunnable {
 
     private final ChannelHandlerContext ctx;
     private final FullHttpRequest req;
-    private final String remoteAddress;
     private final IMessageHandler messageHandler;
     private final HttpResponseStatus responseStatus;
     private final InternalEndpointUrlConfig internalEndpointUrlConfig;
@@ -56,14 +55,12 @@ public class MessageProcessor implements RejectableRunnable {
     MessageProcessor(
             ChannelHandlerContext ctx,
             FullHttpRequest req,
-            String remoteAddress,
             IMessageHandler messageHandler,
             HttpResponseStatus responseStatus,
             InternalEndpointUrlConfig internalEndpointUrlConfig
     ) {
         this.ctx = ctx;
         this.req = req;
-        this.remoteAddress = remoteAddress;
         this.messageHandler = messageHandler;
         this.responseStatus = responseStatus;
         this.internalEndpointUrlConfig = internalEndpointUrlConfig;
@@ -137,7 +134,7 @@ private boolean isInternalEndpoint() {
     private FullHttpResponse processMessage(Subject subject) {
         final Map<String, String> formattedHeaders = formatHeaders(req.headers());
         final String body = req.content().toString(UTF8_CHARSET);
-        if (messageHandler.onNewMessage(remoteAddress, subject, formattedHeaders, body)) {
+        if (messageHandler.onNewMessage(subject, formattedHeaders, body)) {
             return generateResponse(messageHandler.responseHeaders());
         }
         else {

src/main/java/com/teragrep/lsh_01/RelpConversion.java

@@ -64,7 +64,7 @@ public RelpConversion(
         this.payloadConfig = payloadConfig;
     }
 
-    public boolean onNewMessage(String remoteAddress, Subject subject, Map<String, String> headers, String body) {
+    public boolean onNewMessage(Subject subject, Map<String, String> headers, String body) {
         try {
             if (payloadConfig.splitEnabled) {
                 Pattern splitPattern = Pattern.compile(payloadConfig.splitRegex);

src/main/java/com/teragrep/lsh_01/config/PayloadConfig.java

@@ -39,7 +39,7 @@ public PayloadConfig() {
     public void validate() {
         if (splitEnabled) {
             try {
-                Pattern splitPattern = Pattern.compile(splitRegex);
+                Pattern.compile(splitRegex);
             }
             catch (PatternSyntaxException e) {
                 throw new IllegalArgumentException(