Increased use of log4j2 readability.

src/main/java/org/logstash/beats/BeatsHandler.java

@@ -1,5 +1,9 @@
 package org.logstash.beats;
 
+import org.apache.logging.log4j.Level;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.SimpleChannelInboundHandler;
 import io.netty.util.AttributeKey;
@@ -10,7 +14,8 @@
 import javax.net.ssl.SSLHandshakeException;
 
 public class BeatsHandler extends SimpleChannelInboundHandler<Batch> {
-    private final static Logger logger = LogManager.getLogger(BeatsHandler.class);
+
+    private final static Logger logger = LogManager.getLogger();
     private final IMessageListener messageListener;
     private ChannelHandlerContext context;
 
@@ -22,33 +27,25 @@ public BeatsHandler(IMessageListener listener) {
     @Override
     public void channelActive(final ChannelHandlerContext ctx) throws Exception {
 	    context = ctx;
-        if (logger.isTraceEnabled()){
-            logger.trace(format("Channel Active"));
-        }
+        logger.trace("{}", () -> format("Channel Active"));
         super.channelActive(ctx);
         messageListener.onNewConnection(ctx);
     }
 
     @Override
     public void channelInactive(ChannelHandlerContext ctx) throws Exception {
         super.channelInactive(ctx);
-        if (logger.isTraceEnabled()){
-            logger.trace(format("Channel Inactive"));
-        }
+        logger.trace("{}", () -> format("Channel Inactive"));
         messageListener.onConnectionClose(ctx);
     }
 
 
     @Override
     public void channelRead0(ChannelHandlerContext ctx, Batch batch) throws Exception {
-        if(logger.isDebugEnabled()) {
-            logger.debug(format("Received a new payload"));
-        }
+        logger.debug("{}", () -> format("Received a new payload"));
         try {
             for (Message message : batch) {
-                if (logger.isDebugEnabled()) {
-                    logger.debug(format("Sending a new message for the listener, sequence: " + message.getSequence()));
-                }
+                logger.debug("{}", () -> format("Sending a new message for the listener, sequence: " + message.getSequence()));
                 messageListener.onNewMessage(ctx, message);
 
                 if (needAck(message)) {
@@ -58,9 +55,9 @@ public void channelRead0(ChannelHandlerContext ctx, Batch batch) throws Exceptio
         }finally{
             //this channel is done processing this payload, instruct the connection handler to stop sending TCP keep alive
             ctx.channel().attr(ConnectionHandler.CHANNEL_SEND_KEEP_ALIVE).get().set(false);
-            if (logger.isDebugEnabled()) {
-                logger.debug("{}: batches pending: {}", ctx.channel().id().asShortText(),ctx.channel().attr(ConnectionHandler.CHANNEL_SEND_KEEP_ALIVE).get().get());
-            }
+            logger.debug("{}: batches pending: {}",
+                         () -> ctx.channel().id().asShortText(),
+                         () -> ctx.channel().attr(ConnectionHandler.CHANNEL_SEND_KEEP_ALIVE).get().get());
             batch.release();
             ctx.flush();
         }
@@ -83,11 +80,9 @@ public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws E
             }
             String causeMessage = cause.getMessage() == null ? cause.getClass().toString() : cause.getMessage();
 
-            if (logger.isDebugEnabled()){
-                logger.debug(format("Handling exception: " + causeMessage), cause);
-            }
-            logger.info(format("Handling exception: " + causeMessage));
-        } finally{
+            logger.info("{}", () -> format("Handling exception: " + causeMessage));
+            logger.catching(Level.DEBUG, cause);
+        } finally {
             super.exceptionCaught(ctx, cause);
             ctx.flush();
             ctx.close();
@@ -99,9 +94,7 @@ private boolean needAck(Message message) {
     }
 
     private void ack(ChannelHandlerContext ctx, Message message) {
-        if (logger.isTraceEnabled()){
-            logger.trace(format("Acking message number " + message.getSequence()));
-        }
+        logger.trace("{}", () -> format("Acking message number " + message.getSequence()));
         writeAck(ctx, message.getBatch().getProtocol(), message.getSequence());
     }
 

src/main/java/org/logstash/beats/BeatsParser.java

@@ -18,7 +18,8 @@
 
 
 public class BeatsParser extends ByteToMessageDecoder {
-    private final static Logger logger = LogManager.getLogger(BeatsParser.class);
+
+    private static final Logger logger = LogManager.getLogger();
 
     private Batch batch;
 
@@ -195,9 +196,7 @@ protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) t
                 logger.trace("Running: READ_JSON");
                 ((V2Batch)batch).addMessage(sequence, in, requiredBytes);
                 if(batch.isComplete()) {
-                    if(logger.isTraceEnabled()) {
-                        logger.trace("Sending batch size: " + this.batch.size() + ", windowSize: " + batch.getBatchSize() + " , seq: " + sequence);
-                    }
+                    logger.trace("Sending batch size: {}, windowSize: {}, seq: {}", () -> batch.size(), () -> batch.getBatchSize() , () -> sequence);
                     out.add(batch);
                     batchComplete();
                 }
@@ -217,9 +216,7 @@ private void transition(States next) {
     }
 
     private void transition(States nextState, int requiredBytes) {
-        if(logger.isTraceEnabled()) {
-            logger.trace("Transition, from: " + currentState + ", to: " + nextState + ", requiring " + requiredBytes + " bytes");
-        }
+        logger.trace("{}", () -> "Transition, from: " + currentState + ", to: " + nextState + ", requiring " + requiredBytes + " bytes");
         this.currentState = nextState;
         this.requiredBytes = requiredBytes;
     }

src/main/java/org/logstash/beats/ConnectionHandler.java

@@ -16,16 +16,15 @@
  * Manages the connection state to the beats client.
  */
 public class ConnectionHandler extends ChannelDuplexHandler {
-    private final static Logger logger = LogManager.getLogger(ConnectionHandler.class);
+
+    private final static Logger logger = LogManager.getLogger();
 
     public static AttributeKey<AtomicBoolean> CHANNEL_SEND_KEEP_ALIVE = AttributeKey.valueOf("channel-send-keep-alive");
 
     @Override
     public void channelActive(final ChannelHandlerContext ctx) throws Exception {
         ctx.channel().attr(CHANNEL_SEND_KEEP_ALIVE).set(new AtomicBoolean(false));
-        if (logger.isTraceEnabled()) {
-            logger.trace("{}: channel activated", ctx.channel().id().asShortText());
-        }
+        logger.trace("{}: channel activated", () -> ctx.channel().id().asShortText());
         super.channelActive(ctx);
     }
 
@@ -37,9 +36,9 @@ public void channelActive(final ChannelHandlerContext ctx) throws Exception {
     @Override
     public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
         ctx.channel().attr(CHANNEL_SEND_KEEP_ALIVE).get().set(true);
-        if (logger.isDebugEnabled()) {
-            logger.debug("{}: batches pending: {}", ctx.channel().id().asShortText(),ctx.channel().attr(CHANNEL_SEND_KEEP_ALIVE).get().get());
-        }
+        logger.debug("{}: batches pending: {}",
+                     () -> ctx.channel().id().asShortText(),
+                     () -> ctx.channel().attr(CHANNEL_SEND_KEEP_ALIVE).get().get());
         super.channelRead(ctx, msg);
     }
 
@@ -80,7 +79,8 @@ public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exc
                     }
                 }
             } else if (e.state() == IdleState.ALL_IDLE) {
-                logger.debug("{}: reader and writer are idle, closing remote connection", ctx.channel().id().asShortText());
+                logger.debug("{}: reader and writer are idle, closing remote connection",
+                             () -> ctx.channel().id().asShortText());
                 ctx.flush();
                 ChannelFuture f = ctx.close();
                 if (logger.isTraceEnabled()) {

src/main/java/org/logstash/beats/MessageListener.java

@@ -12,7 +12,8 @@
  */
 // This need to be implemented in Ruby
 public class MessageListener implements IMessageListener {
-    private final static Logger logger = LogManager.getLogger(MessageListener.class);
+
+    private static final Logger logger = LogManager.getLogger();
 
 
     /**

src/main/java/org/logstash/beats/Runner.java

@@ -8,9 +8,7 @@
 public class Runner {
     private static final int DEFAULT_PORT = 5044;
 
-    private final static Logger logger = LogManager.getLogger(Runner.class);
-
-
+    private static final Logger logger = LogManager.getLogger();
 
     static public void main(String[] args) throws Exception {
         logger.info("Starting Beats Bulk");

src/main/java/org/logstash/beats/Server.java

@@ -18,7 +18,8 @@
 import java.security.cert.CertificateException;
 
 public class Server {
-    private final static Logger logger = LogManager.getLogger(Server.class);
+
+    private static final Logger logger = LogManager.getLogger();
 
     private final int port;
     private final String host;
@@ -52,7 +53,7 @@ public Server listen() throws InterruptedException {
         }
         workGroup = new NioEventLoopGroup();
         try {
-            logger.info("Starting server on port: {}", this.port);
+            logger.info("Starting server on port: {}", port);
 
             beatsInitializer = new BeatsInitializer(isSslEnable(), messageListener, clientInactivityTimeoutSeconds, beatsHeandlerThreadCount);
 

src/main/java/org/logstash/netty/SslSimpleBuilder.java

@@ -30,7 +30,7 @@ public static enum SslClientVerifyMode {
         VERIFY_PEER,
         FORCE_PEER,
     }
-    private final static Logger logger = LogManager.getLogger(SslSimpleBuilder.class);
+    private static final Logger logger = LogManager.getLogger();
 
 
     private File sslKeyFile;
@@ -77,7 +77,7 @@ public SslSimpleBuilder setCipherSuites(String[] ciphersSuite) throws IllegalArg
             if(!OpenSsl.isCipherSuiteAvailable(cipher)) {
                 throw new IllegalArgumentException("Cipher `" + cipher + "` is not available");
             } else {
-                logger.debug("Cipher is supported: " + cipher);
+                logger.debug("Cipher is supported: {}", cipher);
             }
         }
 
@@ -111,25 +111,21 @@ public File getSslCertificateFile() {
     public SslHandler build(ByteBufAllocator bufferAllocator) throws IOException, NoSuchAlgorithmException, CertificateException {
         SslContextBuilder builder = SslContextBuilder.forServer(sslCertificateFile, sslKeyFile, passPhrase);
 
-        if(logger.isDebugEnabled())
-            logger.debug("Available ciphers:" + Arrays.toString(OpenSsl.availableOpenSslCipherSuites().toArray()));
-            logger.debug("Ciphers:  " + Arrays.toString(ciphers));
+        logger.debug("Available ciphers: {}", () ->Arrays.toString(OpenSsl.availableOpenSslCipherSuites().toArray()));
+        logger.debug("Ciphers:  {}", () -> Arrays.toString(ciphers));
 
 
         builder.ciphers(Arrays.asList(ciphers));
 
-        if(requireClientAuth()) {
-            if (logger.isDebugEnabled())
-                logger.debug("Certificate Authorities: " + Arrays.toString(certificateAuthorities));
-
+        if (requireClientAuth()) {
+            logger.debug("Certificate Authorities: {}", () -> Arrays.toString(certificateAuthorities));
             builder.trustManager(loadCertificateCollection(certificateAuthorities));
         }
 
         SslContext context = builder.build();
         SslHandler sslHandler = context.newHandler(bufferAllocator);
 
-        if(logger.isDebugEnabled())
-            logger.debug("TLS: " + Arrays.toString(protocols));
+        logger.debug("TLS: {}", () -> Arrays.toString(protocols));
 
         SSLEngine engine = sslHandler.engine();
         engine.setEnabledProtocols(protocols);
@@ -162,7 +158,7 @@ private X509Certificate[] loadCertificateCollection(String[] certificates) throw
         for(int i = 0; i < certificates.length; i++) {
             String certificate = certificates[i];
 
-            logger.debug("Loading certificates from file " + certificate);
+            logger.debug("Loading certificates from file {}", ()-> certificate);
 
             try(InputStream in = new FileInputStream(certificate)) {
                 List<X509Certificate> certificatesChains = (List<X509Certificate>) certificateFactory.generateCertificates(in);