Polish Reactor Netty TCP client support

spring-messaging/src/main/java/org/springframework/messaging/simp/stomp/ReactorNettyTcpStompClient.java

@@ -29,11 +29,10 @@ import org.springframework.messaging.tcp.reactor.ReactorNettyTcpClient;
 import org.springframework.util.concurrent.ListenableFuture;
 
 /**
- * A STOMP over TCP client that uses
+ * A STOMP over TCP client that uses {@link ReactorNettyTcpClient}.
- * {@link ReactorNettyTcpClient}.
  *
  * @author Rossen Stoyanchev
- * @since 4.2
+ * @since 5.0
  */
 public class ReactorNettyTcpStompClient extends StompClientSupport {
 
@@ -99,25 +98,21 @@ public class ReactorNettyTcpStompClient extends StompClientSupport {
 	 * Create a new {@link ReactorNettyTcpClient} with Stomp specific configuration for
 	 * encoding, decoding and hand-off.
 	 *
-	 * @param relayHost target host
+	 * @param host target host
-	 * @param relayPort target port
+	 * @param port target port
 	 * @param decoder {@link StompDecoder} to use
 	 * @return a new {@link TcpOperations}
 	 */
-	protected static TcpOperations<byte[]> create(String relayHost,
+	protected static TcpOperations<byte[]> create(String host, int port, StompDecoder decoder) {
-			int relayPort,
+		return new ReactorNettyTcpClient<>(host, port,
-			StompDecoder decoder) {
+				new ReactorNettyTcpClient.MessageHandlerConfiguration<>(
-		return new ReactorNettyTcpClient<>(relayHost,
+						new DecodingFunction(decoder),
-				relayPort,
-				new ReactorNettyTcpClient.MessageHandlerConfiguration<>(new DecodingFunction(
-						decoder),
 						new EncodingConsumer(new StompEncoder()),
 						128,
 						Schedulers.newParallel("StompClient")));
 	}
 
-	private static final class EncodingConsumer
+	private static final class EncodingConsumer implements BiConsumer<ByteBuf, Message<byte[]>> {
-			implements BiConsumer<ByteBuf, Message<byte[]>> {
 
 		private final StompEncoder encoder;
 
@@ -127,12 +122,11 @@ public class ReactorNettyTcpStompClient extends StompClientSupport {
 
 		@Override
 		public void accept(ByteBuf byteBuf, Message<byte[]> message) {
-			byteBuf.writeBytes(encoder.encode(message));
+			byteBuf.writeBytes(this.encoder.encode(message));
 		}
 	}
 
-	private static final class DecodingFunction
+	private static final class DecodingFunction implements Function<ByteBuf, List<Message<byte[]>>> {
-			implements Function<ByteBuf, List<Message<byte[]>>> {
 
 		private final StompDecoder decoder;
 

spring-messaging/src/main/java/org/springframework/messaging/tcp/reactor/AbstractMonoToListenableFutureAdapter.java

@@ -17,7 +17,6 @@
 package org.springframework.messaging.tcp.reactor;
 
 import java.time.Duration;
-import java.util.Objects;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
@@ -33,51 +32,53 @@ import org.springframework.util.concurrent.ListenableFutureCallbackRegistry;
 import org.springframework.util.concurrent.SuccessCallback;
 
 /**
- * Adapts a reactor {@link Mono} to {@link ListenableFuture} optionally converting
+ * Adapts {@link Mono} to {@link ListenableFuture} optionally converting the
- * the result Object type {@code <S>} to the expected target type {@code <T>}.
+ * result Object type {@code <S>} to the expected target type {@code <T>}.
  *
  * @author Rossen Stoyanchev
- * @since 4.0
+ * @since 5.0
  * @param <S> the type of object expected from the {@link Mono}
  * @param <T> the type of object expected from the {@link ListenableFuture}
  */
-abstract class AbstractMonoToListenableFutureAdapter<S, T>
+abstract class AbstractMonoToListenableFutureAdapter<S, T> implements ListenableFuture<T> {
-		implements ListenableFuture<T> {
 
-	private final MonoProcessor<S> promise;
+	private final MonoProcessor<S> monoProcessor;
 
 	private final ListenableFutureCallbackRegistry<T> registry = new ListenableFutureCallbackRegistry<>();
 
-	protected AbstractMonoToListenableFutureAdapter(Mono<S> promise) {
+
-		Assert.notNull(promise, "Mono must not be null");
+	protected AbstractMonoToListenableFutureAdapter(Mono<S> mono) {
-		this.promise = promise.doOnSuccess(result -> {
+		Assert.notNull(mono, "'mono' must not be null");
-				T adapted;
+		this.monoProcessor = mono
-				try {
+				.doOnSuccess(result -> {
-					adapted = adapt(result);
+					T adapted;
-				}
+					try {
-				catch (Throwable ex) {
+						adapted = adapt(result);
-					registry.failure(ex);
+					}
-					return;
+					catch (Throwable ex) {
-				}
+						registry.failure(ex);
-				registry.success(adapted);
+						return;
-		})
+					}
-		                      .doOnError(registry::failure)
+					registry.success(adapted);
-		                      .subscribe();
+				})
+				.doOnError(this.registry::failure)
+				.subscribe();
 	}
 
 
 	@Override
 	public T get() throws InterruptedException {
-		S result = this.promise.block();
+		S result = this.monoProcessor.block();
 		return adapt(result);
 	}
 
 	@Override
-	public T get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException {
+	public T get(long timeout, TimeUnit unit)
-		Objects.requireNonNull(unit, "unit");
+			throws InterruptedException, ExecutionException, TimeoutException {
-		S result = this.promise.block(Duration.ofMillis(TimeUnit.MILLISECONDS.convert(
+
-				timeout,
+		Assert.notNull(unit);
-				unit)));
+		Duration duration = Duration.ofMillis(TimeUnit.MILLISECONDS.convert(timeout, unit));
+		S result = this.monoProcessor.block(duration);
 		return adapt(result);
 	}
 
@@ -86,18 +87,18 @@ abstract class AbstractMonoToListenableFutureAdapter<S, T>
 		if (isCancelled()) {
 			return false;
 		}
-		this.promise.cancel();
+		this.monoProcessor.cancel();
 		return true;
 	}
 
 	@Override
 	public boolean isCancelled() {
-		return this.promise.isCancelled();
+		return this.monoProcessor.isCancelled();
 	}
 
 	@Override
 	public boolean isDone() {
-		return this.promise.isTerminated();
+		return this.monoProcessor.isTerminated();
 	}
 
 	@Override
@@ -111,7 +112,6 @@ abstract class AbstractMonoToListenableFutureAdapter<S, T>
 		this.registry.addFailureCallback(failureCallback);
 	}
 
-
 	protected abstract T adapt(S result);
 
 }

spring-messaging/src/main/java/org/springframework/messaging/tcp/reactor/MonoToListenableFutureAdapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,15 +19,14 @@ package org.springframework.messaging.tcp.reactor;
 import reactor.core.publisher.Mono;
 
 /**
- * A Mono-to-ListenableFutureAdapter where the source and the target from
+ * A Mono-to-ListenableFuture adapter where the source and the target from
  * the Promise and the ListenableFuture respectively are of the same type.
  *
  * @author Rossen Stoyanchev
  * @author Stephane Maldini
- * @since 4.0
+ * @since 5.0
  */
-class MonoToListenableFutureAdapter<T> extends
+class MonoToListenableFutureAdapter<T> extends AbstractMonoToListenableFutureAdapter<T, T> {
-                                       AbstractMonoToListenableFutureAdapter<T, T> {
 
 
 	public MonoToListenableFutureAdapter(Mono<T> mono) {

spring-messaging/src/main/java/org/springframework/messaging/tcp/reactor/ReactorNettyTcpClient.java

@@ -17,7 +17,6 @@
 package org.springframework.messaging.tcp.reactor;
 
 import java.util.Collection;
-import java.util.Objects;
 import java.util.function.BiConsumer;
 import java.util.function.BiFunction;
 import java.util.function.Consumer;
@@ -58,16 +57,19 @@ import org.springframework.util.concurrent.ListenableFuture;
  *
  * @author Rossen Stoyanchev
  * @author Stephane Maldini
- * @since 4.2
+ * @since 5.0
  */
 public class ReactorNettyTcpClient<P> implements TcpOperations<P> {
 
-	private final TcpClient                      tcpClient;
+	private final TcpClient tcpClient;
 
 	private final MessageHandlerConfiguration<P> configuration;
-	private final ChannelGroup                   group;
+
+	private final ChannelGroup group;
+
 	private volatile boolean stopping;
 
+
 	/**
 	 * A constructor that creates a {@link TcpClient TcpClient} factory relying on
 	 * Reactor Netty TCP threads. The number of Netty threads can be tweaked with
@@ -80,120 +82,116 @@ public class ReactorNettyTcpClient<P> implements TcpOperations<P> {
 	 * @param port the port to connect to
 	 * @param configuration the client configuration
 	 */
-	public ReactorNettyTcpClient(String host,
+	public ReactorNettyTcpClient(String host, int port, MessageHandlerConfiguration<P> configuration) {
-			int port,
+		this(opts -> opts.connect(host, port), configuration);
-			MessageHandlerConfiguration<P> configuration) {
-		this.configuration = Objects.requireNonNull(configuration, "configuration");
-		this.group = new DefaultChannelGroup(ImmediateEventExecutor.INSTANCE);
-		this.tcpClient = TcpClient.create(options -> options.connect(host, port)
-		                                                    .channelGroup(group));
 	}
 
 	/**
-	 * A constructor with a configurator {@link Consumer} that will receive default {@link
+	 * A constructor with a configurator {@link Consumer} that will receive
-	 * ClientOptions} from {@link TcpClient}. This might be used to add SSL or specific
+	 * default {@link ClientOptions} from {@link TcpClient}. This might be used
-	 * network parameters to the generated client configuration.
+	 * to add SSL or specific network parameters to the generated client
+	 * configuration.
 	 *
-	 * @param tcpOptions the {@link Consumer} of {@link ClientOptions} shared to use by
+	 * @param tcpOptions callback for configuring shared {@link ClientOptions}
-	 * connected handlers.
 	 * @param configuration the client configuration
 	 */
 	public ReactorNettyTcpClient(Consumer<? super ClientOptions> tcpOptions,
 			MessageHandlerConfiguration<P> configuration) {
-		this.configuration = Objects.requireNonNull(configuration, "configuration");
+
+		Assert.notNull(configuration, "'configuration' is required");
 		this.group = new DefaultChannelGroup(ImmediateEventExecutor.INSTANCE);
-		this.tcpClient =
+		this.tcpClient = TcpClient.create(opts -> tcpOptions.accept(opts.channelGroup(group)));
-				TcpClient.create(opts -> tcpOptions.accept(opts.channelGroup(group)));
+		this.configuration = configuration;
 	}
 
+
 	@Override
-	public ListenableFuture<Void> connect(final TcpConnectionHandler<P> connectionHandler) {
+	public ListenableFuture<Void> connect(final TcpConnectionHandler<P> handler) {
-		Assert.notNull(connectionHandler, "TcpConnectionHandler must not be null");
+		Assert.notNull(handler, "'handler' is required");
-		if (stopping) {
+
+		if (this.stopping) {
 			IllegalStateException ex = new IllegalStateException("Shutting down.");
-			connectionHandler.afterConnectFailure(ex);
+			handler.afterConnectFailure(ex);
 			return new MonoToListenableFutureAdapter<>(Mono.<Void>error(ex));
 		}
 
-		MessageHandler<P> handler =
+		Mono<Void> connectMono = this.tcpClient
-				new MessageHandler<>(connectionHandler, configuration);
+				.newHandler(new MessageHandler<>(handler, this.configuration))
+				.doOnError(handler::afterConnectFailure)
+				.then();
 
-		Mono<Void> promise = tcpClient.newHandler(handler)
+		return new MonoToListenableFutureAdapter<>(connectMono);
-		                              .doOnError(connectionHandler::afterConnectFailure)
-		                              .then();
-
-		return new MonoToListenableFutureAdapter<>(promise);
 	}
 
 	@Override
-	public ListenableFuture<Void> connect(TcpConnectionHandler<P> connectionHandler,
+	public ListenableFuture<Void> connect(TcpConnectionHandler<P> handler, ReconnectStrategy strategy) {
-			ReconnectStrategy strategy) {
+		Assert.notNull(handler, "'handler' is required");
-		Assert.notNull(connectionHandler, "TcpConnectionHandler must not be null");
+		Assert.notNull(strategy, "'reconnectStrategy' is required");
-		Assert.notNull(strategy, "ReconnectStrategy must not be null");
 
-		if (stopping) {
+		if (this.stopping) {
 			IllegalStateException ex = new IllegalStateException("Shutting down.");
-			connectionHandler.afterConnectFailure(ex);
+			handler.afterConnectFailure(ex);
 			return new MonoToListenableFutureAdapter<>(Mono.<Void>error(ex));
 		}
 
-		MessageHandler<P> handler =
+		MonoProcessor<Void> connectMono = MonoProcessor.create();
-				new MessageHandler<>(connectionHandler, configuration);
 
-		MonoProcessor<Void> promise = MonoProcessor.create();
+		this.tcpClient.newHandler(new MessageHandler<>(handler, this.configuration))
+				.doOnNext(item -> {
+					if (!connectMono.isTerminated()) {
+						connectMono.onComplete();
+					}
+				})
+				.doOnError(ex -> {
+					if (!connectMono.isTerminated()) {
+						connectMono.onError(ex);
+					}
+				})
+				.then(NettyContext::onClose)
+				.retryWhen(new Reconnector<>(strategy))
+				.repeatWhen(new Reconnector<>(strategy))
+				.subscribe();
 
-		tcpClient.newHandler(handler)
+		return new MonoToListenableFutureAdapter<>(connectMono);
-		         .doOnNext(e -> {
-			         if (!promise.isTerminated()) {
-				         promise.onComplete();
-			         }
-		         })
-		         .doOnError(e -> {
-			         if (!promise.isTerminated()) {
-				         promise.onError(e);
-			         }
-		         })
-		         .then(NettyContext::onClose)
-		         .retryWhen(new Reconnector<>(strategy))
-		         .repeatWhen(new Reconnector<>(strategy))
-		         .subscribe();
-
-		return new MonoToListenableFutureAdapter<>(promise);
 	}
 
 	@Override
 	public ListenableFuture<Void> shutdown() {
-		if (stopping) {
+		if (this.stopping) {
 			return new MonoToListenableFutureAdapter<>(Mono.empty());
 		}
 
-		stopping = true;
+		this.stopping = true;
 
-		Mono<Void> closing = ChannelFutureMono.from(group.close());
+		Mono<Void> completion = ChannelFutureMono.from(this.group.close());
 
-		if (configuration.scheduler != null) {
+		if (this.configuration.scheduler != null) {
-			closing =
+			completion = completion.doAfterTerminate((x, e) -> configuration.scheduler.shutdown());
-					closing.doAfterTerminate((x, e) -> configuration.scheduler.shutdown());
 		}
 
-		return new MonoToListenableFutureAdapter<>(closing);
+		return new MonoToListenableFutureAdapter<>(completion);
 	}
 
+
 	/**
 	 * A configuration holder
 	 */
 	public static final class MessageHandlerConfiguration<P> {
 
 		private final Function<? super ByteBuf, ? extends Collection<Message<P>>> decoder;
-		private final BiConsumer<? super ByteBuf, ? super Message<P>>             encoder;
-		private final int                                                         backlog;
-		private final Scheduler
-		                                                                          scheduler;
 
-		public MessageHandlerConfiguration(Function<? super ByteBuf, ? extends Collection<Message<P>>> decoder,
+		private final BiConsumer<? super ByteBuf, ? super Message<P>> encoder;
+
+		private final int backlog;
+
+		private final Scheduler scheduler;
+
+
+		public MessageHandlerConfiguration(
+				Function<? super ByteBuf, ? extends Collection<Message<P>>> decoder,
 				BiConsumer<? super ByteBuf, ? super Message<P>> encoder,
-				int backlog,
+				int backlog, Scheduler scheduler) {
-				Scheduler scheduler) {
+
 			this.decoder = decoder;
 			this.encoder = encoder;
 			this.backlog = backlog > 0 ? backlog : QueueSupplier.SMALL_BUFFER_SIZE;
@@ -201,34 +199,30 @@ public class ReactorNettyTcpClient<P> implements TcpOperations<P> {
 		}
 	}
 
-	private static final class MessageHandler<P> implements BiFunction<NettyInbound, NettyOutbound, Publisher<Void>> {
+	private static final class MessageHandler<P>
+			implements BiFunction<NettyInbound, NettyOutbound, Publisher<Void>> {
 
 		private final TcpConnectionHandler<P> connectionHandler;
 
 		private final MessageHandlerConfiguration<P> configuration;
 
-		MessageHandler(TcpConnectionHandler<P> connectionHandler,
+
-				MessageHandlerConfiguration<P> configuration) {
+		MessageHandler(TcpConnectionHandler<P> handler, MessageHandlerConfiguration<P> config) {
-			this.connectionHandler = connectionHandler;
+			this.connectionHandler = handler;
-			this.configuration = configuration;
+			this.configuration = config;
 		}
 
 		@Override
 		public Publisher<Void> apply(NettyInbound in, NettyOutbound out) {
-			Flux<Collection<Message<P>>> inbound = in.receive()
+			Flux<Collection<Message<P>>> inbound = in.receive().map(configuration.decoder);
-			                                         .map(configuration.decoder);
 
-			DirectProcessor<Void> promise = DirectProcessor.create();
+			DirectProcessor<Void> closeProcessor = DirectProcessor.create();
-			TcpConnection<P> tcpConnection = new ReactorNettyTcpConnection<>(in,
+			TcpConnection<P> tcpConnection =
-					out,
+					new ReactorNettyTcpConnection<>(in, out, configuration.encoder, closeProcessor);
-					configuration.encoder,
-					promise);
 
 			if (configuration.scheduler != null) {
-				configuration.scheduler.schedule(() -> connectionHandler.afterConnected(
+				configuration.scheduler.schedule(() -> connectionHandler.afterConnected(tcpConnection));
-						tcpConnection));
+				inbound = inbound.publishOn(configuration.scheduler, configuration.backlog);
-				inbound =
-						inbound.publishOn(configuration.scheduler, configuration.backlog);
 			}
 			else {
 				connectionHandler.afterConnected(tcpConnection);
@@ -239,15 +233,16 @@ public class ReactorNettyTcpClient<P> implements TcpOperations<P> {
 					       connectionHandler::handleFailure,
 					       connectionHandler::afterConnectionClosed);
 
-			return promise;
+			return closeProcessor;
 		}
 
 	}
 
-	static final class Reconnector<T> implements Function<Flux<T>, Publisher<?>> {
+	private static final class Reconnector<T> implements Function<Flux<T>, Publisher<?>> {
 
 		private final ReconnectStrategy strategy;
 
+
 		Reconnector(ReconnectStrategy strategy) {
 			this.strategy = strategy;
 		}
@@ -255,9 +250,7 @@ public class ReactorNettyTcpClient<P> implements TcpOperations<P> {
 		@Override
 		public Publisher<?> apply(Flux<T> flux) {
 			return flux.scan(1, (p, e) -> p++)
-			           .doOnCancel(() -> new Exception().printStackTrace())
+					.flatMap(attempt -> Mono.delayMillis(strategy.getTimeToNextAttempt(attempt)));
-			           .flatMap(attempt -> Mono.delayMillis(strategy.getTimeToNextAttempt(
-					           attempt)));
 		}
 	}
 

spring-messaging/src/main/java/org/springframework/messaging/tcp/reactor/ReactorNettyTcpConnection.java

@@ -35,47 +35,52 @@ import org.springframework.util.concurrent.ListenableFuture;
  * @param <P> the payload type of messages read or written to the TCP stream.
  *
  * @author Rossen Stoyanchev
- * @since 4.2
+ * @since 5.0
  */
 public class ReactorNettyTcpConnection<P> implements TcpConnection<P> {
 
-	private final NettyInbound                                    in;
+	private final NettyInbound inbound;
-	private final NettyOutbound                                   out;
+
-	private final DirectProcessor<Void>                           close;
+	private final NettyOutbound outbound;
+
+	private final DirectProcessor<Void> closeProcessor;
+
 	private final BiConsumer<? super ByteBuf, ? super Message<P>> encoder;
 
-	public ReactorNettyTcpConnection(NettyInbound in,
+
-			NettyOutbound out,
+	public ReactorNettyTcpConnection(NettyInbound inbound, NettyOutbound outbound,
 			BiConsumer<? super ByteBuf, ? super Message<P>> encoder,
-			DirectProcessor<Void> close) {
+			DirectProcessor<Void> closeProcessor) {
-		this.out = out;
+
-		this.in = in;
+		this.inbound = inbound;
+		this.outbound = outbound;
 		this.encoder = encoder;
-		this.close = close;
+		this.closeProcessor = closeProcessor;
 	}
 
+
 	@Override
 	public ListenableFuture<Void> send(Message<P> message) {
-		ByteBuf byteBuf = in.channel().alloc().buffer();
+		ByteBuf byteBuf = this.inbound.channel().alloc().buffer();
-		encoder.accept(byteBuf, message);
+		this.encoder.accept(byteBuf, message);
-		return new MonoToListenableFutureAdapter<>(out.send(Mono.just(byteBuf)));
+		return new MonoToListenableFutureAdapter<>(this.outbound.send(Mono.just(byteBuf)));
 	}
 
 	@Override
 	@SuppressWarnings("deprecation")
 	public void onReadInactivity(Runnable runnable, long inactivityDuration) {
-		in.onReadIdle(inactivityDuration, runnable);
+		this.inbound.onReadIdle(inactivityDuration, runnable);
 	}
 
 	@Override
 	@SuppressWarnings("deprecation")
 	public void onWriteInactivity(Runnable runnable, long inactivityDuration) {
-		out.onWriteIdle(inactivityDuration, runnable);
+		this.outbound.onWriteIdle(inactivityDuration, runnable);
 	}
 
 	@Override
 	public void close() {
-		close.onComplete();
+		this.closeProcessor.onComplete();
 	}
 
 }

spring-messaging/src/test/java/org/springframework/messaging/simp/stomp/StompDecoderTests.java

@@ -24,10 +24,10 @@ import org.junit.Test;
 
 import org.springframework.messaging.Message;
 import org.springframework.messaging.simp.SimpMessageType;
-import org.springframework.messaging.support.MessageBuilder;
 import org.springframework.util.InvalidMimeTypeException;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 
 /**
  * Test fixture for {@link StompDecoder}.
@@ -39,6 +39,7 @@ public class StompDecoderTests {
 
 	private final StompDecoder decoder = new StompDecoder();
 
+
 	@Test
 	public void decodeFrameWithCrLfEols() {
 		Message<byte[]> frame = decode("DISCONNECT\r\n\r\n\0");

spring-messaging/src/test/java/org/springframework/messaging/simp/stomp/StompEncoderTests.java

@@ -34,10 +34,10 @@ public class StompEncoderTests {
 
 	private final StompEncoder encoder = new StompEncoder();
 
+
 	@Test
 	public void encodeFrameWithNoHeadersAndNoBody() {
 		StompHeaderAccessor headers = StompHeaderAccessor.create(StompCommand.DISCONNECT);
-
 		Message<byte[]> frame = MessageBuilder.createMessage(new byte[0], headers.getMessageHeaders());
 
 		assertEquals("DISCONNECT\n\n\0", new String(encoder.encode(frame)));
@@ -48,20 +48,18 @@ public class StompEncoderTests {
 		StompHeaderAccessor headers = StompHeaderAccessor.create(StompCommand.CONNECT);
 		headers.setAcceptVersion("1.2");
 		headers.setHost("github.org");
-
 		Message<byte[]> frame = MessageBuilder.createMessage(new byte[0], headers.getMessageHeaders());
-
 		String frameString = new String(encoder.encode(frame));
 
-		assertTrue("CONNECT\naccept-version:1.2\nhost:github.org\n\n\0".equals(frameString) || "CONNECT\nhost:github.org\naccept-version:1.2\n\n\0".equals(
+		assertTrue(
-				frameString));
+				"CONNECT\naccept-version:1.2\nhost:github.org\n\n\0".equals(frameString) ||
+				"CONNECT\nhost:github.org\naccept-version:1.2\n\n\0".equals(frameString));
 	}
 
 	@Test
 	public void encodeFrameWithHeadersThatShouldBeEscaped() {
 		StompHeaderAccessor headers = StompHeaderAccessor.create(StompCommand.DISCONNECT);
 		headers.addNativeHeader("a:\r\n\\b",  "alpha:bravo\r\n\\");
-
 		Message<byte[]> frame = MessageBuilder.createMessage(new byte[0], headers.getMessageHeaders());
 
 		assertEquals("DISCONNECT\na\\c\\r\\n\\\\b:alpha\\cbravo\\r\\n\\\\\n\n\0",
@@ -72,8 +70,8 @@ public class StompEncoderTests {
 	public void encodeFrameWithHeadersBody() {
 		StompHeaderAccessor headers = StompHeaderAccessor.create(StompCommand.SEND);
 		headers.addNativeHeader("a", "alpha");
-
+		Message<byte[]> frame = MessageBuilder.createMessage(
-		Message<byte[]> frame = MessageBuilder.createMessage("Message body".getBytes(), headers.getMessageHeaders());
+				"Message body".getBytes(), headers.getMessageHeaders());
 
 		assertEquals("SEND\na:alpha\ncontent-length:12\n\nMessage body\0",
 				new String(encoder.encode(frame)));
@@ -83,8 +81,8 @@ public class StompEncoderTests {
 	public void encodeFrameWithContentLengthPresent() {
 		StompHeaderAccessor headers = StompHeaderAccessor.create(StompCommand.SEND);
 		headers.setContentLength(12);
-
+		Message<byte[]> frame = MessageBuilder.createMessage(
-		Message<byte[]> frame = MessageBuilder.createMessage("Message body".getBytes(), headers.getMessageHeaders());
+				"Message body".getBytes(), headers.getMessageHeaders());
 
 		assertEquals("SEND\ncontent-length:12\n\nMessage body\0",
 				new String(encoder.encode(frame)));