Use configured gson instance for toString

This is important when users have registered custom type adapters

Fixes eclipse-lsp4j#768

org.eclipse.lsp4j.jsonrpc.debug/src/main/java/org/eclipse/lsp4j/jsonrpc/debug/DebugLauncher.java

@@ -210,7 +210,7 @@ protected MessageJsonHandler createJsonHandler() {
 		@Override
 		protected RemoteEndpoint createRemoteEndpoint(MessageJsonHandler jsonHandler) {
 			MessageConsumer outgoingMessageStream = new StreamMessageConsumer(output, jsonHandler);
-			outgoingMessageStream = wrapMessageConsumer(outgoingMessageStream);
+			outgoingMessageStream = wrapMessageConsumer(outgoingMessageStream, jsonHandler);
 			Endpoint localEndpoint = ServiceEndpoints.toEndpoint(localServices);
 			RemoteEndpoint remoteEndpoint;
 			if (exceptionHandler == null)

org.eclipse.lsp4j.jsonrpc/src/main/java/org/eclipse/lsp4j/jsonrpc/Launcher.java

@@ -235,7 +235,7 @@ public static class Builder<T> {
 		protected boolean validateMessages;
 		protected Consumer<GsonBuilder> configureGson;
 		protected ClassLoader classLoader;
-		protected MessageTracer messageTracer;
+		protected PrintWriter messageTracer;
 
 		public Builder<T> setLocalService(Object localService) {
 			this.localServices = Collections.singletonList(localService);
@@ -294,7 +294,7 @@ public Builder<T> validateMessages(boolean validate) {
 
 		public Builder<T> traceMessages(PrintWriter tracer) {
 			if (tracer != null) {
-				this.messageTracer = new MessageTracer(tracer);
+				this.messageTracer = tracer;
 			}
 			return this;
 		}
@@ -322,7 +322,7 @@ public Launcher<T> create() {
 
 			// Create the message processor
 			StreamMessageProducer reader = new StreamMessageProducer(input, jsonHandler, remoteEndpoint);
-			MessageConsumer messageConsumer = wrapMessageConsumer(remoteEndpoint);
+			MessageConsumer messageConsumer = wrapMessageConsumer(remoteEndpoint, jsonHandler);
 			ConcurrentMessageProcessor msgProcessor = createMessageProcessor(reader, messageConsumer, remoteProxy);
 			ExecutorService execService = executorService != null ? executorService : Executors.newCachedThreadPool();
 			return createLauncher(execService, remoteProxy, remoteEndpoint, msgProcessor);
@@ -344,7 +344,7 @@ protected MessageJsonHandler createJsonHandler() {
 		 */
 		protected RemoteEndpoint createRemoteEndpoint(MessageJsonHandler jsonHandler) {
 			MessageConsumer outgoingMessageStream = new StreamMessageConsumer(output, jsonHandler);
-			outgoingMessageStream = wrapMessageConsumer(outgoingMessageStream);
+			outgoingMessageStream = wrapMessageConsumer(outgoingMessageStream, jsonHandler);
 			Endpoint localEndpoint = ServiceEndpoints.toEndpoint(localServices);
 			RemoteEndpoint remoteEndpoint;
 			if (exceptionHandler == null)
@@ -380,10 +380,10 @@ protected Launcher<T> createLauncher(ExecutorService execService, T remoteProxy,
 			return new StandardLauncher<T>(execService, remoteProxy, remoteEndpoint, msgProcessor);
 		}
 
-		protected MessageConsumer wrapMessageConsumer(MessageConsumer consumer) {
+		protected MessageConsumer wrapMessageConsumer(MessageConsumer consumer, MessageJsonHandler jsonHandler) {
 			MessageConsumer result = consumer;
 			if (messageTracer != null) {
-				result = messageTracer.apply(consumer);
+				result = new MessageTracer(messageTracer, jsonHandler).apply(consumer);
 			}
 			if (validateMessages) {
 				result = new ReflectiveMessageValidator(result);

org.eclipse.lsp4j.jsonrpc/src/main/java/org/eclipse/lsp4j/jsonrpc/MessageTracer.java

@@ -19,23 +19,26 @@
 import java.util.Map;
 import java.util.Objects;
 import java.util.function.Function;
+import org.eclipse.lsp4j.jsonrpc.json.MessageJsonHandler;
 
 /**
  * Wraps a {@link MessageConsumer} with one that logs in a way that the LSP Inspector can parse. *
  * https://microsoft.github.io/language-server-protocol/inspector/
  */
 public class MessageTracer implements Function<MessageConsumer, MessageConsumer> {
 	private final PrintWriter printWriter;
+	private final MessageJsonHandler jsonHandler;
 	private final Map<String, RequestMetadata> sentRequests = new HashMap<>();
 	private final Map<String, RequestMetadata> receivedRequests = new HashMap<>();
 
-	MessageTracer(PrintWriter printWriter) {
+	MessageTracer(PrintWriter printWriter, MessageJsonHandler jsonHandler) {
 		this.printWriter = Objects.requireNonNull(printWriter);
+		this.jsonHandler = Objects.requireNonNull(jsonHandler);
 	}
 
 	@Override
 	public MessageConsumer apply(MessageConsumer messageConsumer) {
 		return new TracingMessageConsumer(
-				messageConsumer, sentRequests, receivedRequests, printWriter, Clock.systemDefaultZone());
+				messageConsumer, sentRequests, receivedRequests, printWriter, jsonHandler, Clock.systemDefaultZone());
 	}
 }

org.eclipse.lsp4j.jsonrpc/src/main/java/org/eclipse/lsp4j/jsonrpc/TracingMessageConsumer.java

@@ -40,6 +40,7 @@ public class TracingMessageConsumer implements MessageConsumer {
 	private final Map<String, RequestMetadata> sentRequests;
 	private final Map<String, RequestMetadata> receivedRequests;
 	private final PrintWriter printWriter;
+	private final MessageJsonHandler jsonHandler;
 	private final Clock clock;
 	private final DateTimeFormatter dateTimeFormatter;
 
@@ -55,8 +56,9 @@ public TracingMessageConsumer(
 			Map<String, RequestMetadata> sentRequests,
 			Map<String, RequestMetadata> receivedRequests,
 			PrintWriter printWriter,
+		  MessageJsonHandler jsonHandler,
 			Clock clock) {
-		this(messageConsumer, sentRequests, receivedRequests, printWriter, clock, null);
+		this(messageConsumer, sentRequests, receivedRequests, printWriter, jsonHandler, clock, null);
 	}
 
 	/**
@@ -72,12 +74,14 @@ public TracingMessageConsumer(
 			Map<String, RequestMetadata> sentRequests,
 			Map<String, RequestMetadata> receivedRequests,
 			PrintWriter printWriter,
+			MessageJsonHandler jsonHandler,
 			Clock clock,
 			Locale locale) {
 		this.messageConsumer = Objects.requireNonNull(messageConsumer);
 		this.sentRequests = Objects.requireNonNull(sentRequests);
 		this.receivedRequests = Objects.requireNonNull(receivedRequests);
 		this.printWriter = Objects.requireNonNull(printWriter);
+		this.jsonHandler = jsonHandler;
 		this.clock = Objects.requireNonNull(clock);
 		if (locale == null) {
 			this.dateTimeFormatter = DateTimeFormatter.ofPattern("KK:mm:ss a").withZone(clock.getZone());
@@ -122,7 +126,7 @@ private String consumeMessageSending(Message message, Instant now, String date)
 			RequestMetadata requestMetadata = new RequestMetadata(method, now);
 			sentRequests.put(id, requestMetadata);
 			Object params = requestMessage.getParams();
-			String paramsJson = MessageJsonHandler.toString(params);
+			String paramsJson = jsonHandler.toString(params);
 			String format = "[Trace - %s] Sending request '%s - (%s)'\nParams: %s\n\n\n";
 			return String.format(format, date, method, id, paramsJson);
 		} else if (message instanceof ResponseMessage) {
@@ -136,15 +140,15 @@ private String consumeMessageSending(Message message, Instant now, String date)
 			String method = requestMetadata.method;
 			long latencyMillis = now.toEpochMilli() - requestMetadata.start.toEpochMilli();
 			Object result = responseMessage.getResult();
-			String resultJson = MessageJsonHandler.toString(result);
+			String resultJson = jsonHandler.toString(result);
 			String format =
 					"[Trace - %s] Sending response '%s - (%s)'. Processing request took %sms\nResult: %s\n\n\n";
 			return String.format(format, date, method, id, latencyMillis, resultJson);
 		} else if (message instanceof NotificationMessage) {
 			NotificationMessage notificationMessage = (NotificationMessage) message;
 			String method = notificationMessage.getMethod();
 			Object params = notificationMessage.getParams();
-			String paramsJson = MessageJsonHandler.toString(params);
+			String paramsJson = jsonHandler.toString(params);
 			String format = "[Trace - %s] Sending notification '%s'\nParams: %s\n\n\n";
 			return String.format(format, date, method, paramsJson);
 		} else {
@@ -161,30 +165,30 @@ private String consumeMessageReceiving(Message message, Instant now, String date
 			RequestMetadata requestMetadata = new RequestMetadata(method, now);
 			receivedRequests.put(id, requestMetadata);
 			Object params = requestMessage.getParams();
-			String paramsJson = MessageJsonHandler.toString(params);
+			String paramsJson = jsonHandler.toString(params);
 			String format = "[Trace - %s] Received request '%s - (%s)'\nParams: %s\n\n\n";
 			return String.format(format, date, method, id, paramsJson);
 		} else if (message instanceof ResponseMessage) {
 			ResponseMessage responseMessage = (ResponseMessage) message;
 			String id = responseMessage.getId();
 			RequestMetadata requestMetadata = sentRequests.remove(id);
 			if (requestMetadata == null) {
-				LOG.log(WARNING, String.format("Unmatched response message: %s", message));
+				LOG.log(WARNING, String.format("Unmatched response message: %s", jsonHandler.toString(message)));
 				return null;
 			}
 			String method = requestMetadata.method;
 			long latencyMillis = now.toEpochMilli() - requestMetadata.start.toEpochMilli();
 			Object result = responseMessage.getResult();
-			String resultJson = MessageJsonHandler.toString(result);
+			String resultJson = jsonHandler.toString(result);
 			Object error = responseMessage.getError();
-			String errorJson = MessageJsonHandler.toString(error);
+			String errorJson = jsonHandler.toString(error);
 			String format = "[Trace - %s] Received response '%s - (%s)' in %sms\nResult: %s\nError: %s\n\n\n";
 			return String.format(format, date, method, id, latencyMillis, resultJson, errorJson);
 		} else if (message instanceof NotificationMessage) {
 			NotificationMessage notificationMessage = (NotificationMessage) message;
 			String method = notificationMessage.getMethod();
 			Object params = notificationMessage.getParams();
-			String paramsJson = MessageJsonHandler.toString(params);
+			String paramsJson = jsonHandler.toString(params);
 			String format = "[Trace - %s] Received notification '%s'\nParams: %s\n\n\n";
 			return String.format(format, date, method, paramsJson);
 		} else {

org.eclipse.lsp4j.jsonrpc/src/main/java/org/eclipse/lsp4j/jsonrpc/json/MessageJsonHandler.java

@@ -11,6 +11,8 @@
  ******************************************************************************/
 package org.eclipse.lsp4j.jsonrpc.json;
 
+import com.google.gson.JsonNull;
+import com.google.gson.stream.JsonWriter;
 import java.io.IOException;
 import java.io.Reader;
 import java.io.StringReader;
@@ -48,7 +50,7 @@ public class MessageJsonHandler {
 	public static final JsonRpcMethod CANCEL_METHOD = JsonRpcMethod.notification("$/cancelRequest", CancelParams.class);
 
 	private final Gson gson;
-	
+
 	private final Map<String, JsonRpcMethod> supportedMethods;
 
 	private MethodProvider methodProvider;
@@ -144,21 +146,27 @@ public String serialize(Message message) {
 	public void serialize(Message message, Writer output) throws JsonIOException {
 		gson.toJson(message, Message.class, output);
 	}
-
-
-	private static MessageJsonHandler toStringInstance;
-
+
 	/**
-	 * Perform JSON serialization of the given object using the default configuration of JSON-RPC messages
+	 * Perform JSON serialization of the given object using the configuration of JSON-RPC messages
 	 * enhanced with the pretty printing option.
 	 */
-	public static String toString(Object object) {
-		if (toStringInstance == null) {
-			toStringInstance = new MessageJsonHandler(Collections.emptyMap(), gsonBuilder -> {
-				gsonBuilder.setPrettyPrinting();
-			});
+	public String toString(Object object) {
+		StringWriter writer = new StringWriter();
+		JsonWriter jsonWriter = null;
+		try {
+			jsonWriter = gson.newJsonWriter(writer);
+			// Equivalent to set pretty printing on the gson builder
+			jsonWriter.setIndent("  ");
+		} catch (IOException e) {
+			throw new JsonIOException(e);
+		}
+		if (object != null) {
+			gson.toJson(object, object.getClass(), jsonWriter);
+		} else {
+			gson.toJson(JsonNull.INSTANCE, jsonWriter);
 		}
-		return toStringInstance.gson.toJson(object);
+		return writer.toString();
 	}
-	
+
 }

org.eclipse.lsp4j.jsonrpc/src/main/java/org/eclipse/lsp4j/jsonrpc/messages/CancelParams.java

@@ -52,11 +52,6 @@ public void setId(@NonNull int id) {
 	public void setRawId(@NonNull Either<String, Number> id) {
 		this.id = id;
 	}
-
-	@Override
-	public String toString() {
-		return MessageJsonHandler.toString(this);
-	}
 
 	@Override
 	public boolean equals(final Object obj) {

org.eclipse.lsp4j.jsonrpc/src/main/java/org/eclipse/lsp4j/jsonrpc/messages/Message.java

@@ -33,11 +33,6 @@ public void setJsonrpc(@NonNull String jsonrpc) {
 		this.jsonrpc = jsonrpc;
 	}
 
-	@Override
-	public String toString() {
-		return MessageJsonHandler.toString(this);
-	}
-
 	@Override
 	public boolean equals(final Object obj) {
 		if (this == obj)

org.eclipse.lsp4j.jsonrpc/src/main/java/org/eclipse/lsp4j/jsonrpc/messages/ResponseError.java

@@ -81,11 +81,6 @@ public ResponseError(int code, String message, Object data) {
 		this.data = data;
 	}
 
-	@Override
-	public String toString() {
-		return MessageJsonHandler.toString(this);
-	}
-
 	@Override
 	public boolean equals(final Object obj) {
 		if (this == obj)

org.eclipse.lsp4j.jsonrpc/src/test/java/org/eclipse/lsp4j/jsonrpc/test/IntegrationTest.java

@@ -18,6 +18,10 @@
 import java.io.ByteArrayOutputStream;
 import java.io.PipedInputStream;
 import java.io.PipedOutputStream;
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.concurrent.CancellationException;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
@@ -83,6 +87,16 @@ public Either<String, Integer> getEither() {
 		public void setEither(Either<String, Integer> either) {
 			this.either = either;
 		}
+
+		private Path customAdapter;
+
+		public Path getCustomAdapter() {
+			return customAdapter;
+		}
+
+		public void setCustomAdapter(Path customAdapter) {
+			this.customAdapter = customAdapter;
+		}
 	}
 
 	public static interface MyServer {
@@ -727,6 +741,62 @@ public void testValidationIssue2() throws Exception {
 				out.toString());
 	}
 
+	@Test
+	public void testMessageTracingWithCustomGsonAdapter() throws Exception {
+		// create client side
+		PipedInputStream in = new PipedInputStream();
+		PipedOutputStream out = new PipedOutputStream();
+		PipedInputStream in2 = new PipedInputStream();
+		PipedOutputStream out2 = new PipedOutputStream();
+
+		in.connect(out2);
+		out.connect(in2);
+
+		StringWriter clientTraceOut = new StringWriter();
+		StringWriter serverTraceOut = new StringWriter();
+
+		MyClient client = new MyClientImpl();
+		Launcher<MyServer> clientSideLauncher = new Launcher.Builder<MyServer>()
+			.setLocalService(client)
+			.setRemoteInterface(MyServer.class)
+			.setInput(in)
+			.setOutput(out)
+			.configureGson(gsonBuilder -> gsonBuilder.registerTypeHierarchyAdapter(Path.class, new PathTypeAdapter()))
+			.traceMessages(new PrintWriter(clientTraceOut))
+			.create();
+
+		// create server side
+		MyServer server = new MyServerImpl();
+		Launcher<MyClient> serverSideLauncher = new Launcher.Builder<MyClient>()
+			.setLocalService(server)
+			.setRemoteInterface(MyClient.class)
+			.setInput(in2)
+			.setOutput(out2)
+			.configureGson(gsonBuilder -> gsonBuilder.registerTypeHierarchyAdapter(Path.class, new PathTypeAdapter()))
+			.traceMessages(new PrintWriter(serverTraceOut))
+			.create();
+
+		clientSideLauncher.startListening();
+		serverSideLauncher.startListening();
+
+		var paramWithPath = new MyParam("FOO");
+		paramWithPath.setCustomAdapter(Paths.get("").toAbsolutePath());
+		CompletableFuture<MyParam> fooFuture = clientSideLauncher.getRemoteProxy().askServer(paramWithPath);
+		CompletableFuture<MyParam> barFuture = serverSideLauncher.getRemoteProxy().askClient(new MyParam("BAR"));
+
+		Assert.assertEquals(Paths.get("").toAbsolutePath(), fooFuture.get(TIMEOUT, TimeUnit.MILLISECONDS).getCustomAdapter());
+		Assert.assertEquals("BAR", barFuture.get(TIMEOUT, TimeUnit.MILLISECONDS).value);
+
+		Assert.assertTrue(clientTraceOut.toString().contains("Sending request 'askServer - (1)'\n"
+			+ "Params: {\n"
+			+ "  \"value\": \"FOO\",\n"
+			+ "  \"customAdapter\": \""));
+		Assert.assertTrue(serverTraceOut.toString().contains("Received request 'askServer - (1)'\n"
+			+ "Params: {\n"
+			+ "  \"value\": \"FOO\",\n"
+			+ "  \"customAdapter\": \""));
+	}
+
 	protected String getHeader(int contentLength) {
 		StringBuilder headerBuilder = new StringBuilder();
 		headerBuilder.append(CONTENT_LENGTH_HEADER).append(": ").append(contentLength).append(CRLF);