Prepare for Sinks API updates in Reactor

See reactor/reactor-core#2374
All usages of this API are in tests, which are not checking overflow or
concurrent emissions - so a simple replacement with `try***` equivalents
is fine.

spring-messaging/src/test/java/org/springframework/messaging/rsocket/RSocketBufferLeakTests.java

@@ -246,7 +246,7 @@ class RSocketBufferLeakTests {
 		void checkForLeaks() {
 			this.rsockets.stream().map(PayloadSavingDecorator::getPayloads)
 					.forEach(payloadInfoProcessor -> {
-						payloadInfoProcessor.emitComplete();
+						payloadInfoProcessor.tryEmitComplete();
 						payloadInfoProcessor.asFlux()
 								.doOnNext(this::checkForLeak)
 								.blockLast();
@@ -328,7 +328,7 @@ class RSocketBufferLeakTests {
 			}
 
 			private io.rsocket.Payload addPayload(io.rsocket.Payload payload) {
-				this.payloads.emitNext(new PayloadLeakInfo(payload));
+				this.payloads.tryEmitNext(new PayloadLeakInfo(payload));
 				return payload;
 			}
 

spring-messaging/src/test/java/org/springframework/messaging/rsocket/RSocketClientToServerIntegrationTests.java

@@ -231,7 +231,7 @@ public class RSocketClientToServerIntegrationTests {
 
 		@MessageMapping("receive")
 		void receive(String payload) {
-			this.fireForgetPayloads.emitNext(payload);
+			this.fireForgetPayloads.tryEmitNext(payload);
 		}
 
 		@MessageMapping("echo")
@@ -273,7 +273,7 @@ public class RSocketClientToServerIntegrationTests {
 
 		@ConnectMapping("foo-updates")
 		public void handleMetadata(@Header("foo") String foo) {
-			this.metadataPushPayloads.emitNext(foo);
+			this.metadataPushPayloads.tryEmitNext(foo);
 		}
 
 		@MessageExceptionHandler

spring-messaging/src/test/java/org/springframework/messaging/rsocket/RSocketServerToClientIntegrationTests.java

@@ -219,7 +219,7 @@ class RSocketServerToClientIntegrationTests {
 
 		@MessageMapping("receive")
 		void receive(String payload) {
-			this.fireForgetPayloads.emitNext(payload);
+			this.fireForgetPayloads.tryEmitNext(payload);
 		}
 
 		@MessageMapping("echo")

spring-messaging/src/test/java/org/springframework/messaging/simp/annotation/support/SimpAnnotationMethodMessageHandlerTests.java

@@ -371,7 +371,7 @@ public class SimpAnnotationMethodMessageHandlerTests {
 		this.messageHandler.handleMessage(message);
 
 		assertThat(controller.fluxSink).isNotNull();
-		controller.fluxSink.emitNext("foo");
+		controller.fluxSink.tryEmitNext("foo");
 
 		verify(this.converter, never()).toMessage(any(), any(MessageHeaders.class));
 	}

spring-messaging/src/test/kotlin/org/springframework/messaging/rsocket/RSocketClientToServerCoroutinesIntegrationTests.kt

@@ -149,13 +149,13 @@ class RSocketClientToServerCoroutinesIntegrationTests {
 
 		@MessageMapping("receive")
 		fun receive(payload: String) {
-			fireForgetPayloads.emitNext(payload)
+			fireForgetPayloads.tryEmitNext(payload)
 		}
 
 		@MessageMapping("receive-async")
 		suspend fun receiveAsync(payload: String) {
 			delay(10)
-			fireForgetPayloads.emitNext(payload)
+			fireForgetPayloads.tryEmitNext(payload)
 		}
 
 		@MessageMapping("echo-async")

spring-web/src/test/java/org/springframework/http/codec/multipart/MultipartHttpMessageWriterTests.java

@@ -209,7 +209,7 @@ public class MultipartHttpMessageWriterTests extends AbstractLeakCheckingTests {
 	public void singleSubscriberWithResource() throws IOException {
 		Sinks.Many<Resource> sink = Sinks.many().unicast().onBackpressureBuffer();
 		Resource logo = new ClassPathResource("/org/springframework/http/converter/logo.jpg");
-		sink.emitNext(logo);
+		sink.tryEmitNext(logo);
 
 		MultipartBodyBuilder bodyBuilder = new MultipartBodyBuilder();
 		bodyBuilder.asyncPart("logo", sink.asFlux(), Resource.class);

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/ReactiveTypeHandlerTests.java

@@ -140,9 +140,9 @@ public class ReactiveTypeHandlerTests {
 
 		Sinks.Many<Bar> sink = Sinks.many().unicast().onBackpressureBuffer();
 		testDeferredResultSubscriber(sink.asFlux(), Flux.class, forClass(Bar.class), () -> {
-			sink.emitNext(bar1);
-			sink.emitNext(bar2);
-			sink.emitComplete();
+			sink.tryEmitNext(bar1);
+			sink.tryEmitNext(bar2);
+			sink.tryEmitComplete();
 		}, Arrays.asList(bar1, bar2));
 	}
 
@@ -195,10 +195,10 @@ public class ReactiveTypeHandlerTests {
 		EmitterHandler emitterHandler = new EmitterHandler();
 		sseEmitter.initialize(emitterHandler);
 
-		sink.emitNext("foo");
-		sink.emitNext("bar");
-		sink.emitNext("baz");
-		sink.emitComplete();
+		sink.tryEmitNext("foo");
+		sink.tryEmitNext("bar");
+		sink.tryEmitNext("baz");
+		sink.tryEmitComplete();
 
 		assertThat(emitterHandler.getValuesAsText()).isEqualTo("data:foo\n\ndata:bar\n\ndata:baz\n\n");
 	}
@@ -214,10 +214,10 @@ public class ReactiveTypeHandlerTests {
 		EmitterHandler emitterHandler = new EmitterHandler();
 		sseEmitter.initialize(emitterHandler);
 
-		sink.emitNext(ServerSentEvent.builder("foo").id("1").build());
-		sink.emitNext(ServerSentEvent.builder("bar").id("2").build());
-		sink.emitNext(ServerSentEvent.builder("baz").id("3").build());
-		sink.emitComplete();
+		sink.tryEmitNext(ServerSentEvent.builder("foo").id("1").build());
+		sink.tryEmitNext(ServerSentEvent.builder("bar").id("2").build());
+		sink.tryEmitNext(ServerSentEvent.builder("baz").id("3").build());
+		sink.tryEmitComplete();
 
 		assertThat(emitterHandler.getValuesAsText()).isEqualTo("id:1\ndata:foo\n\nid:2\ndata:bar\n\nid:3\ndata:baz\n\n");
 	}
@@ -239,9 +239,9 @@ public class ReactiveTypeHandlerTests {
 		Bar bar1 = new Bar("foo");
 		Bar bar2 = new Bar("bar");
 
-		sink.emitNext(bar1);
-		sink.emitNext(bar2);
-		sink.emitComplete();
+		sink.tryEmitNext(bar1);
+		sink.tryEmitNext(bar2);
+		sink.tryEmitComplete();
 
 		assertThat(message.getHeaders().getContentType().toString()).isEqualTo("application/x-ndjson");
 		assertThat(emitterHandler.getValues()).isEqualTo(Arrays.asList(bar1, "\n", bar2, "\n"));
@@ -256,10 +256,10 @@ public class ReactiveTypeHandlerTests {
 		EmitterHandler emitterHandler = new EmitterHandler();
 		emitter.initialize(emitterHandler);
 
-		sink.emitNext("The quick");
-		sink.emitNext(" brown fox jumps over ");
-		sink.emitNext("the lazy dog");
-		sink.emitComplete();
+		sink.tryEmitNext("The quick");
+		sink.tryEmitNext(" brown fox jumps over ");
+		sink.tryEmitNext("the lazy dog");
+		sink.tryEmitComplete();
 
 		assertThat(emitterHandler.getValuesAsText()).isEqualTo("The quick brown fox jumps over the lazy dog");
 	}

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/ResponseBodyEmitterReturnValueHandlerTests.java

@@ -233,10 +233,10 @@ public class ResponseBodyEmitterReturnValueHandlerTests {
 		assertThat(this.request.isAsyncStarted()).isTrue();
 		assertThat(this.response.getStatus()).isEqualTo(200);
 
-		sink.emitNext("foo");
-		sink.emitNext("bar");
-		sink.emitNext("baz");
-		sink.emitComplete();
+		sink.tryEmitNext("foo");
+		sink.tryEmitNext("bar");
+		sink.tryEmitNext("baz");
+		sink.tryEmitComplete();
 
 		assertThat(this.response.getContentType()).isEqualTo("text/event-stream");
 		assertThat(this.response.getContentAsString()).isEqualTo("data:foo\n\ndata:bar\n\ndata:baz\n\n");
@@ -254,8 +254,8 @@ public class ResponseBodyEmitterReturnValueHandlerTests {
 		assertThat(this.request.isAsyncStarted()).isTrue();
 
 		IllegalStateException ex = new IllegalStateException("wah wah");
-		sink.emitError(ex);
-		sink.emitComplete();
+		sink.tryEmitError(ex);
+		sink.tryEmitComplete();
 
 		WebAsyncManager asyncManager = WebAsyncUtils.getAsyncManager(this.webRequest);
 		assertThat(asyncManager.getConcurrentResult()).isSameAs(ex);
@@ -299,10 +299,10 @@ public class ResponseBodyEmitterReturnValueHandlerTests {
 		assertThat(this.request.isAsyncStarted()).isTrue();
 		assertThat(this.response.getStatus()).isEqualTo(200);
 
-		sink.emitNext("foo");
-		sink.emitNext("bar");
-		sink.emitNext("baz");
-		sink.emitComplete();
+		sink.tryEmitNext("foo");
+		sink.tryEmitNext("bar");
+		sink.tryEmitNext("baz");
+		sink.tryEmitComplete();
 
 		assertThat(this.response.getContentType()).isEqualTo("text/plain");
 		assertThat(this.response.getContentAsString()).isEqualTo("foobarbaz");