Replace anonymous inner classes with lambda expressions

Closes gh-25319

Author: May

spring-web/src/main/java/org/springframework/http/client/SimpleBufferingAsyncClientHttpRequest.java

@@ -76,27 +76,24 @@ public URI getURI() {
 	protected ListenableFuture<ClientHttpResponse> executeInternal(
 			final HttpHeaders headers, final byte[] bufferedOutput) throws IOException {
 
-		return this.taskExecutor.submitListenable(new Callable<ClientHttpResponse>() {
-			@Override
-			public ClientHttpResponse call() throws Exception {
-				SimpleBufferingClientHttpRequest.addHeaders(connection, headers);
-				// JDK <1.8 doesn't support getOutputStream with HTTP DELETE
-				if (getMethod() == HttpMethod.DELETE && bufferedOutput.length == 0) {
-					connection.setDoOutput(false);
-				}
-				if (connection.getDoOutput() && outputStreaming) {
-					connection.setFixedLengthStreamingMode(bufferedOutput.length);
-				}
-				connection.connect();
-				if (connection.getDoOutput()) {
-					FileCopyUtils.copy(bufferedOutput, connection.getOutputStream());
-				}
-				else {
-					// Immediately trigger the request in a no-output scenario as well
-					connection.getResponseCode();
-				}
-				return new SimpleClientHttpResponse(connection);
+		return this.taskExecutor.submitListenable(() -> {
+			SimpleBufferingClientHttpRequest.addHeaders(connection, headers);
+			// JDK <1.8 doesn't support getOutputStream with HTTP DELETE
+			if (getMethod() == HttpMethod.DELETE && bufferedOutput.length == 0) {
+				connection.setDoOutput(false);
 			}
+			if (connection.getDoOutput() && outputStreaming) {
+				connection.setFixedLengthStreamingMode(bufferedOutput.length);
+			}
+			connection.connect();
+			if (connection.getDoOutput()) {
+				FileCopyUtils.copy(bufferedOutput, connection.getOutputStream());
+			}
+			else {
+				// Immediately trigger the request in a no-output scenario as well
+				connection.getResponseCode();
+			}
+			return new SimpleClientHttpResponse(connection);
 		});
 	}
 

spring-web/src/main/java/org/springframework/http/client/SimpleStreamingAsyncClientHttpRequest.java

@@ -103,25 +103,22 @@ protected OutputStream getBodyInternal(HttpHeaders headers) throws IOException {
 
 	@Override
 	protected ListenableFuture<ClientHttpResponse> executeInternal(final HttpHeaders headers) throws IOException {
-		return this.taskExecutor.submitListenable(new Callable<ClientHttpResponse>() {
-			@Override
-			public ClientHttpResponse call() throws Exception {
-				try {
-					if (body != null) {
-						body.close();
-					}
-					else {
-						SimpleBufferingClientHttpRequest.addHeaders(connection, headers);
-						connection.connect();
-						// Immediately trigger the request in a no-output scenario as well
-						connection.getResponseCode();
-					}
+		return this.taskExecutor.submitListenable(() -> {
+			try {
+				if (body != null) {
+					body.close();
 				}
-				catch (IOException ex) {
-					// ignore
+				else {
+					SimpleBufferingClientHttpRequest.addHeaders(connection, headers);
+					connection.connect();
+					// Immediately trigger the request in a no-output scenario as well
+					connection.getResponseCode();
 				}
-				return new SimpleClientHttpResponse(connection);
 			}
+			catch (IOException ex) {
+				// ignore
+			}
+			return new SimpleClientHttpResponse(connection);
 		});
 
 	}