Polishing

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -272,8 +272,7 @@ public class DefaultStompSession implements ConnectionHandlingStompSession {
 	}
 
 	private boolean isEmpty(@Nullable Object payload) {
-		return payload == null || StringUtils.isEmpty(payload) ||
+		return (StringUtils.isEmpty(payload) || (payload instanceof byte[] && ((byte[]) payload).length == 0));
-				(payload instanceof byte[] && ((byte[]) payload).length == 0);
 	}
 
 	private void execute(Message<byte[]> message) {

spring-messaging/src/main/java/org/springframework/messaging/support/NativeMessageHeaderAccessor.java

@@ -82,7 +82,7 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 
 
 	/**
-	 * Sub-classes can use this method to access the "native" headers sub-map.
+	 * Subclasses can use this method to access the "native" headers sub-map.
 	 */
 	@SuppressWarnings("unchecked")
 	@Nullable
@@ -139,6 +139,7 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 
 	/**
 	 * Whether the native header map contains the give header name.
+	 * @param headerName the name of the header
 	 */
 	public boolean containsNativeHeader(String headerName) {
 		Map<String, List<String>> map = getNativeHeaders();
@@ -146,7 +147,9 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 	}
 
 	/**
-	 * Return the values for the specified native header, if present.
+	 * Return all values for the specified native header, if present.
+	 * @param headerName the name of the header
+	 * @return the associated values, or {@code null} if none
 	 */
 	@Nullable
 	public List<String> getNativeHeader(String headerName) {
@@ -156,13 +159,15 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 
 	/**
 	 * Return the first value for the specified native header, if present.
+	 * @param headerName the name of the header
+	 * @return the associated value, or {@code null} if none
 	 */
 	@Nullable
 	public String getFirstNativeHeader(String headerName) {
 		Map<String, List<String>> map = getNativeHeaders();
 		if (map != null) {
 			List<String> values = map.get(headerName);
-			if (values != null) {
+			if (!CollectionUtils.isEmpty(values)) {
 				return values.get(0);
 			}
 		}
@@ -200,6 +205,8 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 	 * Add the specified native header value to existing values.
 	 * <p>In order for this to work, the accessor must be {@link #isMutable()
 	 * mutable}. See {@link MessageHeaderAccessor} for details.
+	 * @param name the name of the header
+	 * @param value the header value to set
 	 */
 	public void addNativeHeader(String name, @Nullable String value) {
 		Assert.state(isMutable(), "Already immutable");
@@ -216,6 +223,10 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 		setModified(true);
 	}
 
+	/**
+	 * Add the specified native headers to existing values.
+	 * @param headers the headers to set
+	 */
 	public void addNativeHeaders(@Nullable MultiValueMap<String, String> headers) {
 		if (headers == null) {
 			return;
@@ -227,24 +238,34 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 	 * Remove the specified native header value replacing existing values.
 	 * <p>In order for this to work, the accessor must be {@link #isMutable()
 	 * mutable}. See {@link MessageHeaderAccessor} for details.
+	 * @param headerName the name of the header
+	 * @return the associated values, or {@code null} if the header was not present
 	 */
 	@Nullable
-	public List<String> removeNativeHeader(String name) {
+	public List<String> removeNativeHeader(String headerName) {
 		Assert.state(isMutable(), "Already immutable");
 		Map<String, List<String>> nativeHeaders = getNativeHeaders();
-		if (nativeHeaders == null) {
+		if (CollectionUtils.isEmpty(nativeHeaders)) {
 			return null;
 		}
-		return nativeHeaders.remove(name);
+		return nativeHeaders.remove(headerName);
 	}
 
+
+	/**
+	 * Return the first value for the specified native header,
+	 * or {@code null} if none.
+	 * @param headerName the name of the header
+	 * @param headers the headers map to introspect
+	 * @return the associated value, or {@code null} if none
+	 */
 	@SuppressWarnings("unchecked")
 	@Nullable
 	public static String getFirstNativeHeader(String headerName, Map<String, Object> headers) {
 		Map<String, List<String>> map = (Map<String, List<String>>) headers.get(NATIVE_HEADERS);
 		if (map != null) {
 			List<String> values = map.get(headerName);
-			if (values != null) {
+			if (!CollectionUtils.isEmpty(values)) {
 				return values.get(0);
 			}
 		}

spring-test/src/main/java/org/springframework/test/web/servlet/request/MockHttpServletRequestBuilder.java

@@ -700,8 +700,8 @@ public class MockHttpServletRequestBuilder
 
 		String query = this.url.getRawQuery();
 		if (!this.queryParams.isEmpty()) {
-			String s = UriComponentsBuilder.newInstance().queryParams(this.queryParams).build().encode().getQuery();
+			String str = UriComponentsBuilder.newInstance().queryParams(this.queryParams).build().encode().getQuery();
-			query = StringUtils.isEmpty(query) ? s : query + "&" + s;
+			query = StringUtils.hasLength(query) ? (query + "&" + str) : str;
 		}
 		if (query != null) {
 			request.setQueryString(query);

spring-web/src/main/java/org/springframework/http/ResponseCookie.java

@@ -245,10 +245,10 @@ public final class ResponseCookie extends HttpCookie {
 
 			@Nullable
 			private String initDomain(String domain) {
-				if (lenient && !StringUtils.isEmpty(domain)) {
+				if (lenient && StringUtils.hasLength(domain)) {
-					String s = domain.trim();
+					String str = domain.trim();
-					if (s.startsWith("\"") && s.endsWith("\"")) {
+					if (str.startsWith("\"") && str.endsWith("\"")) {
-						if (s.substring(1, s.length() - 1).trim().isEmpty()) {
+						if (str.substring(1, str.length() - 1).trim().isEmpty()) {
 							return null;
 						}
 					}

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

@@ -38,7 +38,6 @@ import org.springframework.core.io.buffer.PooledDataBuffer;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.MediaType;
-import org.springframework.util.Assert;
 
 /**
  * {@link ClientHttpRequest} implementation for the Jetty ReactiveStreams HTTP client.
@@ -62,9 +61,7 @@ class JettyClientHttpRequest extends AbstractClientHttpRequest {
 
 	@Override
 	public HttpMethod getMethod() {
-		HttpMethod method = HttpMethod.resolve(this.jettyRequest.getMethod());
+		return HttpMethod.valueOf(this.jettyRequest.getMethod());
-		Assert.state(method != null, "Method must not be null");
-		return method;
 	}
 
 	@Override
@@ -117,7 +114,6 @@ class JettyClientHttpRequest extends AbstractClientHttpRequest {
 			public void succeeded() {
 				DataBufferUtils.release(buffer);
 			}
-
 			@Override
 			public void failed(Throwable x) {
 				DataBufferUtils.release(buffer);