Polishing

spring-aop/src/main/java/org/springframework/aop/aspectj/annotation/AspectMetadata.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -124,10 +124,16 @@ public AspectMetadata(Class<?> aspectClass, String aspectName) {
 	 * Extract contents from String of form {@code pertarget(contents)}.
 	 */
 	private String findPerClause(Class<?> aspectClass) {
-		String str = aspectClass.getAnnotation(Aspect.class).value();
-		int beginIndex = str.indexOf('(') + 1;
-		int endIndex = str.length() - 1;
-		return str.substring(beginIndex, endIndex);
+		Aspect ann = aspectClass.getAnnotation(Aspect.class);
+		if (ann == null) {
+			return "";
+		}
+		String value = ann.value();
+		int beginIndex = value.indexOf('(');
+		if (beginIndex < 0) {
+			return "";
+		}
+		return value.substring(beginIndex + 1, value.length() - 1);
 	}
 
 

spring-core/src/main/java/org/springframework/util/MultiValueMapAdapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -59,7 +59,7 @@ public MultiValueMapAdapter(Map<K, List<V>> targetMap) {
 	@Nullable
 	public V getFirst(K key) {
 		List<V> values = this.targetMap.get(key);
-		return (values != null && !values.isEmpty() ? values.get(0) : null);
+		return (!CollectionUtils.isEmpty(values) ? values.get(0) : null);
 	}
 
 	@Override
@@ -95,7 +95,7 @@ public void setAll(Map<K, V> values) {
 	public Map<K, V> toSingleValueMap() {
 		Map<K, V> singleValueMap = CollectionUtils.newLinkedHashMap(this.targetMap.size());
 		this.targetMap.forEach((key, values) -> {
-			if (values != null && !values.isEmpty()) {
+			if (!CollectionUtils.isEmpty(values)) {
 				singleValueMap.put(key, values.get(0));
 			}
 		});

spring-core/src/main/java/org/springframework/util/StringUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -123,7 +123,7 @@ public static boolean isEmpty(@Nullable Object str) {
 	 * @see #hasText(CharSequence)
 	 */
 	public static boolean hasLength(@Nullable CharSequence str) {
-		return (str != null && str.length() > 0);
+		return (str != null && !str.isEmpty());  // as of JDK 15
 	}
 
 	/**
@@ -791,6 +791,7 @@ public static boolean pathEquals(String path1, String path2) {
 	 * and {@code "0"} through {@code "9"} stay the same.</li>
 	 * <li>Special characters {@code "-"}, {@code "_"}, {@code "."}, and {@code "*"} stay the same.</li>
 	 * <li>A sequence "{@code %<i>xy</i>}" is interpreted as a hexadecimal representation of the character.</li>
+	 * <li>For all other characters (including those already decoded), the output is undefined.</li>
 	 * </ul>
 	 * @param source the encoded String
 	 * @param charset the character set
@@ -839,7 +840,7 @@ public static String uriDecode(String source, Charset charset) {
 	 * the {@link Locale#toString} format as well as BCP 47 language tags as
 	 * specified by {@link Locale#forLanguageTag}.
 	 * @param localeValue the locale value: following either {@code Locale's}
-	 * {@code toString()} format ("en", "en_UK", etc), also accepting spaces as
+	 * {@code toString()} format ("en", "en_UK", etc.), also accepting spaces as
 	 * separators (as an alternative to underscores), or BCP 47 (e.g. "en-UK")
 	 * @return a corresponding {@code Locale} instance, or {@code null} if none
 	 * @throws IllegalArgumentException in case of an invalid locale specification
@@ -868,15 +869,15 @@ public static Locale parseLocale(String localeValue) {
 	 * <p><b>Note: This delegate does not accept the BCP 47 language tag format.
 	 * Please use {@link #parseLocale} for lenient parsing of both formats.</b>
 	 * @param localeString the locale {@code String}: following {@code Locale's}
-	 * {@code toString()} format ("en", "en_UK", etc), also accepting spaces as
+	 * {@code toString()} format ("en", "en_UK", etc.), also accepting spaces as
 	 * separators (as an alternative to underscores)
 	 * @return a corresponding {@code Locale} instance, or {@code null} if none
 	 * @throws IllegalArgumentException in case of an invalid locale specification
 	 */
 	@SuppressWarnings("deprecation")  // for Locale constructors on JDK 19
 	@Nullable
 	public static Locale parseLocaleString(String localeString) {
-		if (localeString.equals("")) {
+		if (localeString.isEmpty()) {
 			return null;
 		}
 

spring-jdbc/src/main/java/org/springframework/jdbc/support/rowset/ResultSetWrappingSqlRowSet.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -32,7 +32,7 @@
 import org.springframework.util.CollectionUtils;
 
 /**
- * The default implementation of Spring's {@link SqlRowSet} interface, wrapping a
+ * The common implementation of Spring's {@link SqlRowSet} interface, wrapping a
  * {@link java.sql.ResultSet}, catching any {@link SQLException SQLExceptions} and
  * translating them to a corresponding Spring {@link InvalidResultSetAccessException}.
  *

spring-jms/src/main/java/org/springframework/jms/core/JmsMessagingTemplate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -189,11 +189,6 @@ public void send(Message<?> message) {
 		}
 	}
 
-	@Override
-	public void convertAndSend(Object payload) throws MessagingException {
-		convertAndSend(payload, null);
-	}
-
 	@Override
 	public void convertAndSend(Object payload, @Nullable MessagePostProcessor postProcessor) throws MessagingException {
 		Destination defaultDestination = getDefaultDestination();

spring-jms/src/main/java/org/springframework/jms/core/JmsOperations.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -290,7 +290,7 @@ void convertAndSend(String destinationName, Object message, MessagePostProcessor
 	 * <p>This method should be used carefully, since it will block the thread
 	 * until the message becomes available or until the timeout value is exceeded.
 	 * <p>This will only work with a default destination specified!
-	 * @return the message produced for the consumer or {@code null} if the timeout expires.
+	 * @return the message produced for the consumer, or {@code null} if the timeout expires
 	 * @throws JmsException checked JMSException converted to unchecked
 	 */
 	@Nullable
@@ -303,7 +303,7 @@ void convertAndSend(String destinationName, Object message, MessagePostProcessor
 	 * <p>This method should be used carefully, since it will block the thread
 	 * until the message becomes available or until the timeout value is exceeded.
 	 * @param destination the destination to receive a message from
-	 * @return the message produced for the consumer or {@code null} if the timeout expires.
+	 * @return the message produced for the consumer, or {@code null} if the timeout expires
 	 * @throws JmsException checked JMSException converted to unchecked
 	 */
 	@Nullable
@@ -317,7 +317,7 @@ void convertAndSend(String destinationName, Object message, MessagePostProcessor
 	 * until the message becomes available or until the timeout value is exceeded.
 	 * @param destinationName the name of the destination to send this message to
 	 * (to be resolved to an actual destination by a DestinationResolver)
-	 * @return the message produced for the consumer or {@code null} if the timeout expires.
+	 * @return the message produced for the consumer, or {@code null} if the timeout expires
 	 * @throws JmsException checked JMSException converted to unchecked
 	 */
 	@Nullable
@@ -332,7 +332,7 @@ void convertAndSend(String destinationName, Object message, MessagePostProcessor
 	 * <p>This will only work with a default destination specified!
 	 * @param messageSelector the JMS message selector expression (or {@code null} if none).
 	 * See the JMS specification for a detailed definition of selector expressions.
-	 * @return the message produced for the consumer or {@code null} if the timeout expires.
+	 * @return the message produced for the consumer, or {@code null} if the timeout expires
 	 * @throws JmsException checked JMSException converted to unchecked
 	 */
 	@Nullable
@@ -347,7 +347,7 @@ void convertAndSend(String destinationName, Object message, MessagePostProcessor
 	 * @param destination the destination to receive a message from
 	 * @param messageSelector the JMS message selector expression (or {@code null} if none).
 	 * See the JMS specification for a detailed definition of selector expressions.
-	 * @return the message produced for the consumer or {@code null} if the timeout expires.
+	 * @return the message produced for the consumer, or {@code null} if the timeout expires
 	 * @throws JmsException checked JMSException converted to unchecked
 	 */
 	@Nullable
@@ -363,7 +363,7 @@ void convertAndSend(String destinationName, Object message, MessagePostProcessor
 	 * (to be resolved to an actual destination by a DestinationResolver)
 	 * @param messageSelector the JMS message selector expression (or {@code null} if none).
 	 * See the JMS specification for a detailed definition of selector expressions.
-	 * @return the message produced for the consumer or {@code null} if the timeout expires.
+	 * @return the message produced for the consumer, or {@code null} if the timeout expires
 	 * @throws JmsException checked JMSException converted to unchecked
 	 */
 	@Nullable

spring-messaging/src/main/java/org/springframework/messaging/core/AbstractMessageSendingTemplate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -168,8 +168,7 @@ protected Message<?> doConvert(Object payload, @Nullable Map<String, Object> hea
 
 		Map<String, Object> headersToUse = processHeadersToSend(headers);
 		if (headersToUse != null) {
-			messageHeaders = (headersToUse instanceof MessageHeaders _messageHeaders ?
-					_messageHeaders : new MessageHeaders(headersToUse));
+			messageHeaders = (headersToUse instanceof MessageHeaders mh ? mh : new MessageHeaders(headersToUse));
 		}
 
 		MessageConverter converter = getMessageConverter();

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -277,7 +277,6 @@ public static <T> ResponseEntity<T> of(Optional<T> body) {
 	 */
 	public static HeadersBuilder<?> of(ProblemDetail body) {
 		return new DefaultBuilder(body.getStatus()) {
-
 			@SuppressWarnings("unchecked")
 			@Override
 			public <T> ResponseEntity<T> build() {

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -124,7 +124,6 @@ public Mono<Void> setComplete() {
 	@Override
 	protected void applyHeaders() {
 		HttpHeaders headers = getHeaders();
-
 		headers.entrySet()
 				.stream()
 				.filter(entry -> !HttpHeaders.CONTENT_LENGTH.equals(entry.getKey()))
@@ -133,7 +132,6 @@ protected void applyHeaders() {
 		if (!this.httpRequest.containsHeader(HttpHeaders.ACCEPT)) {
 			this.httpRequest.addHeader(HttpHeaders.ACCEPT, MediaType.ALL_VALUE);
 		}
-
 		this.contentLength = headers.getContentLength();
 	}
 
@@ -144,7 +142,6 @@ protected void applyCookies() {
 		}
 
 		CookieStore cookieStore = this.context.getCookieStore();
-
 		getCookies().values()
 				.stream()
 				.flatMap(Collection::stream)

spring-webmvc/src/main/java/org/springframework/web/servlet/support/AbstractFlashMapManager.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -220,7 +220,7 @@ public final void saveOutputFlashMap(FlashMap flashMap, HttpServletRequest reque
 
 	@Nullable
 	private String decodeAndNormalizePath(@Nullable String path, HttpServletRequest request) {
-		if (path != null && !path.isEmpty()) {
+		if (StringUtils.hasLength(path)) {
 			path = getUrlPathHelper().decodeRequestString(request, path);
 			if (path.charAt(0) != '/') {
 				String requestUri = getUrlPathHelper().getRequestUri(request);