Deprecate StringUtils::trimWhitespace and variants

This commits deprecates
- StringUtils::trimWhitespace in favor of String::strip
- StringUtils::trimLeadingWhitespace in favor of String::stripLeading
- StringUtils::trimTrailingWhitespace in favor of String::stripTrailing

Closes gh-27769

spring-aop/src/main/java/org/springframework/aop/aspectj/AbstractAspectJAdvice.java

@@ -261,7 +261,7 @@ public abstract class AbstractAspectJAdvice implements Advice, AspectJPrecedence
 	public void setArgumentNamesFromStringArray(String... args) {
 		this.argumentNames = new String[args.length];
 		for (int i = 0; i < args.length; i++) {
-			this.argumentNames[i] = StringUtils.trimWhitespace(args[i]);
+			this.argumentNames[i] = args[i].strip();
 			if (!isVariableName(this.argumentNames[i])) {
 				throw new IllegalArgumentException(
 						"'argumentNames' property of AbstractAspectJAdvice contains an argument name '" +

spring-aop/src/main/java/org/springframework/aop/aspectj/AspectJAdviceParameterNameDiscoverer.java

@@ -486,7 +486,7 @@ public class AspectJAdviceParameterNameDiscoverer implements ParameterNameDiscov
 		}
 		String[] tokens = StringUtils.tokenizeToStringArray(argsSpec, ",");
 		for (int i = 0; i < tokens.length; i++) {
-			tokens[i] = StringUtils.trimWhitespace(tokens[i]);
+			tokens[i] = tokens[i].strip();
 			String varName = maybeExtractVariableName(tokens[i]);
 			if (varName != null) {
 				varNames.add(varName);

spring-aop/src/main/java/org/springframework/aop/framework/autoproxy/BeanNameAutoProxyCreator.java

@@ -25,7 +25,6 @@ import org.springframework.beans.factory.FactoryBean;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.PatternMatchUtils;
-import org.springframework.util.StringUtils;
 
 /**
  * Auto proxy creator that identifies beans to proxy via a list of names.
@@ -69,7 +68,7 @@ public class BeanNameAutoProxyCreator extends AbstractAutoProxyCreator {
 		Assert.notEmpty(beanNames, "'beanNames' must not be empty");
 		this.beanNames = new ArrayList<>(beanNames.length);
 		for (String mappedName : beanNames) {
-			this.beanNames.add(StringUtils.trimWhitespace(mappedName));
+			this.beanNames.add(mappedName.strip());
 		}
 	}
 

spring-aop/src/main/java/org/springframework/aop/support/AbstractRegexpMethodPointcut.java

@@ -24,7 +24,6 @@ import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.ObjectUtils;
-import org.springframework.util.StringUtils;
 
 /**
  * Abstract base regular expression pointcut bean. JavaBean properties are:
@@ -81,7 +80,7 @@ public abstract class AbstractRegexpMethodPointcut extends StaticMethodMatcherPo
 		Assert.notEmpty(patterns, "'patterns' must not be empty");
 		this.patterns = new String[patterns.length];
 		for (int i = 0; i < patterns.length; i++) {
-			this.patterns[i] = StringUtils.trimWhitespace(patterns[i]);
+			this.patterns[i] = patterns[i].strip();
 		}
 		initPatternRepresentation(this.patterns);
 	}
@@ -111,7 +110,7 @@ public abstract class AbstractRegexpMethodPointcut extends StaticMethodMatcherPo
 		Assert.notEmpty(excludedPatterns, "'excludedPatterns' must not be empty");
 		this.excludedPatterns = new String[excludedPatterns.length];
 		for (int i = 0; i < excludedPatterns.length; i++) {
-			this.excludedPatterns[i] = StringUtils.trimWhitespace(excludedPatterns[i]);
+			this.excludedPatterns[i] = excludedPatterns[i].strip();
 		}
 		initExcludedPatternRepresentation(this.excludedPatterns);
 	}

spring-beans/src/main/java/org/springframework/beans/factory/support/PropertiesBeanDefinitionReader.java

@@ -428,31 +428,31 @@ public class PropertiesBeanDefinitionReader extends AbstractBeanDefinitionReader
 		int beginIndex = prefixWithSep.length();
 
 		for (Map.Entry<?, ?> entry : map.entrySet()) {
-			String key = StringUtils.trimWhitespace((String) entry.getKey());
+			String key = ((String) entry.getKey()).strip();
 			if (key.startsWith(prefixWithSep)) {
 				String property = key.substring(beginIndex);
 				if (CLASS_KEY.equals(property)) {
-					className = StringUtils.trimWhitespace((String) entry.getValue());
+					className = ((String) entry.getValue()).strip();
 				}
 				else if (PARENT_KEY.equals(property)) {
-					parent = StringUtils.trimWhitespace((String) entry.getValue());
+					parent = ((String) entry.getValue()).strip();
 				}
 				else if (ABSTRACT_KEY.equals(property)) {
-					String val = StringUtils.trimWhitespace((String) entry.getValue());
+					String val = ((String) entry.getValue()).strip();
 					isAbstract = TRUE_VALUE.equals(val);
 				}
 				else if (SCOPE_KEY.equals(property)) {
 					// Spring 2.0 style
-					scope = StringUtils.trimWhitespace((String) entry.getValue());
+					scope = ((String) entry.getValue()).strip();
 				}
 				else if (SINGLETON_KEY.equals(property)) {
 					// Spring 1.2 style
-					String val = StringUtils.trimWhitespace((String) entry.getValue());
+					String val = ((String) entry.getValue()).strip();
 					scope = (!StringUtils.hasLength(val) || TRUE_VALUE.equals(val) ?
 							BeanDefinition.SCOPE_SINGLETON : BeanDefinition.SCOPE_PROTOTYPE);
 				}
 				else if (LAZY_INIT_KEY.equals(property)) {
-					String val = StringUtils.trimWhitespace((String) entry.getValue());
+					String val = ((String) entry.getValue()).strip();
 					lazyInit = TRUE_VALUE.equals(val);
 				}
 				else if (property.startsWith(CONSTRUCTOR_ARG_PREFIX)) {
@@ -469,7 +469,7 @@ public class PropertiesBeanDefinitionReader extends AbstractBeanDefinitionReader
 					// This isn't a real property, but a reference to another prototype
 					// Extract property name: property is of form dog(ref)
 					property = property.substring(0, property.length() - REF_SUFFIX.length());
-					String ref = StringUtils.trimWhitespace((String) entry.getValue());
+					String ref = ((String) entry.getValue()).strip();
 
 					// It doesn't matter if the referenced bean hasn't yet been registered:
 					// this will ensure that the reference is resolved at runtime.

spring-beans/src/main/java/org/springframework/beans/factory/xml/SimpleConstructorNamespaceHandler.java

@@ -79,8 +79,8 @@ public class SimpleConstructorNamespaceHandler implements NamespaceHandler {
 	@Override
 	public BeanDefinitionHolder decorate(Node node, BeanDefinitionHolder definition, ParserContext parserContext) {
 		if (node instanceof Attr attr) {
-			String argName = StringUtils.trimWhitespace(parserContext.getDelegate().getLocalName(attr));
-			String argValue = StringUtils.trimWhitespace(attr.getValue());
+			String argName = parserContext.getDelegate().getLocalName(attr).strip();
+			String argValue = attr.getValue().strip();
 
 			ConstructorArgumentValues cvs = definition.getBeanDefinition().getConstructorArgumentValues();
 			boolean ref = false;

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

@@ -218,7 +218,9 @@ public abstract class StringUtils {
 	 * @param str the {@code String} to check
 	 * @return the trimmed {@code String}
 	 * @see java.lang.Character#isWhitespace
+	 * @deprecated in favor of {@link String#strip()}
 	 */
+	@Deprecated
 	public static String trimWhitespace(String str) {
 		if (!hasLength(str)) {
 			return str;
@@ -255,7 +257,9 @@ public abstract class StringUtils {
 	 * @param str the {@code String} to check
 	 * @return the trimmed {@code String}
 	 * @see java.lang.Character#isWhitespace
+	 * @deprecated in favor of {@link String#stripLeading()}
 	 */
+	@Deprecated
 	public static String trimLeadingWhitespace(String str) {
 		if (!hasLength(str)) {
 			return str;
@@ -269,7 +273,9 @@ public abstract class StringUtils {
 	 * @param str the {@code String} to check
 	 * @return the trimmed {@code String}
 	 * @see java.lang.Character#isWhitespace
+	 * @deprecated in favor of {@link String#stripTrailing()}
 	 */
+	@Deprecated
 	public static String trimTrailingWhitespace(String str) {
 		if (!hasLength(str)) {
 			return str;
@@ -843,7 +849,7 @@ public abstract class StringUtils {
 			// code sans the separator between the country code and the variant.
 			int endIndexOfCountryCode = localeString.indexOf(country, language.length()) + country.length();
 			// Strip off any leading '_' and whitespace, what's left is the variant.
-			variant = trimLeadingWhitespace(localeString.substring(endIndexOfCountryCode));
+			variant = localeString.substring(endIndexOfCountryCode).stripLeading();
 			if (variant.startsWith("_")) {
 				variant = trimLeadingCharacter(variant, '_');
 			}

spring-core/src/test/java/org/springframework/util/StringUtilsTests.java

@@ -67,6 +67,7 @@ class StringUtilsTests {
 	}
 
 	@Test
+	@Deprecated
 	void trimWhitespace() {
 		assertThat(StringUtils.trimWhitespace(null)).isEqualTo(null);
 		assertThat(StringUtils.trimWhitespace("")).isEqualTo("");
@@ -97,6 +98,7 @@ class StringUtilsTests {
 	}
 
 	@Test
+	@Deprecated
 	void trimLeadingWhitespace() {
 		assertThat(StringUtils.trimLeadingWhitespace(null)).isEqualTo(null);
 		assertThat(StringUtils.trimLeadingWhitespace("")).isEqualTo("");
@@ -112,6 +114,7 @@ class StringUtilsTests {
 	}
 
 	@Test
+	@Deprecated
 	void trimTrailingWhitespace() {
 		assertThat(StringUtils.trimTrailingWhitespace(null)).isEqualTo(null);
 		assertThat(StringUtils.trimTrailingWhitespace("")).isEqualTo("");

spring-tx/src/main/java/org/springframework/transaction/config/TxAdviceBeanDefinitionParser.java

@@ -145,14 +145,14 @@ class TxAdviceBeanDefinitionParser extends AbstractSingleBeanDefinitionParser {
 	private void addRollbackRuleAttributesTo(List<RollbackRuleAttribute> rollbackRules, String rollbackForValue) {
 		String[] exceptionTypeNames = StringUtils.commaDelimitedListToStringArray(rollbackForValue);
 		for (String typeName : exceptionTypeNames) {
-			rollbackRules.add(new RollbackRuleAttribute(StringUtils.trimWhitespace(typeName)));
+			rollbackRules.add(new RollbackRuleAttribute(typeName.strip()));
 		}
 	}
 
 	private void addNoRollbackRuleAttributesTo(List<RollbackRuleAttribute> rollbackRules, String noRollbackForValue) {
 		String[] exceptionTypeNames = StringUtils.commaDelimitedListToStringArray(noRollbackForValue);
 		for (String typeName : exceptionTypeNames) {
-			rollbackRules.add(new NoRollbackRuleAttribute(StringUtils.trimWhitespace(typeName)));
+			rollbackRules.add(new NoRollbackRuleAttribute(typeName.strip()));
 		}
 	}
 

spring-tx/src/main/java/org/springframework/transaction/interceptor/TransactionAttributeEditor.java

@@ -54,7 +54,7 @@ public class TransactionAttributeEditor extends PropertyEditorSupport {
 			RuleBasedTransactionAttribute attr = new RuleBasedTransactionAttribute();
 			for (String token : tokens) {
 				// Trim leading and trailing whitespace.
-				String trimmedToken = StringUtils.trimWhitespace(token.trim());
+				String trimmedToken = token.strip();
 				// Check whether token contains illegal whitespace within text.
 				if (StringUtils.containsWhitespace(trimmedToken)) {
 					throw new IllegalArgumentException(