Apply SingleSpaceSeparator Checkstyle module

This commit also fixes its violations.

Closes gh-31469

spring-context/src/main/java/org/springframework/cache/interceptor/AbstractCacheResolver.java

@@ -73,7 +73,7 @@ public abstract class AbstractCacheResolver implements CacheResolver, Initializi
 	}
 
 	@Override
-	public void afterPropertiesSet()  {
+	public void afterPropertiesSet() {
 		Assert.notNull(this.cacheManager, "CacheManager is required");
 	}
 

spring-context/src/main/java/org/springframework/cache/interceptor/CacheInterceptor.java

@@ -84,7 +84,7 @@ public class CacheInterceptor extends CacheAspectSupport implements MethodInterc
 	private static class KotlinDelegate {
 
 		public static Publisher<?> invokeSuspendingFunction(Method method, Object target, Object... args) {
-			Continuation<?>  continuation = (Continuation<?>) args[args.length - 1];
+			Continuation<?> continuation = (Continuation<?>) args[args.length - 1];
 			CoroutineContext coroutineContext = continuation.getContext().minusKey(Job.Key);
 			return CoroutinesUtils.invokeSuspendingFunction(coroutineContext, method, target, args);
 		}

spring-context/src/main/java/org/springframework/format/datetime/DateTimeFormatAnnotationFormatterFactory.java

@@ -37,7 +37,7 @@ import org.springframework.util.StringUtils;
  * @author Sam Brannen
  * @since 3.2
  */
-public class DateTimeFormatAnnotationFormatterFactory  extends EmbeddedValueResolutionSupport
+public class DateTimeFormatAnnotationFormatterFactory extends EmbeddedValueResolutionSupport
 		implements AnnotationFormatterFactory<DateTimeFormat> {
 
 	private static final Set<Class<?>> FIELD_TYPES = Set.of(Date.class, Calendar.class, Long.class);

spring-context/src/main/java/org/springframework/scheduling/concurrent/ThreadPoolExecutorFactoryBean.java

@@ -158,7 +158,7 @@ public class ThreadPoolExecutorFactoryBean extends ExecutorConfigurationSupport
 			ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler) {
 
 		BlockingQueue<Runnable> queue = createQueue(this.queueCapacity);
-		ThreadPoolExecutor executor  = createExecutor(this.corePoolSize, this.maxPoolSize,
+		ThreadPoolExecutor executor = createExecutor(this.corePoolSize, this.maxPoolSize,
 				this.keepAliveSeconds, queue, threadFactory, rejectedExecutionHandler);
 		if (this.allowCoreThreadTimeOut) {
 			executor.allowCoreThreadTimeOut(true);

spring-context/src/main/java/org/springframework/scheduling/support/BitsCronField.java

@@ -247,7 +247,7 @@ final class BitsCronField extends CronField {
 	}
 
 	private void clearBit(int index) {
-		this.bits &=  ~(1L << index);
+		this.bits &= ~(1L << index);
 	}
 
 	@Override

spring-context/src/main/java/org/springframework/validation/DataBinder.java

@@ -949,7 +949,7 @@ public class DataBinder implements PropertyEditorRegistry, TypeConverter {
 
 				if (value == null && !BeanUtils.isSimpleValueType(param.nestedIfOptional().getNestedParameterType())) {
 					ResolvableType type = ResolvableType.forMethodParameter(param);
-					args[i]  = createObject(type, paramPath + ".", valueResolver);
+					args[i] = createObject(type, paramPath + ".", valueResolver);
 				}
 				else {
 					try {

spring-context/src/main/java/org/springframework/validation/beanvalidation/MethodValidationAdapter.java

@@ -345,7 +345,7 @@ public class MethodValidationAdapter implements MethodValidator {
 	}
 
 	private MethodParameter initMethodParameter(Method method, int index) {
-		MethodParameter	parameter = new MethodParameter(method, index);
+		MethodParameter parameter = new MethodParameter(method, index);
 		parameter.initParameterNameDiscovery(this.parameterNameDiscoverer);
 		return parameter;
 	}