Apply SingleSpaceSeparator Checkstyle module

This commit also fixes its violations.

Closes gh-31469

Author: izeye

spring-aop/src/main/java/org/aopalliance/intercept/ConstructorInterceptor.java

@@ -43,7 +43,7 @@
  *
  * @author Rod Johnson
  */
-public interface ConstructorInterceptor extends Interceptor  {
+public interface ConstructorInterceptor extends Interceptor {
 
 	/**
 	 * Implement this method to perform extra treatments before and

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

@@ -307,7 +307,7 @@ protected void setReturningNameNoCheck(String name) {
 				this.discoveredReturningType = ClassUtils.forName(name, getAspectClassLoader());
 			}
 			catch (Throwable ex) {
-				throw new IllegalArgumentException("Returning name '" + name  +
+				throw new IllegalArgumentException("Returning name '" + name +
 						"' is neither a valid argument name nor the fully-qualified " +
 						"name of a Java type on the classpath. Root cause: " + ex);
 			}
@@ -342,7 +342,7 @@ protected void setThrowingNameNoCheck(String name) {
 				this.discoveredThrowingType = ClassUtils.forName(name, getAspectClassLoader());
 			}
 			catch (Throwable ex) {
-				throw new IllegalArgumentException("Throwing name '" + name  +
+				throw new IllegalArgumentException("Throwing name '" + name +
 						"' is neither a valid argument name nor the fully-qualified " +
 						"name of a Java type on the classpath. Root cause: " + ex);
 			}

spring-aop/src/test/java/org/springframework/aop/config/AopNamespaceHandlerEventTests.java

@@ -45,8 +45,8 @@ class AopNamespaceHandlerEventTests {
 
 	private static final Class<?> CLASS = AopNamespaceHandlerEventTests.class;
 
-	private static final Resource CONTEXT =  qualifiedResource(CLASS, "context.xml");
-	private static final Resource POINTCUT_EVENTS_CONTEXT =  qualifiedResource(CLASS, "pointcutEvents.xml");
+	private static final Resource CONTEXT = qualifiedResource(CLASS, "context.xml");
+	private static final Resource POINTCUT_EVENTS_CONTEXT = qualifiedResource(CLASS, "pointcutEvents.xml");
 	private static final Resource POINTCUT_REF_CONTEXT = qualifiedResource(CLASS, "pointcutRefEvents.xml");
 	private static final Resource DIRECT_POINTCUT_EVENTS_CONTEXT = qualifiedResource(CLASS, "directPointcutEvents.xml");
 

spring-aspects/src/test/java/org/springframework/cache/config/AnnotatedClassCacheableService.java

@@ -209,7 +209,7 @@ public Object multiCache(Object arg1) {
 	}
 
 	@Override
-	@Caching(evict = { @CacheEvict("primary"), @CacheEvict(cacheNames = "secondary", key = "#a0"),  @CacheEvict(cacheNames = "primary", key = "#p0 + 'A'") })
+	@Caching(evict = { @CacheEvict("primary"), @CacheEvict(cacheNames = "secondary", key = "#a0"), @CacheEvict(cacheNames = "primary", key = "#p0 + 'A'") })
 	public Object multiEvict(Object arg1) {
 		return this.counter.getAndIncrement();
 	}

spring-aspects/src/test/java/org/springframework/context/annotation/aspectj/AnnotationBeanConfigurerTests.java

@@ -37,7 +37,7 @@ public class AnnotationBeanConfigurerTests {
 
 	@Test
 	public void injection() {
-		try (AnnotationConfigApplicationContext context = new  AnnotationConfigApplicationContext(Config.class)) {
+		try (AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(Config.class)) {
 			ShouldBeConfiguredBySpring myObject = new ShouldBeConfiguredBySpring();
 			assertThat(myObject.getName()).isEqualTo("Rod");
 		}

spring-beans/src/main/java/org/springframework/beans/factory/groovy/GroovyBeanDefinitionReader.java

@@ -476,7 +476,7 @@ private GroovyBeanDefinitionWrapper invokeBeanDefiningMethod(String beanName, Ob
 					this.currentBeanDefinition = new GroovyBeanDefinitionWrapper(beanName, beanClass);
 				}
 			}
-			else  {
+			else {
 				this.currentBeanDefinition = new GroovyBeanDefinitionWrapper(
 						beanName, beanClass, resolveConstructorArguments(args, 1, args.length));
 			}

spring-beans/src/test/java/org/springframework/beans/factory/DefaultListableBeanFactoryTests.java

@@ -1161,7 +1161,7 @@ void registerExistingSingletonWithNameOverriding() {
 		assertThat(lbf.getBean("singletonObject")).isEqualTo(singletonObject);
 		assertThat(test.getSpouse()).isEqualTo(singletonObject);
 
-		Map<?, ?>  beansOfType = lbf.getBeansOfType(TestBean.class, false, true);
+		Map<?, ?> beansOfType = lbf.getBeansOfType(TestBean.class, false, true);
 		assertThat(beansOfType).hasSize(2);
 		assertThat(beansOfType.containsValue(test)).isTrue();
 		assertThat(beansOfType.containsValue(singletonObject)).isTrue();

spring-beans/src/test/java/org/springframework/beans/factory/aot/DefaultBeanRegistrationCodeFragmentsTests.java

@@ -218,7 +218,7 @@ public CodeBlock generateInstanceSupplierCode(GenerationContext generationContex
 	}
 
 	private BeanRegistrationCodeFragments createCustomCodeFragments(RegisteredBean registeredBean, UnaryOperator<BeanRegistrationCodeFragments> customFragments) {
-		BeanRegistrationAotContribution aotContribution =  BeanRegistrationAotContribution.
+		BeanRegistrationAotContribution aotContribution = BeanRegistrationAotContribution.
 				withCustomCodeFragments(customFragments);
 		BeanRegistrationCodeFragments defaultCodeFragments = createInstance(registeredBean);
 		return aotContribution.customizeBeanRegistrationCodeFragments(

spring-beans/src/test/java/org/springframework/beans/factory/parsing/NullSourceExtractorTests.java

@@ -28,7 +28,7 @@ public class NullSourceExtractorTests {
 
 	@Test
 	public void testPassThroughContract() throws Exception {
-		Object source  = new Object();
+		Object source = new Object();
 		Object extractedSource = new NullSourceExtractor().extractSource(source, null);
 		assertThat(extractedSource).as("The contract of NullSourceExtractor states that the extraction *always* return null").isNull();
 	}

spring-beans/src/test/java/org/springframework/beans/factory/parsing/PassThroughSourceExtractorTests.java

@@ -30,7 +30,7 @@ public class PassThroughSourceExtractorTests {
 
 	@Test
 	public void testPassThroughContract() throws Exception {
-		Object source  = new Object();
+		Object source = new Object();
 		Object extractedSource = new PassThroughSourceExtractor().extractSource(source, null);
 		assertThat(extractedSource).as("The contract of PassThroughSourceExtractor states that the supplied " +
 				"source object *must* be returned as-is").isSameAs(source);