Utilizing diamond interface for concise instantiation, leveraging ins…

…tanceof pattern matching for enhanced type checking, and incorporating various improvements. Enhances code readability and embraces modern Java features.

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/UriToEntityConverter.java

@@ -66,7 +66,7 @@ public UriToEntityConverter(PersistentEntities entities, RepositoryInvokerFactor
 		Assert.notNull(invokerFactory, "RepositoryInvokerFactory must not be null");
 		Assert.notNull(conversionService, "ConversionService must not be null!");
 
-		this.convertiblePairs = new HashSet<ConvertiblePair>();
+		this.convertiblePairs = new HashSet<>();
 		this.identifierTypes = new HashSet<>();
 
 		for (TypeInformation<?> domainType : entities.getManagedTypes()) {

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/ValidationErrors.java

@@ -15,6 +15,7 @@
  */
 package org.springframework.data.rest.core;
 
+import java.io.Serial;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;
@@ -42,6 +43,7 @@
  */
 public class ValidationErrors extends AbstractPropertyBindingResult {
 
+	@Serial
 	private static final long serialVersionUID = 8141826537389141361L;
 
 	private final Object source;

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/config/EntityLookupConfiguration.java

@@ -63,7 +63,7 @@ class EntityLookupConfiguration implements EntityLookupRegistrar {
 
 	@Override
 	public <T, ID, R extends Repository<T, ?>> IdMappingRegistrar<T, R> forRepository(Class<R> type) {
-		return new MappingBuilder<T, ID, R>(type);
+		return new MappingBuilder<>(type);
 	}
 
 	@Override
@@ -115,15 +115,15 @@ private MappingBuilder(Class<R> repositoryType, Converter<T, ID> mapping) {
 		public EntityLookupRegistrar withLookup(Lookup<R, ID> lookup) {
 
 			EntityLookupConfiguration.this.lookupInformation
-					.add((LookupInformation<Object, Object, Repository<? extends Object, ?>>) new LookupInformation<T, ID, R>(
+					.add((LookupInformation<Object, Object, Repository<? extends Object, ?>>) new LookupInformation<>(
 							repositoryType, idMapping, lookup));
 
 			return EntityLookupConfiguration.this;
 		}
 
 		@Override
 		public <ID2> LookupRegistrar<T, ID2, R> withIdMapping(Converter<T, ID2> idMapping) {
-			return new MappingBuilder<T, ID2, R>(repositoryType, idMapping);
+			return new MappingBuilder<>(repositoryType, idMapping);
 		}
 	}
 
@@ -195,7 +195,7 @@ public Optional<T> lookupEntity(Object id) {
 
 			Object result = lookupInfo.getLookup().lookup(repository, id);
 
-			return Optional.class.isInstance(result) ? (Optional<T>) result : Optional.ofNullable((T) result);
+			return result instanceof Optional optional  ? optional : Optional.ofNullable((T) result);
 		}
 
 		@Override

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/config/JsonSchemaFormat.java

@@ -30,6 +30,7 @@ public enum JsonSchemaFormat {
 	EMAIL, DATE_TIME, HOSTNAME, IPV4, IPV6, URI;
 
 	@JsonValue
+	@Override
 	public String toString() {
 		return name().toLowerCase(Locale.US).replaceAll("_", "-");
 	}

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/config/MetadataConfiguration.java

@@ -29,8 +29,8 @@
  */
 public class MetadataConfiguration {
 
-	private final Map<Class<?>, JsonSchemaFormat> schemaFormats = new HashMap<Class<?>, JsonSchemaFormat>();
-	private final Map<Class<?>, Pattern> patterns = new HashMap<Class<?>, Pattern>();
+	private final Map<Class<?>, JsonSchemaFormat> schemaFormats = new HashMap<>();
+	private final Map<Class<?>, Pattern> patterns = new HashMap<>();
 	private boolean omitUnresolvableDescriptionKeys = true;
 	private boolean alpsEnabled = true;
 

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/config/ProjectionDefinitionConfiguration.java

@@ -154,8 +154,8 @@ public Map<String, Class<?>> getProjectionsFor(Class<?> sourceType) {
 		Assert.notNull(sourceType, "Source type must not be null");
 
 		Class<?> userType = ProxyUtils.getUserClass(sourceType);
-		Map<String, ProjectionDefinition> byName = new HashMap<String, ProjectionDefinition>();
-		Map<String, Class<?>> result = new HashMap<String, Class<?>>();
+		Map<String, ProjectionDefinition> byName = new HashMap<>();
+		Map<String, Class<?>> result = new HashMap<>();
 
 		for (ProjectionDefinition entry : projectionDefinitions) {
 

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/config/ResourceMapping.java

@@ -29,7 +29,7 @@ public class ResourceMapping {
 	private String rel;
 	private String path;
 	private boolean exported = true;
-	private final Map<String, ResourceMapping> resourceMappings = new HashMap<String, ResourceMapping>();
+	private final Map<String, ResourceMapping> resourceMappings = new HashMap<>();
 
 	public ResourceMapping() {}
 

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/config/ResourceMappingConfiguration.java

@@ -27,15 +27,10 @@
 @SuppressWarnings("deprecation")
 public class ResourceMappingConfiguration {
 
-	private final Map<Class<?>, ResourceMapping> resourceMappings = new HashMap<Class<?>, ResourceMapping>();
+	private final Map<Class<?>, ResourceMapping> resourceMappings = new HashMap<>();
 
 	public ResourceMapping setResourceMappingFor(Class<?> type) {
-		ResourceMapping rm = resourceMappings.get(type);
-		if (null == rm) {
-			rm = new ResourceMapping(type);
-			resourceMappings.put(type, rm);
-		}
-		return rm;
+		return resourceMappings.computeIfAbsent(type, value -> new ResourceMapping(type));
 	}
 
 	public ResourceMapping getResourceMappingFor(Class<?> type) {

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/event/AbstractRepositoryEventListener.java

@@ -48,14 +48,14 @@ public final void onApplicationEvent(RepositoryEvent event) {
 			onAfterCreate((T) event.getSource());
 		} else if (event instanceof AfterSaveEvent) {
 			onAfterSave((T) event.getSource());
-		} else if (event instanceof BeforeLinkSaveEvent) {
-			onBeforeLinkSave((T) event.getSource(), ((BeforeLinkSaveEvent) event).getLinked());
-		} else if (event instanceof AfterLinkSaveEvent) {
-			onAfterLinkSave((T) event.getSource(), ((AfterLinkSaveEvent) event).getLinked());
-		} else if (event instanceof BeforeLinkDeleteEvent) {
-			onBeforeLinkDelete((T) event.getSource(), ((BeforeLinkDeleteEvent) event).getLinked());
-		} else if (event instanceof AfterLinkDeleteEvent) {
-			onAfterLinkDelete((T) event.getSource(), ((AfterLinkDeleteEvent) event).getLinked());
+		} else if (event instanceof BeforeLinkSaveEvent beforeLinkSaveEvent) {
+			onBeforeLinkSave((T) event.getSource(), beforeLinkSaveEvent.getLinked());
+		} else if (event instanceof AfterLinkSaveEvent afterLinkSaveEvent) {
+			onAfterLinkSave((T) event.getSource(), afterLinkSaveEvent.getLinked());
+		} else if (event instanceof BeforeLinkDeleteEvent beforeLinkDeleteEvent) {
+			onBeforeLinkDelete((T) event.getSource(), beforeLinkDeleteEvent.getLinked());
+		} else if (event instanceof AfterLinkDeleteEvent afterLinkDeleteEvent) {
+			onAfterLinkDelete((T) event.getSource(), afterLinkDeleteEvent.getLinked());
 		} else if (event instanceof BeforeDeleteEvent) {
 			onBeforeDelete((T) event.getSource());
 		} else if (event instanceof AfterDeleteEvent) {

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/event/AnnotatedEventHandlerInvoker.java

@@ -51,7 +51,7 @@ public class AnnotatedEventHandlerInvoker implements ApplicationListener<Reposit
 	private static final Logger LOG = LoggerFactory.getLogger(AnnotatedEventHandlerInvoker.class);
 	private static final String PARAMETER_MISSING = "Invalid event handler method %s; At least a single argument is required to determine the domain type for which you are interested in events";
 
-	private final MultiValueMap<Class<? extends RepositoryEvent>, EventHandlerMethod> handlerMethods = new LinkedMultiValueMap<Class<? extends RepositoryEvent>, EventHandlerMethod>();
+	private final MultiValueMap<Class<? extends RepositoryEvent>, EventHandlerMethod> handlerMethods = new LinkedMultiValueMap<>();
 
 	@Override
 	public void onApplicationEvent(RepositoryEvent event) {
@@ -70,11 +70,11 @@ public void onApplicationEvent(RepositoryEvent event) {
 				continue;
 			}
 
-			List<Object> parameters = new ArrayList<Object>();
+			List<Object> parameters = new ArrayList<>();
 			parameters.add(src);
 
-			if (event instanceof LinkedEntityEvent) {
-				parameters.add(((LinkedEntityEvent) event).getLinked());
+			if (event instanceof LinkedEntityEvent linkedEntityEvent) {
+				parameters.add(linkedEntityEvent.getLinked());
 			}
 
 			if (LOG.isDebugEnabled()) {
@@ -149,7 +149,7 @@ private <T extends Annotation> void inspect(Object handler, Method method, Class
 		List<EventHandlerMethod> events = handlerMethods.get(eventType);
 
 		if (events == null) {
-			events = new ArrayList<EventHandlerMethod>();
+			events = new ArrayList<>();
 		}
 
 		if (events.isEmpty()) {

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/event/ValidatingRepositoryEventListener.java

@@ -57,7 +57,7 @@ public ValidatingRepositoryEventListener(ObjectFactory<PersistentEntities> persi
 		Assert.notNull(persistentEntitiesFactory, "PersistentEntities must not be null");
 
 		this.persistentEntitiesFactory = persistentEntitiesFactory;
-		this.validators = new LinkedMultiValueMap<String, Validator>();
+		this.validators = new LinkedMultiValueMap<>();
 	}
 
 	/**
@@ -69,7 +69,7 @@ public ValidatingRepositoryEventListener(ObjectFactory<PersistentEntities> persi
 	public ValidatingRepositoryEventListener setValidators(Map<String, Collection<Validator>> validators) {
 
 		for (Map.Entry<String, Collection<Validator>> entry : validators.entrySet()) {
-			this.validators.put(entry.getKey(), new ArrayList<Validator>(entry.getValue()));
+			this.validators.put(entry.getKey(), new ArrayList<>(entry.getValue()));
 		}
 
 		return this;
@@ -153,6 +153,6 @@ private Errors validate(String event, Object entity) {
 	private Collection<Validator> getValidatorsForEvent(String event) {
 
 		Collection<Validator> validators = this.validators.get(event);
-		return validators == null ? Collections.<Validator> emptySet() : validators;
+		return validators == null ? Collections.emptySet() : validators;
 	}
 }

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/ConfigurableHttpMethods.java

@@ -72,8 +72,8 @@ static ConfigurableHttpMethods of(HttpMethods methods) {
 
 		Assert.notNull(methods, "HttpMethods must not be null");
 
-		if (ConfigurableHttpMethods.class.isInstance(methods)) {
-			return ConfigurableHttpMethods.class.cast(methods);
+		if (methods instanceof ConfigurableHttpMethods configurableHttpMethods) {
+			return configurableHttpMethods;
 		}
 
 		return new ConfigurableHttpMethods(methods.stream().collect(Collectors.toSet()));

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/ConfigurationApplyingSupportedHttpMethodsAdapter.java

@@ -59,7 +59,7 @@ public HttpMethods getMethodsFor(PersistentProperty<?> property) {
 		HttpMethods methodsFor = delegate.getMethodsFor(property);
 		ResourceMapping mapping = resourceMetadata.getMappingFor(property);
 
-		if (!PropertyAwareResourceMapping.class.isInstance(mapping)) {
+		if (! (mapping instanceof PropertyAwareResourceMapping) ) {
 			return methodsFor;
 		}
 

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/CrudMethodsSupportedHttpMethods.java

@@ -60,7 +60,7 @@ public HttpMethods getMethodsFor(ResourceType resourceType) {
 
 		Assert.notNull(resourceType, "EntityRepresentationModel type must not be null");
 
-		Set<HttpMethod> methods = new HashSet<HttpMethod>();
+		Set<HttpMethod> methods = new HashSet<>();
 		methods.add(OPTIONS);
 
 		switch (resourceType) {
@@ -110,7 +110,7 @@ public HttpMethods getMethodsFor(PersistentProperty<?> property) {
 			return HttpMethods.none();
 		}
 
-		Set<HttpMethod> methods = new HashSet<HttpMethod>();
+		Set<HttpMethod> methods = new HashSet<>();
 
 		methods.add(GET);
 

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/ExposureConfiguration.java

@@ -149,7 +149,7 @@ HttpMethods filter(ConfigurableHttpMethods methods, PropertyAwareResourceMapping
 		return property.filter(mapping, methods);
 	}
 
-	private static <T> ComposableFilter<ResourceMetadata, ConfigurableHttpMethods> withTypeFilter(Class<?> type,
+	private static ComposableFilter<ResourceMetadata, ConfigurableHttpMethods> withTypeFilter(Class<?> type,
 			ComposableFilter<ResourceMetadata, ConfigurableHttpMethods> function) {
 
 		return (metadata, httpMethods) -> //

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/HttpMethods.java

@@ -64,6 +64,7 @@ public static HttpMethods of(Collection<HttpMethod> methods) {
 	 * 
 	 * @return
 	 */
+	@Override
 	default Set<HttpMethod> toSet() {
 		return stream().collect(StreamUtils.toUnmodifiableSet());
 	}
@@ -74,6 +75,7 @@ default Set<HttpMethod> toSet() {
 	 * @param method must not be {@literal null}.
 	 * @return
 	 */
+	@Override
 	default HttpMethods and(HttpMethod... method) {
 		return of(Stream.concat(stream(), Arrays.stream(method)).collect(Collectors.toSet()));
 	}

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/ParametersMetadata.java

@@ -49,7 +49,7 @@ public class ParametersMetadata implements Iterable<ParameterMetadata> {
 	 */
 	public List<String> getParameterNames() {
 
-		List<String> names = new ArrayList<String>(parameterMetadata.size());
+		List<String> names = new ArrayList<>(parameterMetadata.size());
 
 		for (ParameterMetadata metadata : parameterMetadata) {
 			names.add(metadata.getName());

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/RepositoryDetectionStrategy.java

@@ -47,7 +47,7 @@ public interface RepositoryDetectionStrategy {
 	 * @since 2.5
 	 * @soundtrack Katinka - Ausverkauf
 	 */
-	public static enum RepositoryDetectionStrategies implements RepositoryDetectionStrategy {
+	 enum RepositoryDetectionStrategies implements RepositoryDetectionStrategy {
 
 		/**
 		 * Considers all repositories.
@@ -84,7 +84,7 @@ public boolean isExported(RepositoryMetadata metadata) {
 			@Override
 			public boolean isExported(RepositoryMetadata metadata) {
 				return Modifier.isPublic(metadata.getRepositoryInterface().getModifiers());
-			};
+			}
 		},
 
 		/**

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/RepositoryMethodResourceMapping.java

@@ -90,7 +90,7 @@ public RepositoryMethodResourceMapping(Method method, ResourceMapping resourceMa
 
 	private static final List<ParameterMetadata> discoverParameterMetadata(Method method, String baseRel) {
 
-		List<ParameterMetadata> result = new ArrayList<ParameterMetadata>();
+		List<ParameterMetadata> result = new ArrayList<>();
 
 		for (MethodParameter parameter : new MethodParameters(method, PARAM_VALUE).getParameters()) {
 			if (!IMPLICIT_PARAMETER_TYPES.contains(parameter.getParameterType())

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/RepositoryResourceMappings.java

@@ -41,7 +41,7 @@ public class RepositoryResourceMappings extends PersistentEntitiesResourceMappin
 
 	private final Repositories repositories;
 	private final RepositoryRestConfiguration configuration;
-	private final Map<Class<?>, SearchResourceMappings> searchCache = new HashMap<Class<?>, SearchResourceMappings>();
+	private final Map<Class<?>, SearchResourceMappings> searchCache = new HashMap<>();
 
 	/**
 	 * Creates a new {@link RepositoryResourceMappings} from the given {@link RepositoryRestConfiguration},
@@ -103,7 +103,7 @@ public SearchResourceMappings getSearchResourceMappings(Class<?> domainType) {
 		}
 
 		RepositoryInformation repositoryInformation = repositories.getRequiredRepositoryInformation(domainType);
-		List<MethodResourceMapping> mappings = new ArrayList<MethodResourceMapping>();
+		List<MethodResourceMapping> mappings = new ArrayList<>();
 		ResourceMetadata resourceMapping = getMetadataFor(domainType);
 
 		if (resourceMapping.isExported()) {

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/SearchResourceMappings.java

@@ -51,7 +51,7 @@ public SearchResourceMappings(List<MethodResourceMapping> mappings) {
 
 		Assert.notNull(mappings, "MethodResourceMappings must not be null");
 
-		this.mappings = new HashMap<Path, MethodResourceMapping>(mappings.size());
+		this.mappings = new HashMap<>(mappings.size());
 
 		for (MethodResourceMapping mapping : mappings) {
 

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/TypeBasedCollectionResourceMapping.java

@@ -44,7 +44,8 @@ class TypeBasedCollectionResourceMapping implements CollectionResourceMapping {
 
 	private final Lazy<Path> path;
 	private final Lazy<LinkRelation> rel;
-	private final Lazy<ResourceDescription> description, itemResourceDescription;
+	private final Lazy<ResourceDescription> description;
+	private final Lazy<ResourceDescription> itemResourceDescription;
 
 	/**
 	 * Creates a new {@link TypeBasedCollectionResourceMapping} using the given type.

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/support/ResourceMappingUtils.java

@@ -44,10 +44,8 @@ protected ResourceMappingUtils() {}
 	public static String findRel(Class<?> type) {
 
 		RestResource anno = findAnnotation(type, RestResource.class);
-		if (anno != null) {
-			if (hasText(anno.rel())) {
+		if (anno != null && hasText(anno.rel())) {
 				return anno.rel();
-			}
 		}
 
 		return uncapitalize(type.getSimpleName().replaceAll("Repository", ""));
@@ -57,10 +55,8 @@ public static String findRel(Method method) {
 
 		RestResource anno = findAnnotation(method, RestResource.class);
 
-		if (anno != null) {
-			if (hasText(anno.rel())) {
+		if (anno != null && hasText(anno.rel()) ) {
 				return anno.rel();
-			}
 		}
 
 		return method.getName();
@@ -85,10 +81,8 @@ public static String findPath(Class<?> type) {
 
 		RestResource anno = findAnnotation(type, RestResource.class);
 
-		if (anno != null) {
-			if (hasTextExceptSlash(anno.path())) {
+		if (anno != null && hasTextExceptSlash(anno.path())) {
 				return removeLeadingSlash(anno.path());
-			}
 		}
 
 		return uncapitalize(type.getSimpleName().replaceAll("Repository", ""));
@@ -98,10 +92,8 @@ public static String findPath(Method method) {
 
 		RestResource anno = findAnnotation(method, RestResource.class);
 
-		if (anno != null) {
-			if (hasTextExceptSlash(anno.path())) {
+		if (anno != null && hasTextExceptSlash(anno.path())) {
 				return removeLeadingSlash(anno.path());
-			}
 		}
 
 		return method.getName();

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/support/ResourceStringUtils.java

@@ -20,7 +20,10 @@
  *
  * @author Florent Biville
  */
-public class ResourceStringUtils {
+public final class ResourceStringUtils {
+
+	private ResourceStringUtils(){
+	}
 
 	/**
 	 * Checks whether the given input contains actual text (slash excluded). This is a specializing variant of