Ensure sequential parameter binding numbering.

We now no longer allocate a parameter binding position for parameters that are represented with IS NULL or IS NOT NULL to ensure consistent parameter binding position numbering without gaps.

Closes #4171

Author: mp911de

spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/query/ParameterBinding.java

@@ -239,12 +239,16 @@ public PartTreeParameterBinding(BindingIdentifier identifier, ParameterOrigin or
 			this.templates = templates;
 			this.escape = escape;
 			this.value = value;
-			this.type = value == null
+			this.type = getType(part, value);
+			this.ignoreCase = Part.IgnoreCaseType.ALWAYS.equals(part.shouldIgnoreCase());
+			this.noWildcards = part.getProperty().getLeafProperty().isCollection();
+		}
+
+		static Type getType(Part part, @Nullable Object value) {
+			return value == null
 					&& (Type.SIMPLE_PROPERTY.equals(part.getType()) || Type.NEGATING_SIMPLE_PROPERTY.equals(part.getType()))
 							? Type.IS_NULL
 							: part.getType();
-			this.ignoreCase = Part.IgnoreCaseType.ALWAYS.equals(part.shouldIgnoreCase());
-			this.noWildcards = part.getProperty().getLeafProperty().isCollection();
 		}
 
 		/**

spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/query/ParameterMetadataProvider.java

@@ -214,12 +214,10 @@ private <T> PartTreeParameterBinding next(Part part, Class<T> type, Parameter pa
 		Class<T> reifiedType = Expression.class.equals(type) ? (Class<T>) Object.class : type;
 
 		Object value = bindableParameterValues == null ? PLACEHOLDER : bindableParameterValues.next();
+		Part.Type typeToUse = PartTreeParameterBinding.getType(part, value);
 		int currentPosition = ++position;
-		int currentBindMarker = ++bindMarker;
-
-		BindingIdentifier bindingIdentifier = parameter.getName().map(it -> BindingIdentifier.of(it, currentBindMarker))
-				.orElseGet(() -> BindingIdentifier.of(currentBindMarker));
 
+		BindingIdentifier bindingIdentifier = getBindingIdentifier(typeToUse, parameter);
 		BindingIdentifier origin = parameter.getName().map(it -> BindingIdentifier.of(it, currentPosition))
 				.orElseGet(() -> BindingIdentifier.of(currentPosition));
 
@@ -238,6 +236,17 @@ private <T> PartTreeParameterBinding next(Part part, Class<T> type, Parameter pa
 		return binding;
 	}
 
+	private BindingIdentifier getBindingIdentifier(Part.Type type, Parameter parameter) {
+
+		if (type == Part.Type.IS_NULL) {
+			return BindingIdentifier.of("null");
+		}
+
+		int currentBindMarker = ++bindMarker;
+		return parameter.getName().map(it -> BindingIdentifier.of(it, currentBindMarker))
+				.orElseGet(() -> BindingIdentifier.of(currentBindMarker));
+	}
+
 	/**
 	 * @return the scoring function if available {@link ScoringFunction#unspecified()} by default.
 	 * @since 4.0

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/JpaQueryCreatorTests.java

@@ -125,6 +125,18 @@ void negatingSimpleNullProperty() {
 				.validateQuery();
 	}
 
+	@Test // GH-4171
+	void simplePropertyAndNull() {
+
+		queryCreator(ORDER) //
+				.forTree(Order.class, "findByIdAndCompleted") //
+				.withParameterTypes(Long.class, Boolean.class).withParameters(null, false) //
+				.as(QueryCreatorTester::create) //
+				.expectJpql("SELECT o FROM %s o WHERE o.id IS NULL AND o.completed = ?1",
+						DefaultJpaEntityMetadata.unqualify(Order.class)) //
+				.validateQuery();
+	}
+
 	@Test // GH-3588
 	void simpleAnd() {
 
@@ -828,6 +840,12 @@ private JpaParametersParameterAccessor accessor(Class<?>... argumentTypes) {
 		return StubJpaParameterParameterAccessor.accessor(argumentTypes);
 	}
 
+	@Entity
+	class SampleEntity {
+		@Id Long id;
+		int isDeleted;
+	}
+
 	@jakarta.persistence.Entity
 	static class Order {
 

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/StubJpaParameterParameterAccessor.java

@@ -21,6 +21,7 @@
 import java.util.Arrays;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
 import org.mockito.Mockito;
 
 import org.springframework.core.MethodParameter;
@@ -49,13 +50,17 @@ static JpaParametersParameterAccessor accessor(Class<?>... parameterTypes) {
 
 	static AccessorBuilder accessorFor(Class<?>... parameterTypes) {
 		return arguments -> accessor(parameterTypes, arguments);
-
 	}
 
 	interface AccessorBuilder {
 		JpaParametersParameterAccessor withValues(Object... arguments);
 	}
 
+	@Override
+	public @Nullable Object getBindableValue(int index) {
+		return getValues()[index];
+	}
+
 	@SuppressWarnings({ "rawtypes", "unchecked" })
 	static JpaParametersParameterAccessor accessor(Class<?>[] parameterTypes, Object... parameters) {