Polishing.

Align assignability check for modifying execution.

See #4015

Author: mp911de

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

@@ -248,11 +248,11 @@ public ModifyingExecution(JpaQueryMethod method, EntityManager em) {
 
 			Class<?> returnType = method.getReturnType();
 
-			boolean isVoid = ClassUtils.isAssignable(returnType, Void.class);
-			boolean isInt = ClassUtils.isAssignable(returnType, Integer.class);
+			boolean isVoid = org.springframework.data.util.ReflectionUtils.isVoid(returnType);
+			boolean isNumber = ClassUtils.isAssignable(Number.class, returnType);
 
-			Assert.isTrue(isInt || isVoid,
-					"Modifying queries can only use void or int/Integer as return type; Offending method: " + method);
+			Assert.isTrue(isNumber || isVoid,
+					"Modifying queries can only use void, int/Integer, or long/Long as return type; Offending method: " + method);
 
 			this.em = em;
 			this.flush = method.getFlushAutomatically();

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

@@ -169,7 +169,7 @@ void allowsMethodReturnTypesForModifyingQuery() {
 	@Test
 	void modifyingExecutionRejectsNonIntegerOrVoidReturnType() {
 
-		when(method.getReturnType()).thenReturn((Class) Long.class);
+		when(method.getReturnType()).thenReturn((Class) String.class);
 		assertThatIllegalArgumentException().isThrownBy(() -> new ModifyingExecution(method, em));
 	}