diff --git a/pljava-api/src/main/java/org/postgresql/pljava/annotation/processing/DDRProcessor.java b/pljava-api/src/main/java/org/postgresql/pljava/annotation/processing/DDRProcessor.java
index 2a0b155ab..a2f9fcd44 100644
--- a/pljava-api/src/main/java/org/postgresql/pljava/annotation/processing/DDRProcessor.java
+++ b/pljava-api/src/main/java/org/postgresql/pljava/annotation/processing/DDRProcessor.java
@@ -3681,7 +3681,7 @@ else if ( ! funcName.equals(fn)  &&  ! isSynthetic )
 				long explicit =
 					Arrays.stream(operands).filter(Objects::nonNull).count();
 
-				if ( 0 != explicit  &&  ! isSynthetic )
+				if ( 0 != explicit  &&  isSynthetic )
 				{
 					msg(Kind.ERROR, m_targetElement, m_origin,
 						"@Operator with synthetic= must not specify " +
@@ -4442,7 +4442,7 @@ else if ( null == _plan.stateType )
 									.skip(1) // skip the state argument
 									.map(pi ->
 										(Map.Entry<Identifier.Simple, DBType>)
-										new AbstractMap.SimpleImmutableEntry(
+										new AbstractMap.SimpleImmutableEntry<>(
 											Identifier.Simple.fromJava(
 												pi.name()
 											),
diff --git a/pljava-examples/src/main/java/org/postgresql/pljava/example/annotation/ComplexScalar.java b/pljava-examples/src/main/java/org/postgresql/pljava/example/annotation/ComplexScalar.java
index d664e0145..064bbea62 100644
--- a/pljava-examples/src/main/java/org/postgresql/pljava/example/annotation/ComplexScalar.java
+++ b/pljava-examples/src/main/java/org/postgresql/pljava/example/annotation/ComplexScalar.java
@@ -98,9 +98,16 @@ public class ComplexScalar implements SQLData {
 
 	/**
 	 * Return the same 'complex' passed in, logging its contents at level INFO.
+	 *<p>
+	 * Also create an unnecessary {@code <<} operator for this, with an equally
+	 * unnecessary explicit operand type, simply as a regression test
+	 * of issue #330.
 	 * @param cpl any instance of this UDT
 	 * @return the same instance passed in
 	 */
+	@Operator(
+		name = "javatest.<<", right = "javatest.complex"
+	)
 	@Function(
 		schema="javatest", name="logcomplex", effects=IMMUTABLE,
 		onNullInput=RETURNS_NULL)