HHH-19964 - Allow json serialization of Object valued attribute

Signed-off-by: Jan Schatteman <jschatte@redhat.com>

Author: jrenaat

hibernate-core/src/main/java/org/hibernate/type/format/AbstractJsonFormatMapper.java

@@ -18,7 +18,7 @@ public abstract class AbstractJsonFormatMapper implements FormatMapper {
 	@Override
 	public final <T> T fromString(CharSequence charSequence, JavaType<T> javaType, WrapperOptions wrapperOptions) {
 		final Type type = javaType.getJavaType();
-		if ( type == String.class || type == Object.class ) {
+		if ( type == String.class ) {
 			return (T) charSequence.toString();
 		}
 		return fromString( charSequence, type );
@@ -27,7 +27,7 @@ public final <T> T fromString(CharSequence charSequence, JavaType<T> javaType, W
 	@Override
 	public final <T> String toString(T value, JavaType<T> javaType, WrapperOptions wrapperOptions) {
 		final Type type = javaType.getJavaType();
-		if ( type == String.class || type == Object.class ) {
+		if ( value instanceof String ) {
 			return (String) value;
 		}
 		return toString( value, type );