ClassInfo#relationshipFields determines the field infos on each call

[torstenkuhnhenne]

When a relationship is mapped in OGM the method ClassInfo#relationshipFields is called every time. This is not necassary and the Collection<FieldInfo> can be determined once and cached. This is already done for the property fields.

The current implementation causes a not optimal performance:

With a cached implementation the method ClassInfo#relationshipFields tends to a zero execution time.

I will try to create a Pull Request that uses as same logic for the relationship fields that is currently in use for the property fields.

Expected Behavior

Cache the field infos for relationship property as for the property fields.

Current Behavior

Field infos for the relationship properties are determined for each mapping.

Context

We are using relationship properties in some of our domain classes and reading those from the database is not as optimal as it could be.

Your Environment

• Java version: 11
• Neo4j version (The version of the database): 3.5.22
• OGM Version (The version of this software): 3.2.17
• OGM Transport used (One of Bolt, HTTP or embedded): Bolt
• Neo4j Java Driver version (in case of Bolt transport): 4.1.1
• Link to your project: ./.

Steps to Reproduce

Use domain classes with @Relationship annotations and do some performance tests reading entities from the database.

[michael-simons]

Fixed with #850