As the compatibility fields (before 6.2.3) using transformer class to store data to JCR, each transformer has it own way to persist the data, hence the structure of JCR will be variant as well that will raise the complexity to relink function.

We should have behavior for this situation:

1. Cover all the Magnolia defined transformer for each field type
   • Pros: Could cover all the case of relink
   • Cons: Take time and effort, since the number of transformers is a lot.
2. Cover the default transformer of each field type only
   • Pros: Easy to maintain, less effort
   • Cons: Couldn't relink for field using transformer than default one

https://documentation.magnolia-cms.com/display/DOCS61/Transforming+field+values#4e1c0bf4617041a1b2e47437048097d9

Default transformer classes:

• For composite fields: info.magnolia.ui.form.field.transformer.composite.CompositeTransformer
• For switchable fields: info.magnolia.ui.form.field.transformer.composite.SwitchableTransformer

• For multivalue field: info.magnolia.ui.form.field.transformer.multi.MultiValueTransformer
• For multivalue composite field: info.magnolia.ui.form.field.transformer.multi.MultiValueSubChildrenNodePropertiesTransformer
  • for composite field: info.magnolia.ui.form.field.transformer.composite.NoOpCompositeTransformer

Other available transformer classes:

• info.magnolia.ui.form.field.transformer.composite.DelegatingCompositeFieldTransformer
• info.magnolia.ui.form.field.transformer.multi.DelegatingMultiValueFieldTransformer
• info.magnolia.ui.form.field.transformer.composite.NoOpCompositeTransformer
• info.magnolia.ui.form.field.transformer.multi.MultiValueJSONTransformer
• info.magnolia.ui.form.field.transformer.multi.MultiValueChildrenNodeTransformer
• info.magnolia.ui.form.field.transformer.multi.MultiValueChildNodeTransformer
• info.magnolia.ui.form.field.transformer.multi.MultiValueSubChildrenNodeTransformer

AC :

• support default transformers
• Field using transformers beyond the default one will be suppressed to relink