Package com.datastax.astra.internal.serdes.collections

Interface DocumentMapper

Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public interface DocumentMapper
Functional interface for transforming documents during collection cloning. Allows custom transformation logic to be applied to each document as it's copied from the source collection to the target collection.

Example usage:


 // Add a timestamp to each document
 DocumentMapper addTimestamp = doc -> {
     doc.append("clonedAt", Instant.now());
     return doc;
 };
 
 // Remove sensitive fields
 DocumentMapper removeSensitive = doc -> {
     doc.remove("password");
     doc.remove("ssn");
     return doc;
 };
 
 // Transform field values
 DocumentMapper normalizeEmail = doc -> {
     if (doc.containsKey("email")) {
         doc.put("email", doc.getString("email").toLowerCase());
     }
     return doc;
 };
 
 CollectionCloneSettings settings = CollectionCloneSettings.builder()
     .documentMapper(addTimestamp)
     .build();

  • Method Summary

    Modifier and Type
    Method
    Description
    default DocumentMapper
    andThen(DocumentMapper after)
    Returns a mapper that applies this mapper followed by the after mapper.
    static DocumentMapper
    identity()
    Returns an identity mapper that returns the document unchanged.
    Document
    map(Document document)
    Transforms a document during the cloning process.

  • Method Details

    • map

      Document map(Document document)
      Transforms a document during the cloning process.
      Parameters:
      document - the source document to transform
      Returns:
      the transformed document to be inserted into the target collection

    • andThen

      default DocumentMapper andThen(DocumentMapper after)
      Returns a mapper that applies this mapper followed by the after mapper.
      Parameters:
      after - the mapper to apply after this mapper
      Returns:
      a composed mapper that applies both transformations in sequence

    • identity

      static DocumentMapper identity()
      Returns an identity mapper that returns the document unchanged.
      Returns:
      a mapper that performs no transformation