Package dev.morphia.aggregation.experimental.stages

Class Unwind

  • public class Unwind
extends Stage
    Deconstructs an array field from the input documents to output a document for each element. Each output document is the input document with the value of the array field replaced by the element.

    • Constructor Detail

      • Unwind

        protected Unwind()

    • Method Detail

      • on

        public static Unwind on​(String name)
        Creates a stage with the named array field
        Parameters:
        name - the array field
        Returns:
        this

      • getIncludeArrayIndex

        public String getIncludeArrayIndex()
        Returns:
        the value
        Developer note.
        This is an internal item. Its function and presence are subject to change without warning. Its use is highly discouraged.

      • getPath

        public Expression getPath()
        Returns:
        the value
        Developer note.
        This is an internal item. Its function and presence are subject to change without warning. Its use is highly discouraged.

      • getPreserveNullAndEmptyArrays

        public Boolean getPreserveNullAndEmptyArrays()
        Returns:
        the value
        Developer note.
        This is an internal item. Its function and presence are subject to change without warning. Its use is highly discouraged.

      • includeArrayIndex

        public Unwind includeArrayIndex​(String name)
        Optional. The name of a new field to hold the array index of the element. The name cannot start with a dollar sign $.
        Parameters:
        name - the new name
        Returns:
        this

      • optionsPresent

        public boolean optionsPresent()
        Returns:
        the value
        Developer note.
        This is an internal item. Its function and presence are subject to change without warning. Its use is highly discouraged.

      • preserveNullAndEmptyArrays

        public Unwind preserveNullAndEmptyArrays​(Boolean preserveNullAndEmptyArrays)
        Optional.
      • If true, if the path is null, missing, or an empty array, $unwind outputs the document.
      • If false, if path is null, missing, or an empty array, $unwind does not output a document.
Parameters:
preserveNullAndEmptyArrays - true to preserve
Returns:
this