Package org.gcube.informationsystem.types.reference.properties

Interface TypeProjection

  • All Superinterfaces:
    Element, PropertyElement, Serializable
    All Known Implementing Classes:
    TypeProjectionImpl
    @TypeMetadata(name="TypeProjection",
              description="The type used to store a Type\'s instance-list projection.",
              version="1.0.0")
@Change(version="1.0.0",
        description="First Version")
public interface TypeProjection
extends PropertyElement
    A curated or auto-generated field-selection query, attached to a Type, used to shape the list view of that Type's instances. Unlike a Query Template, a TypeProjection is unparameterized (no variables) and has no independent identity of its own — it is always reached through the Type it belongs to, never addressed on its own.

    Named TypeProjection, not the bare Projection: the latter already denotes, generically, the response shape any _emit-bearing query produces (see appendix/07-json-query-syntax-reference.md's "Response Projection (`_emit`)"), so it would collide with that pre-existing usage. This type is one specific, canonical, always-present projection rule attached to a Type — not any arbitrary `_emit`-shaped query result.

    Deliberately extends PropertyElement, not IdentifiableElement: a TypeProjection has no id of its own (it is never addressed by one), but still carries metadata, declared directly here rather than inherited.

    Author:
    Luca Frosini (ISTI - CNR)

    • Method Detail

      • getMetadata

        @ISProperty(name="metadata",
            description="Who generated or last changed this projection, and when.",
            readonly=true,
            mandatory=true)
Metadata getMetadata()
        Returns the metadata associated with this projection (who generated or last changed it, and when). Declared directly here, not inherited from IdentifiableElement, since a TypeProjection has no id of its own.
        Returns:
        the metadata

      • setMetadata

        void setMetadata​(Metadata metadata)
        Sets the metadata associated with this projection.
        Parameters:
        metadata - the metadata

      • getQueryAsString

        @ISProperty(name="query",
            description="The QBE (Query By Example) query defining this projection. Unlike a Query Template, it is unparameterized: it never contains variables.",
            readonly=false,
            mandatory=true)
String getQueryAsString()
                 throws org.gcube.com.fasterxml.jackson.core.JsonProcessingException
        Returns the query body as a string.
        Returns:
        the query as a string
        Throws:
        org.gcube.com.fasterxml.jackson.core.JsonProcessingException - if an error occurs during serialization

      • setQuery

        void setQuery​(String query)
       throws org.gcube.com.fasterxml.jackson.core.JsonProcessingException,
              IOException
        Sets the query body from a string.
        Parameters:
        query - the query as a string
        Throws:
        IOException - if an error occurs during parsing
        org.gcube.com.fasterxml.jackson.core.JsonProcessingException - if an error occurs during JSON processing

      • setQuery

        void setQuery​(org.gcube.com.fasterxml.jackson.databind.JsonNode query)
        Sets the query body from a JsonNode.

        Deliberately typed as JsonNode, not a polymorphic Element reference — the query's content embeds its own "type" (e.g. "EService"), which describes what it queries, not a real instance to deserialize. Typing it as a plain JsonNode keeps Element's @JsonTypeInfo-driven polymorphic resolution from being triggered on that embedded discriminator — the exact same reason QueryTemplate.setTemplate(JsonNode) is typed the same way.

        Parameters:
        query - the query as a JsonNode

      • getQuery

        org.gcube.com.fasterxml.jackson.databind.JsonNode getQuery()
        Returns the query body as a JsonNode.
        Returns:
        the query as a JsonNode

      • getDescription

        @ISProperty(name="description",
            description="Which fields/columns this projection returns, and why.",
            readonly=false,
            mandatory=true)
String getDescription()
        Returns the description of this projection — which fields/columns it returns and why.
        Returns:
        the description

      • setDescription

        void setDescription​(String description)
        Sets the description of this projection.
        Parameters:
        description - the description

      • setSource

        void setSource​(TypeProjection.Source source)
        Sets the source of this projection.
        Parameters:
        source - the source