graph://construct

Executes a SPARQL CONSTRUCT query against the RDFGraph in the exchange body to create new triples based on patterns matched in the existing data. This is useful for data transformation, restructuring, and ontology alignment tasks.

The resulting triples can either be merged into the existing graph (the default) or placed into a brand-new graph that replaces the exchange body — controlled by the newGraph parameter.

Parameters

Parameter	Type	Required	Default	Description
`query`	`String`	No*	—	Inline SPARQL CONSTRUCT query string.
`chimeraResource`	`ChimeraResourceBean`	No*	—	Resource pointing to a file containing the SPARQL CONSTRUCT query. See ChimeraResource.
`newGraph`	`boolean`	No	`false`	When `true`, the exchange body is replaced with a new in-memory graph containing only the constructed triples. When `false`, the constructed triples are added to the existing graph.
`namedGraph`	`String`	No	—	Named graph URI(s) where the constructed triples should be inserted. Multiple URIs can be separated by `;`.

*At least one of query or chimeraResource must be provided.

Example

Java DSLYAML

ChimeraResourceBean constructQuery = new ChimeraResourceBean(
    "file://./queries/transform.rq", "txt");
getCamelContext().getRegistry().bind("constructQuery", constructQuery);

from("direct:construct")
    .to("graph://construct?chimeraResource=#bean:constructQuery&newGraph=true");

- beans:
    - name: constructQuery
      type: com.cefriel.util.ChimeraResourceBean
      properties:
        url: "file://./queries/transform.rq"
        serializationFormat: "txt"

- route:
    from: "direct:construct"
    steps:
      - to:
          uri: "graph://construct"
          parameters:
            chimeraResource: "#constructQuery"
            newGraph: true