DatasetTDB2 with separate namedGraphs

[Laura Morales]

Can somebody please help me with configuring an assembler file for DatasetTDB2 
with multiple namedGraphs in separate files? I have this configuration but it 
doesn't work

======================================================================
PREFIX fuseki:  <http://jena.apache.org/fuseki#>
PREFIX ja:      <http://jena.hpl.hp.com/2005/11/Assembler#>
PREFIX rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs:    <http://www.w3.org/2000/01/rdf-schema#>
PREFIX tdb:     <http://jena.hpl.hp.com/2008/tdb#>
PREFIX tdb2:    <http://jena.apache.org/2016/tdb#>
PREFIX text:    <http://jena.apache.org/text#>

:dataset a ja:RDFDataset .

:dataset ja:namedGraph
[
    ja:graphName <http://example.org/graph1> ;
    ja:graph
    [
        a tdb2:GraphTDB2 ;
        tdb2:location "/path/to/dataset1/" ;
    ]
] .

:dataset ja:namedGraph
[
    ja:graphName <http://example.org/graph2> ;
    ja:graph
    [
        a tdb2:GraphTDB2 ;
        tdb2:location "/path/to/dataset2/" ;
    ]
] .
======================================================================

I get this error when I try to query it:

org.apache.jena.sparql.ARQException: No such type: 
<http://jena.apache.org/2016/tdb#DatasetTDB2>
        at 
org.apache.jena.sparql.core.assembler.AssemblerUtils.build(AssemblerUtils.java:122)
        at tdb2.cmdline.ModTDBDataset.createDataset(ModTDBDataset.java:82)
        at arq.cmdline.ModDataset.getDataset(ModDataset.java:36)
        at arq.query.getDataset(query.java:176)
        at arq.query.queryExec(query.java:213)
        at arq.query.exec(query.java:153)
        at jena.cmd.CmdMain.mainMethod(CmdMain.java:93)
        at jena.cmd.CmdMain.mainRun(CmdMain.java:58)
        at jena.cmd.CmdMain.mainRun(CmdMain.java:45)
        at tdb2.tdbquery.main(tdbquery.java:30)