Examples with BasicPattern org.apache.jena.sparql.core.BasicPattern used on opensource projects

Example 31 with BasicPattern

use of org.apache.jena.sparql.core.BasicPattern in project jena by apache.

the class OpTriple method equivalent.

public boolean equivalent(OpBGP opBGP) {
    BasicPattern bgp = opBGP.getPattern();
    if (bgp.size() != 1)
        return false;
    Triple t = bgp.get(0);
    return triple.equals(t);
}

Example 32 with BasicPattern

use of org.apache.jena.sparql.core.BasicPattern in project jena by apache.

the class TestFmtUtils method testFormatBGP_1.

@Test
public void testFormatBGP_1() {
    IndentedLineBuffer b = new IndentedLineBuffer();
    BasicPattern bgp = SSE.parseBGP("(prefix ((zz: <" + aUri + ">)) (bgp (zz:s zz:p zz:o)))");
    FmtUtils.formatPattern(b, bgp, getContext());
    assertEquals("zz:s zz:p zz:o .", b.toString());
}

Example 33 with BasicPattern

use of org.apache.jena.sparql.core.BasicPattern in project jena by apache.

the class TestFmtUtils method testFormatBGP_2.

@Test
public void testFormatBGP_2() {
    IndentedLineBuffer b = new IndentedLineBuffer();
    BasicPattern bgp = SSE.parseBGP("(prefix ((zz: <" + aUri + ">)) (bgp (zz:s zz:p zz:o) (zz:s zz:p 123) ))");
    FmtUtils.formatPattern(b, bgp, getContext());
    assertEquals("zz:s zz:p zz:o .\nzz:s zz:p 123 .", b.toString());
}

Example 34 with BasicPattern

use of org.apache.jena.sparql.core.BasicPattern in project jena by apache.

the class TestFmtUtils method formatPattern_2_triples.

@Test
public void formatPattern_2_triples() {
    BasicPattern basicPattern = new BasicPattern();
    basicPattern.add(getTriple());
    basicPattern.add(getTriple2());
    ByteArrayOutputStream os = new ByteArrayOutputStream();
    try (IndentedWriter iw = new IndentedWriter(os)) {
        SerializationContext sc = new SerializationContext();
        FmtUtils.formatPattern(iw, basicPattern, sc);
    }
    assertEquals("<n1> <n2> \"l3\" .\n" + "<nb1> <nb2> \"lb3\" .", new String(os.toByteArray()));
}

Example 35 with BasicPattern

use of org.apache.jena.sparql.core.BasicPattern in project jena by apache.

the class labelSearch method exec.

/* This be called once, with unevaluated arguments.
     * To do a rewrite of part of a query, we must use the fundamental PropertyFunction
     * interface to be called once with the input iterator.
     * Must not return null nor throw an exception.  Instead, return a QueryIterNullIterator
     * indicating no matches.  
     */
@Override
public QueryIterator exec(QueryIterator input, PropFuncArg argSubject, Node predicate, PropFuncArg argObject, ExecutionContext execCxt) {
    // No real need to check the pattern arguments because
    // the replacement triple pattern and regex will cope
    // but we illustrate testing here.
    Node nodeVar = argSubject.getArg();
    String pattern = NodeUtils.stringLiteral(argObject.getArg());
    if (pattern == null) {
        Log.warn(this, "Pattern must be a plain literal or xsd:string: " + argObject.getArg());
        return QueryIterNullIterator.create(execCxt);
    }
    if (false)
        // Old (ARQ 1) way - not recommended.
        return buildSyntax(input, nodeVar, pattern, execCxt);
    // Better 
    // Build a SPARQL algebra expression
    // Hidden variable
    Var var2 = createNewVar();
    BasicPattern bp = new BasicPattern();
    Triple t = new Triple(nodeVar, RDFS.label.asNode(), var2);
    bp.add(t);
    OpBGP op = new OpBGP(bp);
    Expr regex = new E_Regex(new ExprVar(var2.getName()), pattern, "i");
    Op filter = OpFilter.filter(regex, op);
    // ---- Evaluation
    if (true) {
        // Use the reference query engine
        // Create a table for the input stream (so it uses working memory at this point, 
        // which is why this is not the preferred way).  
        // Then join to expression for this stage.
        Table table = TableFactory.create(input);
        Op op2 = OpJoin.create(OpTable.create(table), filter);
        return Algebra.exec(op2, execCxt.getDataset());
    }
    // Use the default, optimizing query engine.
    return QC.execute(filter, input, execCxt);
}