/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package com.datastax.sparql.gremlin; import org.apache.jena.graph.Triple; import org.apache.jena.sparql.algebra.op.OpBGP; import org.apache.jena.sparql.expr.E_Equals; import org.apache.jena.sparql.expr.E_Exists; import org.apache.jena.sparql.expr.E_GreaterThan; import org.apache.jena.sparql.expr.E_GreaterThanOrEqual; import org.apache.jena.sparql.expr.E_LessThan; import org.apache.jena.sparql.expr.E_LessThanOrEqual; import org.apache.jena.sparql.expr.E_LogicalAnd; import org.apache.jena.sparql.expr.E_LogicalOr; import org.apache.jena.sparql.expr.E_NotEquals; import org.apache.jena.sparql.expr.E_NotExists; import org.apache.jena.sparql.expr.Expr; import org.apache.tinkerpop.gremlin.process.traversal.P; import org.apache.tinkerpop.gremlin.process.traversal.Step; import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal; import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.__; import java.util.List; /** * @author Daniel Kuppitz (http://gremlin.guru) */ class WhereTraversalBuilder { public static GraphTraversal<?, ?> transform(final E_Equals expression) { final Object value = expression.getArg2().getConstant().getNode().getLiteralValue(); return __.as(expression.getArg1().getVarName()).is(P.eq(value)); } public static GraphTraversal<?, ?> transform(final E_NotEquals expression) { final Object value = expression.getArg2().getConstant().getNode().getLiteralValue(); return __.as(expression.getArg1().getVarName()).is(P.neq(value)); } public static GraphTraversal<?, ?> transform(final E_LessThan expression) { final Object value = expression.getArg2().getConstant().getNode().getLiteralValue(); return __.as(expression.getArg1().getVarName()).is(P.lt(value)); } public static GraphTraversal<?, ?> transform(final E_LessThanOrEqual expression) { final Object value = expression.getArg2().getConstant().getNode().getLiteralValue(); return __.as(expression.getArg1().getVarName()).is(P.lte(value)); } public static GraphTraversal<?, ?> transform(final E_GreaterThan expression) { final Object value = expression.getArg2().getConstant().getNode().getLiteralValue(); return __.as(expression.getArg1().getVarName()).is(P.gt(value)); } public static GraphTraversal<?, ?> transform(final E_GreaterThanOrEqual expression) { final Object value = expression.getArg2().getConstant().getNode().getLiteralValue(); return __.as(expression.getArg1().getVarName()).is(P.gte(value)); } public static GraphTraversal<?, ?> transform(final E_LogicalAnd expression) { return __.and( transform(expression.getArg1()), transform(expression.getArg2())); } public static GraphTraversal<?, ?> transform(final E_LogicalOr expression) { return __.or( transform(expression.getArg1()), transform(expression.getArg2())); } public static GraphTraversal<?, ?> transform(final E_Exists expression) { final OpBGP opBGP = (OpBGP) expression.getGraphPattern(); final List<Triple> triples = opBGP.getPattern().getList(); if (triples.size() != 1) throw new IllegalStateException("Unhandled EXISTS pattern"); final GraphTraversal<?, ?> traversal = TraversalBuilder.transform(triples.get(0)); final Step endStep = traversal.asAdmin().getEndStep(); final String label = (String) endStep.getLabels().iterator().next(); endStep.removeLabel(label); return traversal; } public static GraphTraversal<?, ?> transform(final E_NotExists expression) { final OpBGP opBGP = (OpBGP) expression.getGraphPattern(); final List<Triple> triples = opBGP.getPattern().getList(); if (triples.size() != 1) throw new IllegalStateException("Unhandled NOT EXISTS pattern"); final GraphTraversal<?, ?> traversal = TraversalBuilder.transform(triples.get(0)); final Step endStep = traversal.asAdmin().getEndStep(); final String label = (String) endStep.getLabels().iterator().next(); endStep.removeLabel(label); return __.not(traversal); } public static GraphTraversal<?, ?> transform(final Expr expression) { if (expression instanceof E_Equals) return transform((E_Equals) expression); if (expression instanceof E_NotEquals) return transform((E_NotEquals) expression); if (expression instanceof E_LessThan) return transform((E_LessThan) expression); if (expression instanceof E_LessThanOrEqual) return transform((E_LessThanOrEqual) expression); if (expression instanceof E_GreaterThan) return transform((E_GreaterThan) expression); if (expression instanceof E_GreaterThanOrEqual) return transform((E_GreaterThanOrEqual) expression); if (expression instanceof E_LogicalAnd) return transform((E_LogicalAnd) expression); if (expression instanceof E_LogicalOr) return transform((E_LogicalOr) expression); if (expression instanceof E_Exists) return transform((E_Exists) expression); if (expression instanceof E_NotExists) return transform((E_NotExists) expression); throw new IllegalStateException(String.format("Unhandled expression: %s", expression)); } }