/* * #! * Ontopia Engine * #- * Copyright (C) 2001 - 2013 The Ontopia Project * #- * Licensed 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 net.ontopia.topicmaps.query.impl.rdbms; import java.util.List; import net.ontopia.persistence.query.jdo.JDOBoolean; import net.ontopia.persistence.query.jdo.JDOEquals; import net.ontopia.persistence.query.jdo.JDOField; import net.ontopia.persistence.query.jdo.JDONotEquals; import net.ontopia.persistence.query.jdo.JDONull; import net.ontopia.persistence.query.jdo.JDOObject; import net.ontopia.persistence.query.jdo.JDOValueIF; import net.ontopia.topicmaps.core.AssociationRoleIF; import net.ontopia.topicmaps.core.TopicIF; import net.ontopia.topicmaps.core.TopicMapIF; import net.ontopia.topicmaps.query.core.InvalidQueryException; /** * INTERNAL: Implements the 'role-player(role, player)' predicate. */ public class RolePlayerPredicate extends net.ontopia.topicmaps.query.impl.basic.RolePlayerPredicate implements JDOPredicateIF { public RolePlayerPredicate(TopicMapIF topicmap) { super(topicmap); } // --- JDOPredicateIF implementation public boolean isRecursive() { return false; } public void prescan(QueryBuilder builder, List arguments) { } public boolean buildQuery(QueryBuilder builder, List expressions, List arguments) throws InvalidQueryException { // Interpret arguments Object[] args = arguments.toArray(); if (args[0] instanceof AssociationRoleIF && args[1] instanceof TopicIF) { // Do direct predicate evaluation AssociationRoleIF role = (AssociationRoleIF)args[0]; if (args[1].equals(role.getPlayer())) expressions.add(JDOBoolean.TRUE); else expressions.add(JDOBoolean.FALSE); } else { JDOValueIF jv_role = builder.createJDOValue(args[0]); JDOValueIF jv_player = builder.createJDOValue(args[1]); // JDOQL: R.player = PLAYER expressions.add(new JDOEquals(new JDOField(jv_role, "player"), jv_player)); // if variable: filter out nulls if (jv_player.getType() == JDOValueIF.VARIABLE) expressions.add(new JDONotEquals(jv_player, new JDONull())); // JDOQL: R.topicmap = TOPICMAP expressions.add(new JDOEquals(new JDOField(jv_role, "topicmap"), new JDOObject(topicmap))); } return true; } }