| /* |
| * 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 org.apache.jena.sparql.expr; |
| |
| import org.apache.jena.sparql.engine.binding.Binding ; |
| import org.apache.jena.sparql.expr.nodevalue.XSDFuncOp ; |
| import org.apache.jena.sparql.function.FunctionEnv ; |
| import org.apache.jena.sparql.sse.Tags ; |
| |
| /* |
| Logical OR and AND is special with respect to handling errors truth table. |
| |
| A B | NOT A A && B A || B |
| ------------------------------------- |
| E E | E E E |
| E T | E E T |
| E F | E F E |
| T E | F E T |
| T T | F T T |
| T F | F F T |
| F E | T F E |
| F T | T F T |
| F F | T F F |
| */ |
| |
| public class E_LogicalOr extends ExprFunction2 |
| { |
| |
| private static final String functionName = Tags.tagOr ; |
| private static final String symbol = Tags.symOr ; |
| |
| public E_LogicalOr(Expr left, Expr right) |
| { |
| super(left, right, functionName, symbol) ; |
| } |
| |
| @Override |
| public NodeValue evalSpecial(Binding binding, FunctionEnv env) |
| { |
| ExprEvalException error = null ; |
| try { |
| NodeValue x = getArg1().eval(binding, env) ; |
| |
| if ( XSDFuncOp.booleanEffectiveValue(x) ) |
| return NodeValue.TRUE ; |
| } catch (ExprEvalException eee) |
| { |
| // RHS Must be true else error. |
| error = eee ; |
| } |
| |
| // LHS was false or error. |
| |
| try { |
| NodeValue y = getArg2().eval(binding, env) ; |
| |
| if ( XSDFuncOp.booleanEffectiveValue(y) ) |
| return NodeValue.TRUE ; |
| |
| // RHS is false but was there an error earlier? |
| if ( error != null ) |
| throw error ; |
| |
| return NodeValue.FALSE ; |
| } catch (ExprEvalException eee) |
| { |
| // LHS an error, RHS was not true => error |
| // Throw the first |
| if ( error != null ) |
| throw error ; |
| // RHS was false - throw this error. |
| throw eee ; |
| } |
| } |
| |
| @Override |
| public NodeValue eval(NodeValue x, NodeValue y) |
| { |
| // Evaluation only happens as part of copySubstitute. |
| // Proper evaluation is a special form as above. |
| |
| if ( ! x.isBoolean() ) |
| throw new ExprEvalException("Not a boolean: "+x) ; |
| if ( ! y.isBoolean() ) |
| throw new ExprEvalException("Not a boolean: "+y) ; |
| |
| boolean boolX = x.getBoolean() ; |
| boolean boolY = y.getBoolean() ; |
| return NodeValue.makeBoolean( boolX || boolY ) ; |
| } |
| |
| @Override |
| public Expr copy(Expr e1, Expr e2) { return new E_LogicalOr(e1 , e2 ) ; } |
| } |