| /******************************************************************************* |
| * 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.sling.scripting.sightly.impl.compiler.optimization; |
| |
| import java.util.HashSet; |
| import java.util.Set; |
| |
| import org.apache.sling.scripting.sightly.compiler.expression.ExpressionNode; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.ArrayLiteral; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.BinaryOperation; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.BooleanConstant; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.Identifier; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.MapLiteral; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.NullLiteral; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.NumericConstant; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.PropertyAccess; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.RuntimeCall; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.StringConstant; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.TernaryOperator; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.UnaryOperation; |
| import org.apache.sling.scripting.sightly.compiler.expression.SideEffectVisitor; |
| |
| /** |
| * SideEffectVisitor which extracts all the variables from an expression. |
| */ |
| public class VariableFinder extends SideEffectVisitor { |
| |
| private final Set<String> variables; |
| |
| public VariableFinder(Set<String> variables) { |
| this.variables = variables; |
| } |
| |
| private void traverse(ExpressionNode node) { |
| if (node != null) { |
| node.accept(this); |
| } |
| } |
| |
| public static Set<String> findVariables(ExpressionNode node) { |
| HashSet<String> result = new HashSet<>(); |
| VariableFinder finder = new VariableFinder(result); |
| finder.traverse(node); |
| return result; |
| } |
| |
| @Override |
| public void visit(PropertyAccess propertyAccess) { |
| traverse(propertyAccess.getTarget()); |
| traverse(propertyAccess.getProperty()); |
| } |
| |
| @Override |
| public void visit(Identifier identifier) { |
| variables.add(identifier.getName()); |
| } |
| |
| @Override |
| public void visit(StringConstant text) { |
| } |
| |
| @Override |
| public void visit(BinaryOperation binaryOperation) { |
| traverse(binaryOperation.getLeftOperand()); |
| traverse(binaryOperation.getRightOperand()); |
| } |
| |
| @Override |
| public void visit(BooleanConstant booleanConstant) { |
| } |
| |
| @Override |
| public void visit(NumericConstant numericConstant) { |
| } |
| |
| @Override |
| public void visit(UnaryOperation unaryOperation) { |
| traverse(unaryOperation.getTarget()); |
| } |
| |
| @Override |
| public void visit(TernaryOperator ternaryOperator) { |
| traverse(ternaryOperator.getCondition()); |
| traverse(ternaryOperator.getThenBranch()); |
| traverse(ternaryOperator.getElseBranch()); |
| } |
| |
| @Override |
| public void visit(RuntimeCall runtimeCall) { |
| for (ExpressionNode node : runtimeCall.getArguments()) { |
| traverse(node); |
| } |
| } |
| |
| @Override |
| public void visit(MapLiteral mapLiteral) { |
| for (ExpressionNode value : mapLiteral.getMap().values()) { |
| traverse(value); |
| } |
| } |
| |
| @Override |
| public void visit(ArrayLiteral arrayLiteral) { |
| for (ExpressionNode item : arrayLiteral.getItems()) { |
| traverse(item); |
| } |
| } |
| |
| @Override |
| public void visit(NullLiteral nullLiteral) { |
| } |
| } |