| /******************************************************************************* |
| * 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.plugin; |
| |
| import java.util.HashMap; |
| |
| import org.apache.sling.scripting.sightly.compiler.commands.OutText; |
| import org.apache.sling.scripting.sightly.impl.compiler.Syntax; |
| import org.apache.sling.scripting.sightly.compiler.expression.Expression; |
| import org.apache.sling.scripting.sightly.compiler.expression.ExpressionNode; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.BinaryOperation; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.BinaryOperator; |
| 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.NumericConstant; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.UnaryOperation; |
| import org.apache.sling.scripting.sightly.compiler.expression.nodes.UnaryOperator; |
| import org.apache.sling.scripting.sightly.impl.compiler.frontend.CompilerContext; |
| import org.apache.sling.scripting.sightly.compiler.commands.Conditional; |
| import org.apache.sling.scripting.sightly.compiler.commands.Loop; |
| import org.apache.sling.scripting.sightly.compiler.commands.VariableBinding; |
| import org.apache.sling.scripting.sightly.impl.compiler.PushStream; |
| |
| public class RepeatPlugin extends AbstractPlugin { |
| |
| private static final String INDEX = "index"; |
| private static final String COUNT = "count"; |
| private static final String FIRST = "first"; |
| private static final String MIDDLE = "middle"; |
| private static final String LAST = "last"; |
| private static final String ODD = "odd"; |
| private static final String EVEN = "even"; |
| private static final OutText NEW_LINE = new OutText("\n"); |
| |
| public RepeatPlugin() { |
| name = "repeat"; |
| priority = 130; |
| } |
| |
| @Override |
| public PluginInvoke invoke(final Expression expression, final PluginCallInfo callInfo, final CompilerContext compilerContext) { |
| return new DefaultPluginInvoke() { |
| |
| private String listVariable = compilerContext.generateVariable("collectionVar"); |
| private String collectionSizeVar = compilerContext.generateVariable("size"); |
| |
| @Override |
| public void beforeElement(PushStream stream, String tagName) { |
| stream.write(new VariableBinding.Start(listVariable, expression.getRoot())); |
| stream.write(new VariableBinding.Start(collectionSizeVar, |
| new UnaryOperation(UnaryOperator.LENGTH, new Identifier(listVariable)))); |
| stream.write(new Conditional.Start(collectionSizeVar, true)); |
| String itemVariable = decodeItemVariable(); |
| String loopStatusVar = Syntax.itemLoopStatusVariable(itemVariable); |
| String indexVariable = compilerContext.generateVariable("index"); |
| stream.write(new Loop.Start(listVariable, itemVariable, indexVariable)); |
| stream.write(new VariableBinding.Start(loopStatusVar, buildStatusObj(indexVariable, collectionSizeVar))); |
| |
| } |
| |
| @Override |
| public void afterTagClose(PushStream stream, boolean isSelfClosing) { |
| stream.write(NEW_LINE); |
| } |
| |
| @Override |
| public void afterElement(PushStream stream) { |
| stream.write(VariableBinding.END); |
| stream.write(Loop.END); |
| stream.write(Conditional.END); |
| stream.write(VariableBinding.END); |
| stream.write(VariableBinding.END); |
| } |
| |
| |
| private String decodeItemVariable() { |
| String[] args = callInfo.getArguments(); |
| if (args.length > 0) { |
| return args[0]; |
| } |
| return Syntax.DEFAULT_LIST_ITEM_VAR_NAME; |
| } |
| |
| private MapLiteral buildStatusObj(String indexVar, String sizeVar) { |
| HashMap<String, ExpressionNode> obj = new HashMap<>(); |
| Identifier indexId = new Identifier(indexVar); |
| BinaryOperation firstExpr = new BinaryOperation(BinaryOperator.EQ, indexId, NumericConstant.ZERO); |
| BinaryOperation lastExpr = new BinaryOperation( |
| BinaryOperator.EQ, |
| indexId, |
| new BinaryOperation(BinaryOperator.SUB, new Identifier(sizeVar), NumericConstant.ONE)); |
| obj.put(INDEX, indexId); |
| obj.put(COUNT, new BinaryOperation(BinaryOperator.ADD, indexId, NumericConstant.ONE)); |
| obj.put(FIRST, firstExpr); |
| obj.put(MIDDLE, new UnaryOperation( |
| UnaryOperator.NOT, |
| new BinaryOperation(BinaryOperator.OR, firstExpr, lastExpr))); |
| obj.put(LAST, lastExpr); |
| obj.put(ODD, parityCheck(indexId, NumericConstant.ZERO)); |
| obj.put(EVEN, parityCheck(indexId, NumericConstant.ONE)); |
| return new MapLiteral(obj); |
| } |
| |
| private ExpressionNode parityCheck(ExpressionNode numericExpression, NumericConstant expected) { |
| return new BinaryOperation( |
| BinaryOperator.EQ, |
| new BinaryOperation(BinaryOperator.REM, numericExpression, NumericConstant.TWO), |
| expected); |
| } |
| }; |
| } |
| } |