| /********************************************************************* |
| * Copyright (c) 2008 The University of York. |
| * |
| * This program and the accompanying materials are made |
| * available under the terms of the Eclipse Public License 2.0 |
| * which is available at https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| **********************************************************************/ |
| package org.eclipse.epsilon.eol.dom; |
| |
| import java.util.Collection; |
| |
| import org.eclipse.epsilon.common.module.IModule; |
| import org.eclipse.epsilon.common.parse.AST; |
| import org.eclipse.epsilon.common.util.CollectionUtil; |
| import org.eclipse.epsilon.eol.compile.context.EolCompilationContext; |
| import org.eclipse.epsilon.eol.exceptions.EolRuntimeException; |
| import org.eclipse.epsilon.eol.execute.context.IEolContext; |
| import org.eclipse.epsilon.eol.types.EolAnyType; |
| import org.eclipse.epsilon.eol.types.EolCollectionType; |
| import org.eclipse.epsilon.eol.types.EolType; |
| |
| public class ItemSelectorExpression extends Expression { |
| |
| protected Expression targetExpression; |
| protected Expression indexExpression; |
| |
| @Override |
| public void build(AST cst, IModule module) { |
| super.build(cst, module); |
| targetExpression = (Expression) module.createAst(cst.getFirstChild(), module); |
| indexExpression = (Expression) module.createAst(cst.getSecondChild(), module); |
| } |
| |
| public Object execute(IEolContext context) throws EolRuntimeException { |
| |
| Object expression = context.getExecutorFactory().execute(targetExpression, context); |
| Object index = context.getExecutorFactory().execute(indexExpression, context); |
| |
| if ((expression instanceof Collection)) { |
| if (!(index instanceof Integer)) |
| throw new EolRuntimeException("Collection index must be an integer but " + index + " was provided instead.", indexExpression); |
| else return CollectionUtil.asList(expression).get((Integer)index); |
| } |
| //else if (expression instanceof EolMap){ |
| // return ((EolMap) expression).get(index); |
| //} |
| |
| throw new EolRuntimeException(expression + " is not a collection or a map.", targetExpression); |
| |
| } |
| |
| @Override |
| public void compile(EolCompilationContext context) { |
| targetExpression.compile(context); |
| indexExpression.compile(context); |
| |
| EolType targetExpressionType = targetExpression.getResolvedType(); |
| if (targetExpressionType != EolAnyType.Instance) { |
| if (targetExpressionType instanceof EolCollectionType) { |
| resolvedType = ((EolCollectionType) targetExpressionType).getContentType(); |
| } |
| else { |
| context.addErrorMarker(indexExpression, "[...] only applies to collections"); |
| } |
| } |
| |
| } |
| |
| } |