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/** * Copyright (c) 2000-present Liferay, Inc. All rights reserved. * * This library is free software; you can redistribute it and/or modify it under * the terms of the GNU Lesser General Public License as published by the Free * Software Foundation; either version 2.1 of the License, or (at your option) * any later version. * * This library is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more * details. */ package com.liferay.dynamic.data.mapping.expression.internal; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.AdditionExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.AndExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.BooleanParenthesisContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.DivisionExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.EqualsExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.ExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.FloatingPointLiteralContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.FunctionCallExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.FunctionParametersContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.GreaterThanExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.GreaterThanOrEqualsExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.IntegerLiteralContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.LessThanExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.LessThanOrEqualsExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.LogicalConstantContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.LogicalVariableContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.MinusExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.MultiplicationExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.NotEqualsExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.NotExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.NumericParenthesisContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.NumericVariableContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.OrExpressionContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.StringLiteralContext; import static com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.SubtractionExpressionContext; import com.liferay.dynamic.data.mapping.expression.DDMExpressionFunction; import com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionBaseVisitor; import com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser; import com.liferay.portal.kernel.util.StringUtil; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.antlr.v4.runtime.ParserRuleContext; import org.antlr.v4.runtime.Token; import org.antlr.v4.runtime.misc.NotNull; import org.antlr.v4.runtime.tree.ParseTree; /** * @author Marcellus Tavares */ public class DDMExpressionEvaluatorVisitor extends DDMExpressionBaseVisitor<Object> { public void addFunctions(Map<String, DDMExpressionFunction> ddmExpressionFunctions) { _functions.putAll(ddmExpressionFunctions); } public void addVariable(String name, Object value) { _variables.put(name, value); } @Override public Object visitAdditionExpression(@NotNull AdditionExpressionContext context) { Number l = visitChild(context, 0); Number r = visitChild(context, 2); return l.doubleValue() + r.doubleValue(); } @Override public Object visitAndExpression(@NotNull AndExpressionContext context) { boolean l = visitChild(context, 0); boolean r = visitChild(context, 2); return l && r; } @Override public Object visitBooleanParenthesis(@NotNull BooleanParenthesisContext context) { return visitChild(context, 1); } @Override public Object visitDivisionExpression(@NotNull DivisionExpressionContext context) { Number l = visitChild(context, 0); Number r = visitChild(context, 2); return l.doubleValue() / r.doubleValue(); } @Override public Object visitEqualsExpression(@NotNull EqualsExpressionContext context) { Object l = visitChild(context, 0); Object r = visitChild(context, 2); return l.equals(r); } @Override public Object visitExpression(@NotNull ExpressionContext context) { DDMExpressionParser.LogicalOrExpressionContext logicalOrExpressionContext = context.logicalOrExpression(); return logicalOrExpressionContext.accept(this); } @Override public Object visitFloatingPointLiteral(@NotNull FloatingPointLiteralContext context) { return Double.parseDouble(context.getText()); } @Override public Object visitFunctionCallExpression(@NotNull FunctionCallExpressionContext context) { String functionName = getFunctionName(context.functionName); DDMExpressionFunction ddmExpressionFunction = _functions.get(functionName); if (ddmExpressionFunction == null) { throw new IllegalStateException(String.format("Function \"%s\" not defined", functionName)); } Object[] params = getFunctionParameters(context.functionParameters()); return ddmExpressionFunction.evaluate(params); } @Override public Object visitGreaterThanExpression(@NotNull GreaterThanExpressionContext context) { Number l = visitChild(context, 0); Number r = visitChild(context, 2); return l.doubleValue() > r.doubleValue(); } @Override public Object visitGreaterThanOrEqualsExpression(@NotNull GreaterThanOrEqualsExpressionContext context) { Number l = visitChild(context, 0); Number r = visitChild(context, 2); return l.doubleValue() >= r.doubleValue(); } @Override public Object visitIntegerLiteral(@NotNull IntegerLiteralContext context) { Number number = Long.parseLong(context.getText()); return number.doubleValue(); } @Override public Object visitLessThanExpression(@NotNull LessThanExpressionContext context) { Number l = visitChild(context, 0); Number r = visitChild(context, 2); return l.doubleValue() < r.doubleValue(); } @Override public Object visitLessThanOrEqualsExpression(@NotNull LessThanOrEqualsExpressionContext context) { Number l = visitChild(context, 0); Number r = visitChild(context, 2); return l.doubleValue() <= r.doubleValue(); } @Override public Object visitLogicalConstant(@NotNull LogicalConstantContext context) { String boleanString = StringUtil.toLowerCase(context.getText()); return Boolean.parseBoolean(boleanString); } @Override public Object visitLogicalVariable(@NotNull LogicalVariableContext context) { String variable = context.getText(); Object variableValue = _variables.get(variable); if (variableValue == null) { throw new IllegalStateException(String.format("Variable \"%s\" not defined", variable)); } return variableValue; } @Override public Object visitMinusExpression(@NotNull MinusExpressionContext context) { Number number = visitChild(context, 1); return -(number.doubleValue()); } @Override public Object visitMultiplicationExpression(@NotNull MultiplicationExpressionContext context) { Number l = visitChild(context, 0); Number r = visitChild(context, 2); return l.doubleValue() * r.doubleValue(); } @Override public Object visitNotEqualsExpression(@NotNull NotEqualsExpressionContext context) { Object l = visitChild(context, 0); Object r = visitChild(context, 2); return !l.equals(r); } @Override public Object visitNotExpression(@NotNull NotExpressionContext context) { boolean b = visitChild(context, 1); return !b; } @Override public Object visitNumericParenthesis(@NotNull NumericParenthesisContext context) { return visitChild(context, 1); } @Override public Object visitNumericVariable(@NotNull NumericVariableContext context) { String variable = context.getText(); Object variableValue = _variables.get(variable); if (variableValue == null) { throw new IllegalStateException(String.format("variable %s not defined", variable)); } return variableValue; } @Override public Object visitOrExpression(@NotNull OrExpressionContext context) { boolean l = visitChild(context, 0); boolean r = visitChild(context, 2); return l || r; } @Override public Object visitStringLiteral(@NotNull StringLiteralContext context) { return StringUtil.unquote(context.getText()); } @Override public Object visitSubtractionExpression(@NotNull SubtractionExpressionContext context) { Number l = visitChild(context, 0); Number r = visitChild(context, 2); return l.doubleValue() - r.doubleValue(); } protected String getFunctionName(Token functionNameToken) { return functionNameToken.getText(); } protected Object[] getFunctionParameters(FunctionParametersContext context) { if (context == null) { return new Object[0]; } List parameters = new ArrayList<>(); for (int i = 0; i < context.getChildCount(); i += 2) { Object parameter = visitChild(context, i); parameters.add(parameter); } return parameters.toArray(new Object[parameters.size()]); } protected <T> T visitChild(ParserRuleContext parserRuleContext, int childIndex) { ParseTree parseTree = parserRuleContext.getChild(childIndex); return (T) parseTree.accept(this); } private final Map<String, DDMExpressionFunction> _functions = new HashMap<>(); private final Map<String, Object> _variables = new HashMap<>(); }