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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 com.liferay.dynamic.data.mapping.expression.DDMExpression; import com.liferay.dynamic.data.mapping.expression.DDMExpressionException; import com.liferay.dynamic.data.mapping.expression.DDMExpressionFunction; import com.liferay.dynamic.data.mapping.expression.VariableDependencies; import com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionLexer; import com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser; import com.liferay.dynamic.data.mapping.expression.internal.parser.DDMExpressionParser.ExpressionContext; import com.liferay.dynamic.data.mapping.expression.model.Expression; import com.liferay.portal.kernel.util.ListUtil; import java.math.MathContext; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Set; import java.util.TreeMap; import org.antlr.v4.runtime.ANTLRInputStream; import org.antlr.v4.runtime.BailErrorStrategy; import org.antlr.v4.runtime.CharStream; import org.antlr.v4.runtime.CommonTokenStream; import org.antlr.v4.runtime.tree.ParseTreeWalker; /** * @author Miguel Angelo Caldas Gallindo * @author Marcellus Tavares */ public class DDMExpressionImpl<T> implements DDMExpression<T> { public DDMExpressionImpl(String expressionString, Class<T> expressionClass) throws DDMExpressionException { if ((expressionString == null) || expressionString.isEmpty()) { throw new IllegalArgumentException(); } _expressionString = expressionString; _expressionClass = expressionClass; _expressionContext = createExpressionContext(); registerExpressionFunctionsAndVariables(); registerExpressionModel(); } @Override public T evaluate() throws DDMExpressionException { Set<String> undefinedFunctionNames = getUndefinedFunctionNames(); if (!undefinedFunctionNames.isEmpty()) { throw new DDMExpressionException.FunctionNotDefined(undefinedFunctionNames); } try { DDMExpressionEvaluatorVisitor ddmExpressionEvaluatorVisitor = createDDMExpressionEvaluatorVisitor(); Object result = _expressionContext.accept(ddmExpressionEvaluatorVisitor); return (T) toRetunType(result); } catch (DDMExpressionException ddmee) { throw ddmee; } catch (Exception e) { throw new DDMExpressionException(e); } } @Override public Expression getModel() { return _expressionModel; } @Override public Map<String, VariableDependencies> getVariableDependenciesMap() throws DDMExpressionException { Map<String, VariableDependencies> variableDependenciesMap = new HashMap<>(); List<Variable> variables = ListUtil.fromCollection(_variables.values()); for (Variable variable : variables) { populateVariableDependenciesMap(variable, variableDependenciesMap); } return variableDependenciesMap; } @Override public void setBooleanVariableValue(String variableName, Boolean variableValue) { setVariableValue(variableName, variableValue); } @Override public void setDDMExpressionFunction(String functionName, DDMExpressionFunction ddmExpressionFunction) { _ddmExpressionFunctions.put(functionName, ddmExpressionFunction); } @Override public void setDoubleVariableValue(String variableName, Double variableValue) { setVariableValue(variableName, variableValue); } @Override public void setExpressionStringVariableValue(String variableName, String variableValue) { Variable variable = _variables.get(variableName); if (variable == null) { return; } variable.setExpressionString(variableValue); } @Override public void setFloatVariableValue(String variableName, Float variableValue) { setVariableValue(variableName, variableValue.doubleValue()); } @Override public void setIntegerVariableValue(String variableName, Integer variableValue) { setVariableValue(variableName, variableValue.doubleValue()); } @Override public void setLongVariableValue(String variableName, Long variableValue) { setVariableValue(variableName, variableValue.doubleValue()); } /** * @deprecated As of 2.1.0 */ @Deprecated @Override public void setMathContext(MathContext mathContext) { } @Override public void setNumberVariableValue(String variableName, Number variableValue) { setVariableValue(variableName, variableValue.doubleValue()); } @Override public void setObjectVariableValue(String variableName, Object variableValue) { Variable variable = _variables.get(variableName); if (variable == null) { return; } variable.setValue(variableValue); _variableValues.put(variableName, variableValue); } @Override public void setStringVariableValue(String variableName, String variableValue) throws DDMExpressionException { setVariableValue(variableName, variableValue); } protected void assertResultTypeClass(Class<?> expectedResultTypeClass, Class<?> resultTypeClass) throws DDMExpressionException { if (!expectedResultTypeClass.isAssignableFrom(resultTypeClass)) { throw new DDMExpressionException.IncompatipleReturnType(); } } protected DDMExpressionEvaluatorVisitor createDDMExpressionEvaluatorVisitor() throws DDMExpressionException { DDMExpressionEvaluatorVisitor ddmExpressionEvaluatorVisitor = new DDMExpressionEvaluatorVisitor(); // Functions ddmExpressionEvaluatorVisitor.addFunctions(_ddmExpressionFunctions); // Variables for (Map.Entry<String, Variable> entry : _variables.entrySet()) { ddmExpressionEvaluatorVisitor.addVariable(entry.getKey(), getVariableValue(entry.getValue())); } return ddmExpressionEvaluatorVisitor; } protected DDMExpression<Object> createExpression(String expressionString) throws DDMExpressionException { DDMExpressionImpl<Object> ddmExpression = new DDMExpressionImpl<>(expressionString, Object.class); for (String variableName : ddmExpression.getExpressionVariableNames()) { Variable variable = _variables.get(variableName); if (variable != null) { Object variableValue = getVariableValue(variable); ddmExpression.setVariableValue(variableName, variableValue); } } return ddmExpression; } protected DDMExpression<Object> createExpression(Variable variable) throws DDMExpressionException { if (variable.getExpressionString() == null) { return null; } DDMExpression<Object> ddmExpression = createExpression(variable.getExpressionString()); return ddmExpression; } protected ExpressionContext createExpressionContext() throws DDMExpressionException { try { CharStream charStream = new ANTLRInputStream(_expressionString); DDMExpressionLexer ddmExpressionLexer = new DDMExpressionLexer(charStream); DDMExpressionParser ddmExpressionParser = new DDMExpressionParser( new CommonTokenStream(ddmExpressionLexer)); ddmExpressionParser.setErrorHandler(new BailErrorStrategy()); return ddmExpressionParser.expression(); } catch (Exception e) { throw new DDMExpressionException.InvalidSyntax(e); } } protected Set<String> getExpressionFunctionNames() { return _expressionFunctionNames; } protected Set<String> getExpressionVariableNames() { return _variables.keySet(); } protected Set<String> getUndefinedFunctionNames() { Set<String> undefinedFunctionNames = new HashSet<>(getExpressionFunctionNames()); undefinedFunctionNames.removeAll(_ddmExpressionFunctions.keySet()); return undefinedFunctionNames; } protected Object getVariableValue(Variable variable) throws DDMExpressionException { Object variableValue = _variableValues.get(variable.getName()); if (variableValue != null) { return variableValue; } DDMExpression<Object> ddmExpression = createExpression(variable); variableValue = ddmExpression.evaluate(); _variableValues.put(variable.getName(), variableValue); return variableValue; } protected VariableDependencies populateVariableDependenciesMap(Variable variable, Map<String, VariableDependencies> variableDependenciesMap) throws DDMExpressionException { VariableDependencies variableDependencies = variableDependenciesMap.get(variable.getName()); if (variableDependencies != null) { return variableDependencies; } variableDependencies = new VariableDependencies(variable.getName()); if (variable.getExpressionString() != null) { DDMExpressionImpl<?> ddmExpression = new DDMExpressionImpl<>(variable.getExpressionString(), Object.class); for (String variableName : ddmExpression.getExpressionVariableNames()) { if (!_variables.containsKey(variableName)) { Variable newVariable = new Variable(variableName); _variables.put(variableName, newVariable); } VariableDependencies variableVariableDependencies = populateVariableDependenciesMap( _variables.get(variableName), variableDependenciesMap); variableVariableDependencies.addAffectedVariable(variableDependencies.getVariableName()); variableDependencies.addRequiredVariable(variableVariableDependencies.getVariableName()); } } variableDependenciesMap.put(variable.getName(), variableDependencies); return variableDependencies; } protected void registerExpressionFunctionsAndVariables() { ParseTreeWalker parseTreeWalker = new ParseTreeWalker(); DDMExpressionListener ddmExpressionListener = new DDMExpressionListener(); parseTreeWalker.walk(ddmExpressionListener, _expressionContext); // Function names _expressionFunctionNames.addAll(ddmExpressionListener.getFunctionNames()); // Variables for (String variableName : ddmExpressionListener.getVariableNames()) { _variables.put(variableName, new Variable(variableName)); } } protected void registerExpressionModel() { DDMExpressionModelVisitor ddmExpressionModelVisitor = new DDMExpressionModelVisitor(); _expressionModel = _expressionContext.accept(ddmExpressionModelVisitor); } protected void setVariableValue(String variableName, Object variableValue) { Variable variable = _variables.get(variableName); if (variable == null) { return; } variable.setValue(variableValue); _variableValues.put(variableName, variableValue); } protected double toDouble(Object result) throws DDMExpressionException { Number number = (Number) result; return number.doubleValue(); } protected float toFloat(Object result) throws DDMExpressionException { Number number = (Number) result; return number.floatValue(); } protected int toInteger(Object result) throws DDMExpressionException { Number number = (Number) result; return number.intValue(); } protected long toLong(Object result) throws DDMExpressionException { Number number = (Number) result; return number.longValue(); } protected Object toRetunType(Object result) throws DDMExpressionException { if (String.class.isAssignableFrom(_expressionClass)) { return String.valueOf(result); } else if (Boolean.class.isAssignableFrom(_expressionClass)) { assertResultTypeClass(Boolean.class, result.getClass()); return result; } else if (Double.class.isAssignableFrom(_expressionClass)) { assertResultTypeClass(Number.class, result.getClass()); return toDouble(result); } else if (Float.class.isAssignableFrom(_expressionClass)) { assertResultTypeClass(Number.class, result.getClass()); return toFloat(result); } else if (Integer.class.isAssignableFrom(_expressionClass)) { assertResultTypeClass(Number.class, result.getClass()); return toInteger(result); } else if (Long.class.isAssignableFrom(_expressionClass)) { assertResultTypeClass(Number.class, result.getClass()); return toLong(result); } else if (Number.class.isAssignableFrom(_expressionClass)) { assertResultTypeClass(Number.class, result.getClass()); return result; } return result; } private final Map<String, DDMExpressionFunction> _ddmExpressionFunctions = new HashMap<>(); private final Class<?> _expressionClass; private final ExpressionContext _expressionContext; private final Set<String> _expressionFunctionNames = new HashSet<>(); private Expression _expressionModel; private final String _expressionString; private final Map<String, Variable> _variables = new TreeMap<>(); private final Map<String, Object> _variableValues = new HashMap<>(); }