/*
***************************************************************************************
* Copyright (C) 2006 EsperTech, Inc. All rights reserved. *
* http://www.espertech.com/esper *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
***************************************************************************************
*/
package com.espertech.esper.epl.parse;
import com.espertech.esper.collection.Pair;
import com.espertech.esper.epl.core.EngineImportService;
import com.espertech.esper.epl.expression.core.ExprValidationException;
import com.espertech.esper.epl.generated.EsperEPL2GrammarParser;
import com.espertech.esper.epl.spec.AnnotationDesc;
import com.espertech.esper.util.JavaClassHelper;
import java.util.ArrayList;
import java.util.List;
/**
* Walker to annotation stuctures.
*/
public class ASTAnnotationHelper {
/**
* Walk an annotation root name or child node (nested annotations).
*
* @param ctx annotation walk node
* @param engineImportService for engine imports
* @return annotation descriptor
* @throws ASTWalkException if the walk failed
*/
public static AnnotationDesc walk(EsperEPL2GrammarParser.AnnotationEnumContext ctx, EngineImportService engineImportService) throws ASTWalkException {
String name = ASTUtil.unescapeClassIdent(ctx.classIdentifier());
List<Pair<String, Object>> values = new ArrayList<Pair<String, Object>>();
if (ctx.elementValueEnum() != null) {
Object value = walkValue(ctx.elementValueEnum(), engineImportService);
values.add(new Pair<String, Object>("value", value));
} else if (ctx.elementValuePairsEnum() != null) {
walkValuePairs(ctx.elementValuePairsEnum(), values, engineImportService);
}
return new AnnotationDesc(name, values);
}
private static void walkValuePairs(EsperEPL2GrammarParser.ElementValuePairsEnumContext elementValuePairsEnumContext,
List<Pair<String, Object>> values,
EngineImportService engineImportService) {
for (EsperEPL2GrammarParser.ElementValuePairEnumContext ctx : elementValuePairsEnumContext.elementValuePairEnum()) {
Pair<String, Object> pair = walkValuePair(ctx, engineImportService);
values.add(pair);
}
}
private static Object walkValue(EsperEPL2GrammarParser.ElementValueEnumContext ctx, EngineImportService engineImportService) {
if (ctx.elementValueArrayEnum() != null) {
return walkArray(ctx.elementValueArrayEnum(), engineImportService);
}
if (ctx.annotationEnum() != null) {
return walk(ctx.annotationEnum(), engineImportService);
} else if (ctx.v != null) {
return ctx.v.getText();
} else if (ctx.classIdentifier() != null) {
return walkClassIdent(ctx.classIdentifier(), engineImportService);
} else {
return ASTConstantHelper.parse(ctx.constant());
}
}
private static Pair<String, Object> walkValuePair(EsperEPL2GrammarParser.ElementValuePairEnumContext ctx, EngineImportService engineImportService) {
String name = ctx.keywordAllowedIdent().getText();
Object value = walkValue(ctx.elementValueEnum(), engineImportService);
return new Pair<String, Object>(name, value);
}
private static Object walkClassIdent(EsperEPL2GrammarParser.ClassIdentifierContext ctx, EngineImportService engineImportService) {
String enumValueText = ctx.getText();
Object enumValue;
try {
enumValue = JavaClassHelper.resolveIdentAsEnumConst(enumValueText, engineImportService, true);
} catch (ExprValidationException e) {
throw ASTWalkException.from("Annotation value '" + enumValueText + "' is not recognized as an enumeration value, please check imports or use a primitive or string type");
}
if (enumValue != null) {
return enumValue;
}
throw ASTWalkException.from("Annotation enumeration value '" + enumValueText + "' not recognized as an enumeration class, please check imports or type used");
}
private static Object[] walkArray(EsperEPL2GrammarParser.ElementValueArrayEnumContext ctx, EngineImportService engineImportService) {
List<EsperEPL2GrammarParser.ElementValueEnumContext> elements = ctx.elementValueEnum();
Object[] values = new Object[elements.size()];
for (int i = 0; i < elements.size(); i++) {
values[i] = walkValue(elements.get(i), engineImportService);
}
return values;
}
}