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.ExprValidationException;
import com.espertech.esper.epl.generated.EsperEPL2Ast;
import com.espertech.esper.epl.spec.AnnotationDesc;
import com.espertech.esper.util.JavaClassHelper;
import org.antlr.runtime.tree.Tree;
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 node annotation walk node
* @param engineImportService for engine imports
* @return annotation descriptor
* @throws ASTWalkException if the walk failed
*/
public static AnnotationDesc walk(Tree node, EngineImportService engineImportService) throws ASTWalkException
{
String name = node.getChild(0).getText();
List<Pair<String, Object>> values = new ArrayList<Pair<String, Object>>();
Object value;
for (int i = 1; i < node.getChildCount(); i++)
{
if (node.getChild(i).getType() == EsperEPL2Ast.ANNOTATION_VALUE)
{
Pair<String, Object> entry = walkValuePair(node.getChild(i), engineImportService);
values.add(new Pair<String, Object>(entry.getFirst(), entry.getSecond()));
}
else if (node.getChild(i).getType() == EsperEPL2Ast.CLASS_IDENT)
{
Object enumValue = walkClassIdent(node.getChild(i), engineImportService);
values.add(new Pair<String, Object>("value", enumValue));
}
else
{
value = walkValue(node.getChild(i));
values.add(new Pair<String, Object>("value", value));
}
}
return new AnnotationDesc(name, values);
}
private static Object walkValue(Tree child)
{
return ASTConstantHelper.parse(child);
}
private static Pair<String, Object> walkValuePair(Tree node, EngineImportService engineImportService)
{
String name = node.getChild(0).getText();
if (node.getChild(1).getType() == EsperEPL2Ast.ANNOTATION_ARRAY)
{
Object[] values = walkArray(node.getChild(1));
return new Pair<String, Object>(name, values);
}
if (node.getChild(1).getType() == EsperEPL2Ast.ANNOTATION)
{
AnnotationDesc anno = walk(node.getChild(1), engineImportService);
return new Pair<String, Object>(name, anno);
}
else if (node.getChild(1).getType() == EsperEPL2Ast.CLASS_IDENT)
{
Object enumValue = walkClassIdent(node.getChild(1), engineImportService);
return new Pair<String, Object>(name, enumValue);
}
else
{
Object constant = ASTConstantHelper.parse(node.getChild(1));
return new Pair<String, Object>(name, constant);
}
}
private static Object walkClassIdent(Tree child, EngineImportService engineImportService)
{
String enumValueText = child.getText();
Object enumValue;
try
{
enumValue = JavaClassHelper.resolveIdentAsEnumConst(enumValueText, null, engineImportService);
}
catch (ExprValidationException e)
{
throw new ASTWalkException("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 new ASTWalkException("Annotation enumeration value '" + enumValueText + "' not recognized as an enumeration class, please check imports or type used");
}
private static Object[] walkArray(Tree node)
{
Object[] values = new Object[node.getChildCount()];
for (int i = 0; i < node.getChildCount(); i++)
{
values[i] = walkValue(node.getChild(i));
}
return values;
}
}