package com.espertech.esper.epl.expression;
import com.espertech.esper.client.EventBean;
import com.espertech.esper.epl.core.MethodResolutionService;
import com.espertech.esper.epl.enummethod.dot.ExprDotEvalTypeInfo;
import com.espertech.esper.util.JavaClassHelper;
import net.sf.cglib.reflect.FastClass;
import net.sf.cglib.reflect.FastMethod;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
public class ExprDotMethodEvalDuck implements ExprDotEval
{
private static final Log log = LogFactory.getLog(ExprDotMethodEvalDuck.class);
private final String statementName;
private final MethodResolutionService methodResolutionService;
private final String methodName;
private final Class[] parameterTypes;
private final ExprEvaluator[] parameters;
private Map<Class, FastMethod> cache;
public ExprDotMethodEvalDuck(String statementName, MethodResolutionService methodResolutionService, String methodName, Class[] parameterTypes, ExprEvaluator[] parameters)
{
this.statementName = statementName;
this.methodResolutionService = methodResolutionService;
this.methodName = methodName;
this.parameterTypes = parameterTypes;
this.parameters = parameters;
cache = new HashMap<Class, FastMethod>();
}
public Object evaluate(Object target, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext) {
if (target == null) {
return null;
}
FastMethod method;
if (cache.containsKey(target.getClass())) {
method = cache.get(target.getClass());
}
else {
method = getFastMethod(target.getClass());
cache.put(target.getClass(), method);
}
if (method == null) {
return null;
}
Object[] args = new Object[parameters.length];
for(int i = 0; i < args.length; i++)
{
args[i] = parameters[i].evaluate(eventsPerStream, isNewData, exprEvaluatorContext);
}
try
{
return method.invoke(target, args);
}
catch (InvocationTargetException e)
{
String message = JavaClassHelper.getMessageInvocationTarget(statementName, method.getJavaMethod(), target.getClass().getName(), args, e);
log.error(message, e.getTargetException());
}
return null;
}
private FastMethod getFastMethod(Class clazz)
{
try
{
Method method = methodResolutionService.resolveMethod(clazz, methodName, parameterTypes);
FastClass declaringClass = FastClass.create(Thread.currentThread().getContextClassLoader(), method.getDeclaringClass());
return declaringClass.getMethod(method);
}
catch(Exception e)
{
log.debug("Not resolved for class '" + clazz.getName() + "' method '" + methodName + "'");
}
return null;
}
public ExprDotEvalTypeInfo getTypeInfo() {
return ExprDotEvalTypeInfo.scalarOrUnderlying(Object.class);
}
}