Java tutorial
/* * ************************************************************************************* * Copyright (C) 2008 EsperTech, Inc. All rights reserved. * * http://esper.codehaus.org * * 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.core.context.mgr; import com.espertech.esper.client.EventBean; import com.espertech.esper.client.EventPropertyGetter; import com.espertech.esper.client.EventType; import com.espertech.esper.client.PropertyAccessException; import com.espertech.esper.collection.Pair; import com.espertech.esper.epl.core.EngineImportSingleRowDesc; import com.espertech.esper.epl.core.MethodResolutionService; import com.espertech.esper.epl.expression.*; import com.espertech.esper.event.EventAdapterService; import com.espertech.esper.util.JavaClassHelper; 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.util.List; public class ContextControllerHashedGetterSingleRow implements EventPropertyGetter { private static final Log log = LogFactory.getLog(ContextControllerHashedGetterSingleRow.class); private final String statementName; private final FastMethod fastMethod; private final ExprEvaluator[] evaluators; private final int granularity; public ContextControllerHashedGetterSingleRow(String statementName, String functionName, Pair<Class, EngineImportSingleRowDesc> func, List<ExprNode> parameters, int granularity, MethodResolutionService methodResolutionService, EventType eventType, EventAdapterService eventAdapterService, String statementId) throws ExprValidationException { ExprNodeUtilMethodDesc staticMethodDesc = ExprNodeUtility.resolveMethodAllowWildcardAndStream( func.getFirst().getName(), null, func.getSecond().getMethodName(), parameters, methodResolutionService, eventAdapterService, statementId, true, eventType, new ExprNodeUtilResolveExceptionHandlerDefault(func.getSecond().getMethodName(), true), func.getSecond().getMethodName()); this.statementName = statementName; this.evaluators = staticMethodDesc.getChildEvals(); this.granularity = granularity; this.fastMethod = staticMethodDesc.getFastMethod(); } public Object get(EventBean eventBean) throws PropertyAccessException { EventBean[] events = new EventBean[] { eventBean }; Object[] parameters = new Object[evaluators.length]; for (int i = 0; i < evaluators.length; i++) { parameters[i] = evaluators[i].evaluate(events, true, null); } try { Object result = fastMethod.invoke(null, parameters); if (result == null) { return 0; } int value = ((Number) result).intValue(); if (value >= 0) { return value % granularity; } return -value % granularity; } catch (InvocationTargetException e) { String message = JavaClassHelper.getMessageInvocationTarget(statementName, fastMethod.getJavaMethod(), fastMethod.getDeclaringClass().getName(), parameters, e); log.error(message, e.getTargetException()); } return 0; } public boolean isExistsProperty(EventBean eventBean) { return false; } public Object getFragment(EventBean eventBean) throws PropertyAccessException { return null; } }