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.epl.enummethod.eval; import com.espertech.esper.client.EventBean; import com.espertech.esper.epl.expression.ExprEvaluator; import com.espertech.esper.epl.expression.ExprEvaluatorContext; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.lang.reflect.Array; import java.util.Collection; import java.util.Iterator; public class EnumEvalSequenceEqual extends EnumEvalBase implements EnumEval { private static final Log log = LogFactory.getLog(EnumEvalSequenceEqual.class); public EnumEvalSequenceEqual(ExprEvaluator innerExpression, int streamCountIncoming) { super(innerExpression, streamCountIncoming); } public Object evaluateEnumMethod(EventBean[] eventsLambda, Collection target, boolean isNewData, ExprEvaluatorContext context) { Object otherObj = this.getInnerExpression().evaluate(eventsLambda, isNewData, context); if (otherObj == null) { return false; } if (!(otherObj instanceof Collection)) { if (otherObj.getClass().isArray()) { if (target.size() != Array.getLength(otherObj)) { return false; } if (target.isEmpty()) { return true; } Iterator oneit = target.iterator(); for (int i = 0; i < target.size(); i++) { Object first = oneit.next(); Object second = Array.get(otherObj, i); if (first == null) { if (second != null) { return false; } continue; } if (second == null) { return false; } if (!first.equals(second)) { return false; } } return true; } else { log.warn( "Enumeration method 'sequenceEqual' expected a Collection-type return value from its parameter but received '" + otherObj.getClass() + "'"); return false; } } Collection other = (Collection) otherObj; if (target.size() != other.size()) { return false; } if (target.isEmpty()) { return true; } Iterator oneit = target.iterator(); Iterator twoit = other.iterator(); for (int i = 0; i < target.size(); i++) { Object first = oneit.next(); Object second = twoit.next(); if (first == null) { if (second != null) { return false; } continue; } if (second == null) { return false; } if (!first.equals(second)) { return false; } } return true; } }