/**************************************************************************************
* 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.view.stat;
import com.espertech.esper.epl.expression.ExprNode;
import com.espertech.esper.view.ViewFactory;
import com.espertech.esper.view.ViewParameterException;
import com.espertech.esper.view.*;
import com.espertech.esper.client.EventType;
import com.espertech.esper.epl.core.ViewResourceCallback;
import com.espertech.esper.epl.expression.ExprNode;
import com.espertech.esper.epl.expression.ExprNodeUtility;
import com.espertech.esper.core.StatementContext;
import com.espertech.esper.util.JavaClassHelper;
import java.util.List;
/**
* Factory for {@link RegressionLinestView} instances.
*/
public class RegressionLinestViewFactory implements ViewFactory
{
private List<ExprNode> viewParameters;
/**
* Expression X field.
*/
protected ExprNode expressionX;
/**
* Expression Y field.
*/
protected ExprNode expressionY;
protected StatViewAdditionalProps additionalProps;
protected EventType eventType;
public void setViewParameters(ViewFactoryContext viewFactoryContext, List<ExprNode> expressionParameters) throws ViewParameterException
{
this.viewParameters = expressionParameters;
}
public void attach(EventType parentEventType, StatementContext statementContext, ViewFactory optionalParentFactory, List<ViewFactory> parentViewFactories) throws ViewParameterException
{
ExprNode[] validated = ViewFactorySupport.validate("Correlation view", parentEventType, statementContext, viewParameters, false);
String errorMessage = "Regression view requires two expressions providing x and y values as properties";
if (validated.length < 2) {
throw new ViewParameterException(errorMessage);
}
if ((!JavaClassHelper.isNumeric(validated[0].getExprEvaluator().getType())) || (!JavaClassHelper.isNumeric(validated[1].getExprEvaluator().getType())))
{
throw new ViewParameterException(errorMessage);
}
expressionX = validated[0];
expressionY = validated[1];
additionalProps = StatViewAdditionalProps.make(validated, 2);
eventType = RegressionLinestView.createEventType(statementContext, additionalProps);
}
public boolean canProvideCapability(ViewCapability viewCapability)
{
return false;
}
public void setProvideCapability(ViewCapability viewCapability, ViewResourceCallback resourceCallback)
{
throw new UnsupportedOperationException("View capability " + viewCapability.getClass().getSimpleName() + " not supported");
}
public View makeView(StatementContext statementContext)
{
return new RegressionLinestView(statementContext, expressionX, expressionY, eventType, additionalProps);
}
public boolean canReuse(View view)
{
if (!(view instanceof RegressionLinestView))
{
return false;
}
if (additionalProps != null) {
return false;
}
RegressionLinestView myView = (RegressionLinestView) view;
if ((!ExprNodeUtility.deepEquals(myView.getExpressionX(), expressionX)) ||
(!ExprNodeUtility.deepEquals(myView.getExpressionY(), expressionY)))
{
return false;
}
return true;
}
public EventType getEventType()
{
return eventType;
}
}