net.sf.jasperreports.engine.fill.JRDistinctCountIncrementerFactory Maven / Gradle / Ivy
/*
* JasperReports - Free Java Reporting Library.
* Copyright (C) 2001 - 2009 Jaspersoft Corporation. All rights reserved.
* http://www.jaspersoft.com
*
* Unless you have purchased a commercial license agreement from Jaspersoft,
* the following license terms apply:
*
* This program is part of JasperReports.
*
* JasperReports is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* JasperReports is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with JasperReports. If not, see .
*/
package net.sf.jasperreports.engine.fill;
import java.util.HashSet;
import java.util.Set;
import net.sf.jasperreports.engine.type.ResetTypeEnum;
/**
* @author Teodor Danciu ([email protected])
* @version $Id: JRDistinctCountIncrementerFactory.java 3506 2010-03-04 14:48:54Z shertage $
*/
public class JRDistinctCountIncrementerFactory implements JRIncrementerFactory
{
/**
*
*/
private static JRDistinctCountIncrementerFactory mainInstance = new JRDistinctCountIncrementerFactory();
/**
*
*/
public JRDistinctCountIncrementerFactory()
{
}
/**
*
*/
public static JRDistinctCountIncrementerFactory getInstance()
{
return mainInstance;
}
/**
*
*/
public JRIncrementer getIncrementer(byte calculation)
{
return new JRDistinctCountIncrementer();
}
}
/**
*
*/
class JRDistinctCountIncrementer implements JRIncrementer
{
private DistinctCountHolder lastHolder = new DistinctCountHolder();
/**
*
*/
public JRDistinctCountIncrementer()
{
}
/**
*
*/
public Object increment(
JRFillVariable variable,
Object expressionValue,
AbstractValueProvider valueProvider
)
{
DistinctCountHolder holder = (DistinctCountHolder)variable.getIncrementedValue();
if (holder == null)
{
holder = lastHolder;
}
else
{
lastHolder = holder;
}
if (variable.getResetTypeValue() == ResetTypeEnum.REPORT || variable.isInitialized())
{
holder.addLastValue();
}
return new DistinctCountHolder(holder, expressionValue);
}
}
/**
*
*/
class DistinctCountHolder
{
private Set distinctValues = null;
private Object lastValue = null;
public DistinctCountHolder()
{
distinctValues = new HashSet();
}
public DistinctCountHolder(Set distinctValues)
{
this.distinctValues = distinctValues;
}
public DistinctCountHolder(DistinctCountHolder holder, Object lastValue)
{
this.distinctValues = holder.getDistinctValues();
this.lastValue = lastValue;
}
public void init()
{
distinctValues = new HashSet();
}
public Set getDistinctValues()
{
return distinctValues;
}
public Object getLastValue()
{
return lastValue;
}
public void addLastValue()
{
if (lastValue != null)
{
distinctValues.add(lastValue);
}
lastValue = null;
}
public long getCount()
{
return distinctValues.size() + (lastValue == null || distinctValues.contains(lastValue) ? 0 : 1);
}
}