/*
* 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 <http://www.gnu.org/licenses/>.
*/
package net.sf.jasperreports.engine.util;
import java.math.BigDecimal;
import java.math.MathContext;
import java.math.RoundingMode;
/**
* {@link BigDecimalHandler} implementation used on Java 1.5 or newer.
*
* <p>
* This implementation uses a configured minimum precision when performing
* divisions.
*
* @author Lucian Chirita (lucianc@users.sourceforge.net)
* @version $Id: Java15BigDecimalHandler.java 3058 2009-09-19 08:19:49Z lucianc $
* @see BigDecimalUtils#divide(BigDecimal, BigDecimal)
* @see #PROPERTY_MINIMUM_PRECISION
*/
public class Java15BigDecimalHandler implements BigDecimalHandler
{
/**
* An integer property that provides the minimum precision to be used for
* division operations.
*
* <p>
* The property can only be set globally. The default value is 16.
*/
public static final String PROPERTY_MINIMUM_PRECISION =
JRProperties.PROPERTY_PREFIX + "big.decimal.minimum.precision";
private final int minPrecision;
private final ThreadLocal mathContexts;
public Java15BigDecimalHandler()
{
this(readConfiguredPrecision());
}
public Java15BigDecimalHandler(final int minPrecision)
{
if (minPrecision <= 0)
{
throw new IllegalArgumentException("minPrecision must be positive");
}
this.minPrecision = minPrecision;
this.mathContexts = new ThreadLocal();
}
private static int readConfiguredPrecision()
{
return JRProperties.getIntegerProperty(PROPERTY_MINIMUM_PRECISION);
}
/**
* Divides the values using the biggest of the dividend precision,
* the divisor precision and the configured minimum precision as result
* precision, and {@link RoundingMode#HALF_UP} as rounding mode.
*
* @see #PROPERTY_MINIMUM_PRECISION
*/
public BigDecimal divide(BigDecimal dividend, BigDecimal divisor)
{
int precision = getDivisionPrecision(dividend, divisor);
MathContext mathContext = getMathContext(precision);
return dividend.divide(divisor, mathContext);
}
protected int getDivisionPrecision(BigDecimal dividend, BigDecimal divisor)
{
int precision = minPrecision;
if (dividend.precision() > precision)
{
precision = dividend.precision();
}
if (divisor.precision() > precision)
{
precision = divisor.precision();
}
return precision;
}
protected MathContext getMathContext(int precision)
{
MathContext[] contexts = (MathContext[]) mathContexts.get();
int idx = precision - minPrecision;
if (contexts == null || contexts.length < idx + 1)
{
MathContext[] newContexts = new MathContext[idx + 1];
if (contexts != null)
{
System.arraycopy(contexts, 0, newContexts, 0, contexts.length);
}
mathContexts.set(newContexts);
contexts = newContexts;
}
MathContext mathContext = contexts[idx];
if (mathContext == null)
{
mathContext = new MathContext(precision, RoundingMode.HALF_UP);
contexts[idx] = mathContext;
}
return mathContext;
}
}