/*
* Copyright (c) 2003 The Visigoth Software Society. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Visigoth Software Society (http://www.visigoths.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. Neither the name "FreeMarker", "Visigoth", nor any of the names of the
* project contributors may be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "FreeMarker" or "Visigoth"
* nor may "FreeMarker" or "Visigoth" appear in their names
* without prior written permission of the Visigoth Software Society.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE VISIGOTH SOFTWARE SOCIETY OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Visigoth Software Society. For more
* information on the Visigoth Software Society, please see
* http://www.visigoths.org/
*/
package freemarker.core;
import java.io.IOException;
import java.text.NumberFormat;
import java.util.Locale;
import freemarker.template.*;
/**
* An instruction that outputs the value of a numerical expression.
* @author <a href="mailto:[email protected]">Jonathan Revusky</a>
*/
final class NumericalOutput extends TemplateElement {
private final Expression expression;
private final boolean hasFormat;
private final int minFracDigits;
private final int maxFracDigits;
private volatile FormatHolder formatCache; // creating new NumberFormat is slow operation
NumericalOutput(Expression expression) {
this.expression = expression;
hasFormat = false;
this.minFracDigits = 0;
this.maxFracDigits = 0;
}
NumericalOutput(Expression expression,
int minFracDigits,
int maxFracDigits)
{
this.expression = expression;
hasFormat = true;
this.minFracDigits = minFracDigits;
this.maxFracDigits = maxFracDigits;
}
void accept(Environment env) throws TemplateException, IOException
{
Number num = EvaluationUtil.getNumber(expression, env);
FormatHolder fmth = formatCache; // atomic sampling
if (fmth == null || !fmth.locale.equals(env.getLocale())) {
synchronized(this) {
fmth = formatCache;
if (fmth == null || !fmth.locale.equals(env.getLocale())) {
NumberFormat fmt = NumberFormat.getNumberInstance(env.getLocale());
if (hasFormat) {
fmt.setMinimumFractionDigits(minFracDigits);
fmt.setMaximumFractionDigits(maxFracDigits);
} else {
fmt.setMinimumFractionDigits(0);
fmt.setMaximumFractionDigits(50);
}
fmt.setGroupingUsed(false);
formatCache = new FormatHolder(fmt, env.getLocale());
fmth = formatCache;
}
}
}
// We must use Format even if hasFormat == false.
// Some locales may use non-Arabic digits, thus replacing the
// decimal separator in the result of toString() is not enough.
env.getOut().write(fmth.format.format(num));
}
public String getCanonicalForm() {
StringBuffer buf = new StringBuffer("#{");
buf.append(expression.getCanonicalForm());
if (hasFormat) {
buf.append(" ; ");
buf.append("m");
buf.append(minFracDigits);
buf.append("M");
buf.append(maxFracDigits);
}
buf.append("}");
return buf.toString();
}
public String getDescription() {
return getSource();
}
boolean heedsOpeningWhitespace() {
return true;
}
boolean heedsTrailingWhitespace() {
return true;
}
private static class FormatHolder {
final NumberFormat format;
final Locale locale;
FormatHolder(NumberFormat format, Locale locale) {
this.format = format;
this.locale = locale;
}
}
}
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