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Super CSV is a fast, programmer-friendly, free CSV package for Java
/*
* Copyright 2007 Kasper B. Graversen
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.supercsv.cellprocessor;
import java.text.DecimalFormat;
import org.supercsv.cellprocessor.ift.DoubleCellProcessor;
import org.supercsv.cellprocessor.ift.LongCellProcessor;
import org.supercsv.cellprocessor.ift.StringCellProcessor;
import org.supercsv.exception.SuperCsvCellProcessorException;
import org.supercsv.util.CsvContext;
/**
* Converts a double into a formatted string using the {@link DecimalFormat} class and the default locale. This is
* useful, when you need to show numbers with a specific number of digits.
*
* Please be aware that the constructors that use DecimalFormat are not thread-safe, so it is generally better
* to use the constructors that accept a date format String.
*
* In the format string, the following characters are defined as :
*
*
* 0 - means Digit
* # - means Digit, zero shows as absent (works only as zero padding on the right hand side of the number)
* . - means Decimal separator or monetary decimal separator
* - - means Minus sign
* , - means Grouping separator
*
*
*
* If you want to convert from a String to a decimal, use the {@link ParseDouble} or {@link ParseBigDecimal} processor.
*
* @since 1.50
* @author Kasper B. Graversen
* @author James Bassett
*/
public class FmtNumber extends CellProcessorAdaptor implements DoubleCellProcessor, LongCellProcessor {
/** the decimal format string */
private final String decimalFormat;
/** the decimal format object - not thread safe */
private final DecimalFormat formatter;
/**
* Constructs a new FmtNumber processor, which converts a double into a formatted string using the supplied
* decimal format String. This constructor is thread-safe.
*
* @param decimalFormat
* the decimal format String (see {@link DecimalFormat})
* @throws NullPointerException
* if decimalFormat is null
*/
public FmtNumber(final String decimalFormat) {
super();
checkPreconditions(decimalFormat);
this.decimalFormat = decimalFormat;
this.formatter = null;
}
/**
* Constructs a new FmtNumber processor, which converts a double into a formatted string using the supplied
* decimal format String, then calls the next processor in the chain. This constructor is thread-safe.
*
* @param decimalFormat
* the decimal format String (see {@link DecimalFormat})
* @param next
* the next processor in the chain
* @throws NullPointerException
* if decimalFormat or next is null
*/
public FmtNumber(final String decimalFormat, final StringCellProcessor next) {
super(next);
checkPreconditions(decimalFormat);
this.decimalFormat = decimalFormat;
this.formatter = null;
}
/**
* Constructs a new FmtNumber processor, which converts a double into a formatted string using the supplied
* decimal format. This constructor is not thread-safe.
*
* @param formatter
* the DecimalFormat
* @throws NullPointerException
* if formatter is null
*/
public FmtNumber(final DecimalFormat formatter) {
super();
checkPreconditions(formatter);
this.formatter = formatter;
this.decimalFormat = null;
}
/**
* Constructs a new FmtNumber processor, which converts a double into a formatted string using the supplied
* decimal format, then calls the next processor in the chain. This constructor is not thread-safe.
*
* @param formatter
* the DecimalFormat
* @param next
* the next processor in the chain
* @throws NullPointerException
* if formatter or next is null
*/
public FmtNumber(final DecimalFormat formatter, final StringCellProcessor next) {
super(next);
checkPreconditions(formatter);
this.formatter = formatter;
this.decimalFormat = null;
}
/**
* Checks the preconditions for creating a new FmtNumber processor with a date format String.
*
* @param dateFormat
* the date format String
* @throws NullPointerException
* if dateFormat is null
*/
private static void checkPreconditions(final String dateFormat) {
if( dateFormat == null ) {
throw new NullPointerException("dateFormat should not be null");
}
}
/**
* Checks the preconditions for creating a new FmtNumber processor with a DecimalFormat.
*
* @param formatter
* the DecimalFormat
* @throws NullPointerException
* if formatter is null
*/
private static void checkPreconditions(final DecimalFormat formatter) {
if( formatter == null ) {
throw new NullPointerException("formatter should not be null");
}
}
/**
* {@inheritDoc}
*
* @throws SuperCsvCellProcessorException
* if value is null or not a Number, or if an invalid decimalFormat String was supplied
*/
public Object execute(final Object value, final CsvContext context) {
validateInputNotNull(value, context);
if( !(value instanceof Number) ) {
throw new SuperCsvCellProcessorException(Number.class, value, context, this);
}
// create a new DecimalFormat if one is not supplied
final DecimalFormat decimalFormatter;
try {
decimalFormatter = formatter != null ? formatter : new DecimalFormat(decimalFormat);
}
catch(IllegalArgumentException e) {
throw new SuperCsvCellProcessorException(
String.format("'%s' is not a valid decimal format", decimalFormat), context, this, e);
}
final String result = decimalFormatter.format(value);
return next.execute(result, context);
}
}