
org.springframework.util.NumberUtils Maven / Gradle / Ivy
/*
* Copyright 2002-2005 the original author or authors.
*
* 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.springframework.util;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.text.NumberFormat;
import java.text.ParseException;
/**
* Miscellaneous utility methods for number conversion and parsing.
* Mainly for internal use within the framework; consider Jakarta's
* Commons Lang for a more comprehensive suite of string utilities.
*
* @author Juergen Hoeller
* @author Rob Harrop
* @since 1.1.2
*/
public abstract class NumberUtils {
/**
* Convert the given number into an instance of the given target class.
* @param number the number to convert
* @param targetClass the target class to convert to
* @return the converted number
* @throws IllegalArgumentException if the target class is not supported
* (i.e. not a standard Number subclass as included in the JDK)
* @see java.lang.Byte
* @see java.lang.Short
* @see java.lang.Integer
* @see java.lang.Long
* @see java.math.BigInteger
* @see java.lang.Float
* @see java.lang.Double
* @see java.math.BigDecimal
*/
public static Number convertNumberToTargetClass(Number number, Class targetClass)
throws IllegalArgumentException {
if (targetClass.isInstance(number)) {
return number;
}
else if(targetClass.equals(Byte.class)) {
return new Byte(number.byteValue());
}
else if (targetClass.equals(Short.class)) {
return new Short(number.shortValue());
}
else if (targetClass.equals(Integer.class)) {
return new Integer(number.intValue());
}
else if (targetClass.equals(Long.class)) {
return new Long(number.longValue());
}
else if (targetClass.equals(Float.class)) {
return new Float(number.floatValue());
}
else if (targetClass.equals(Double.class)) {
return new Double(number.doubleValue());
}
else if (targetClass.equals(BigInteger.class)) {
return BigInteger.valueOf(number.longValue());
}
else if (targetClass.equals(BigDecimal.class)) {
// using BigDecimal(String) here, to avoid unpredictability of BigDecimal(double)
// (see BigDecimal javadoc for details)
return new BigDecimal(number.toString());
}
else {
throw new IllegalArgumentException("Couldn't convert number [" + number +
"] to target class [" + targetClass.getName() + "]");
}
}
/**
* Parse the given text into a number instance of the given target class,
* using the corresponding default valueOf
methods. Trims the
* input String
before attempting to parse the number.
* @param text the text to convert
* @param targetClass the target class to parse into
* @return the parsed number
* @throws IllegalArgumentException if the target class is not supported
* (i.e. not a standard Number subclass as included in the JDK)
* @see java.lang.Byte#valueOf
* @see java.lang.Short#valueOf
* @see java.lang.Integer#valueOf
* @see java.lang.Long#valueOf
* @see java.math.BigInteger#BigInteger(String)
* @see java.lang.Float#valueOf
* @see java.lang.Double#valueOf
* @see java.math.BigDecimal#BigDecimal(String)
*/
public static Number parseNumber(String text, Class targetClass) {
String trimmed = text.trim();
if(targetClass.equals(Byte.class)) {
return Byte.valueOf(trimmed);
}
else if (targetClass.equals(Short.class)) {
return Short.valueOf(trimmed);
}
else if (targetClass.equals(Integer.class)) {
return Integer.valueOf(trimmed);
}
else if (targetClass.equals(Long.class)) {
return Long.valueOf(trimmed);
}
else if (targetClass.equals(BigInteger.class)) {
return new BigInteger(trimmed);
}
else if (targetClass.equals(Float.class)) {
return Float.valueOf(trimmed);
}
else if (targetClass.equals(Double.class)) {
return Double.valueOf(trimmed);
}
else if (targetClass.equals(BigDecimal.class)) {
return new BigDecimal(trimmed);
}
else {
throw new IllegalArgumentException(
"Cannot convert [" + trimmed + "] to target class [" + targetClass.getName() + "]");
}
}
/**
* Parse the given text into a number instance of the given target class,
* using the given NumberFormat. Trims the input String
* before attempting to parse the number.
* @param text the text to convert
* @param targetClass the target class to parse into
* @param numberFormat the NumberFormat to use for parsing
* @return the parsed number
* @throws IllegalArgumentException if the target class is not supported
* (i.e. not a standard Number subclass as included in the JDK)
* @see java.text.NumberFormat#parse
* @see #convertNumberToTargetClass
*/
public static Number parseNumber(String text, Class targetClass, NumberFormat numberFormat) {
try {
Number number = numberFormat.parse(text.trim());
return convertNumberToTargetClass(number, targetClass);
}
catch (ParseException ex) {
throw new IllegalArgumentException(ex.getMessage());
}
}
}
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