001/* 002 * Copyright 2002-2017 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.format.number; 018 019import java.text.DecimalFormat; 020import java.text.NumberFormat; 021import java.util.Locale; 022 023/** 024 * A general-purpose number formatter using NumberFormat's number style. 025 * 026 * <p>Delegates to {@link java.text.NumberFormat#getInstance(Locale)}. 027 * Configures BigDecimal parsing so there is no loss in precision. 028 * Allows configuration over the decimal number pattern. 029 * The {@link #parse(String, Locale)} routine always returns a BigDecimal. 030 * 031 * @author Keith Donald 032 * @author Juergen Hoeller 033 * @since 4.2 034 * @see #setPattern 035 * @see #setLenient 036 */ 037public class NumberStyleFormatter extends AbstractNumberFormatter { 038 039 private String pattern; 040 041 042 /** 043 * Create a new NumberStyleFormatter without a pattern. 044 */ 045 public NumberStyleFormatter() { 046 } 047 048 /** 049 * Create a new NumberStyleFormatter with the specified pattern. 050 * @param pattern the format pattern 051 * @see #setPattern 052 */ 053 public NumberStyleFormatter(String pattern) { 054 this.pattern = pattern; 055 } 056 057 058 /** 059 * Specify the pattern to use to format number values. 060 * If not specified, the default DecimalFormat pattern is used. 061 * @see java.text.DecimalFormat#applyPattern(String) 062 */ 063 public void setPattern(String pattern) { 064 this.pattern = pattern; 065 } 066 067 068 @Override 069 public NumberFormat getNumberFormat(Locale locale) { 070 NumberFormat format = NumberFormat.getInstance(locale); 071 if (!(format instanceof DecimalFormat)) { 072 if (this.pattern != null) { 073 throw new IllegalStateException("Cannot support pattern for non-DecimalFormat: " + format); 074 } 075 return format; 076 } 077 DecimalFormat decimalFormat = (DecimalFormat) format; 078 decimalFormat.setParseBigDecimal(true); 079 if (this.pattern != null) { 080 decimalFormat.applyPattern(this.pattern); 081 } 082 return decimalFormat; 083 } 084 085}