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 023import org.springframework.lang.Nullable; 024 025/** 026 * A general-purpose number formatter using NumberFormat's number style. 027 * 028 * <p>Delegates to {@link java.text.NumberFormat#getInstance(Locale)}. 029 * Configures BigDecimal parsing so there is no loss in precision. 030 * Allows configuration over the decimal number pattern. 031 * The {@link #parse(String, Locale)} routine always returns a BigDecimal. 032 * 033 * @author Keith Donald 034 * @author Juergen Hoeller 035 * @since 4.2 036 * @see #setPattern 037 * @see #setLenient 038 */ 039public class NumberStyleFormatter extends AbstractNumberFormatter { 040 041 @Nullable 042 private String pattern; 043 044 045 /** 046 * Create a new NumberStyleFormatter without a pattern. 047 */ 048 public NumberStyleFormatter() { 049 } 050 051 /** 052 * Create a new NumberStyleFormatter with the specified pattern. 053 * @param pattern the format pattern 054 * @see #setPattern 055 */ 056 public NumberStyleFormatter(String pattern) { 057 this.pattern = pattern; 058 } 059 060 061 /** 062 * Specify the pattern to use to format number values. 063 * If not specified, the default DecimalFormat pattern is used. 064 * @see java.text.DecimalFormat#applyPattern(String) 065 */ 066 public void setPattern(String pattern) { 067 this.pattern = pattern; 068 } 069 070 071 @Override 072 public NumberFormat getNumberFormat(Locale locale) { 073 NumberFormat format = NumberFormat.getInstance(locale); 074 if (!(format instanceof DecimalFormat)) { 075 if (this.pattern != null) { 076 throw new IllegalStateException("Cannot support pattern for non-DecimalFormat: " + format); 077 } 078 return format; 079 } 080 DecimalFormat decimalFormat = (DecimalFormat) format; 081 decimalFormat.setParseBigDecimal(true); 082 if (this.pattern != null) { 083 decimalFormat.applyPattern(this.pattern); 084 } 085 return decimalFormat; 086 } 087 088}