001/* 002 * Units of Measurement Reference Implementation 003 * Copyright (c) 2005-2018, Jean-Marie Dautelle, Werner Keil, Otavio Santana. 004 * 005 * All rights reserved. 006 * 007 * Redistribution and use in source and binary forms, with or without modification, 008 * are permitted provided that the following conditions are met: 009 * 010 * 1. Redistributions of source code must retain the above copyright notice, 011 * this list of conditions and the following disclaimer. 012 * 013 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions 014 * and the following disclaimer in the documentation and/or other materials provided with the distribution. 015 * 016 * 3. Neither the name of JSR-385, Indriya nor the names of their contributors may be used to endorse or promote products 017 * derived from this software without specific prior written permission. 018 * 019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 020 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 021 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 022 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE 023 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 026 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 028 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 029 */ 030package tech.units.indriya.format; 031 032import javax.measure.Quantity; 033import javax.measure.Unit; 034import javax.measure.format.ParserException; 035 036import tech.units.indriya.AbstractUnit; 037import tech.units.indriya.internal.format.TokenException; 038import tech.units.indriya.internal.format.TokenMgrError; 039import tech.units.indriya.internal.format.UnitFormatParser; 040import tech.units.indriya.unit.AnnotatedUnit; 041 042import java.io.IOException; 043import java.io.StringReader; 044import java.text.ParsePosition; 045import java.util.Locale; 046import java.util.ResourceBundle; 047 048/** 049 * <p> 050 * This class represents the local neutral format. 051 * </p> 052 * 053 * <h3>Here is the grammar for Units in Extended Backus-Naur Form (EBNF)</h3> 054 * <p> 055 * Note that the grammar has been left-factored to be suitable for use by a 056 * top-down parser generator such as 057 * <a href="https://javacc.dev.java.net/">JavaCC</a> 058 * </p> 059 * <table width="90%" align="center"> 060 * <tr> 061 * <th colspan="3" align="left">Lexical Entities:</th> 062 * </tr> 063 * <tr valign="top"> 064 * <td><sign></td> 065 * <td>:=</td> 066 * <td>"+" | "-"</td> 067 * </tr> 068 * <tr valign="top"> 069 * <td><digit></td> 070 * <td>:=</td> 071 * <td>"0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"</td> 072 * </tr> 073 * <tr valign="top"> 074 * <td><superscript_digit></td> 075 * <td>:=</td> 076 * <td>"⁰" | "¹" | "²" | "³" | "⁴" | "⁵" | "⁶" | "⁷" | "⁸" | "⁹"</td> 077 * </tr> 078 * <tr valign="top"> 079 * <td><integer></td> 080 * <td>:=</td> 081 * <td>(<digit>)+</td> 082 * </tr> 083 * <tr valign="top"> 084 * <td><number></td> 085 * <td>:=</td> 086 * <td>(<sign>)? (<digit>)* (".")? (<digit>)+ (("e" | "E") 087 * (<sign>)? (<digit>)+)?</td> 088 * </tr> 089 * <tr valign="top"> 090 * <td><exponent></td> 091 * <td>:=</td> 092 * <td>( "^" ( <sign> )? <integer> ) <br> 093 * | ( "^(" (<sign>)? <integer> ( "/" (<sign>)? 094 * <integer> )? ")" ) <br> 095 * | ( <superscript_digit> )+</td> 096 * </tr> 097 * <tr valign="top"> 098 * <td><initial_char></td> 099 * <td>:=</td> 100 * <td>? Any Unicode character excluding the following: ASCII control & 101 * whitespace (\u0000 - \u0020), decimal digits '0'-'9', '(' 102 * (\u0028), ')' (\u0029), '*' (\u002A), '+' (\u002B), '-' 103 * (\u002D), '.' (\u002E), '/' (\u005C), ':' (\u003A), '^' 104 * (\u005E), '²' (\u00B2), '³' (\u00B3), '·' (\u00B7), '¹' 105 * (\u00B9), '⁰' (\u2070), '⁴' (\u2074), '⁵' (\u2075), '⁶' 106 * (\u2076), '⁷' (\u2077), '⁸' (\u2078), '⁹' (\u2079) ?</td> 107 * </tr> 108 * <tr valign="top"> 109 * <td><unit_identifier></td> 110 * <td>:=</td> 111 * <td><initial_char> ( <initial_char> | <digit> )*</td> 112 * </tr> 113 * <tr> 114 * <th colspan="3" align="left">Non-Terminals:</th> 115 * </tr> 116 * <tr valign="top"> 117 * <td><unit_expr></td> 118 * <td>:=</td> 119 * <td><compound_expr></td> 120 * </tr> 121 * <tr valign="top"> 122 * <td><compound_expr></td> 123 * <td>:=</td> 124 * <td><add_expr> ( ":" <add_expr> )*</td> 125 * </tr> 126 * <tr valign="top"> 127 * <td><add_expr></td> 128 * <td>:=</td> 129 * <td>( <number> <sign> )? <mul_expr> ( <sign> 130 * <number> )?</td> 131 * </tr> 132 * <tr valign="top"> 133 * <td><mul_expr></td> 134 * <td>:=</td> 135 * <td><exponent_expr> ( ( ( "*" | "·" ) <exponent_expr> ) | ( "/" 136 * <exponent_expr> ) )*</td> 137 * </tr> 138 * <tr valign="top"> 139 * <td><exponent_expr></td> 140 * <td>:=</td> 141 * <td>( <atomic_expr> ( <exponent> )? ) <br> 142 * | (<integer> "^" <atomic_expr>) <br> 143 * | ( ( "log" ( <integer> )? ) | "ln" ) "(" <add_expr> ")" )</td> 144 * </tr> 145 * <tr valign="top"> 146 * <td><atomic_expr></td> 147 * <td>:=</td> 148 * <td><number> <br> 149 * | <unit_identifier> <br> 150 * | ( "(" <add_expr> ")" )</td> 151 * </tr> 152 * </table> 153 * 154 * @author <a href="mailto:eric-r@northwestern.edu">Eric Russell</a> 155 * @author <a href="mailto:units@catmedia.us">Werner Keil</a> 156 * @version 1.1, $Date: 2018-04-05 $ 157 * @since 1.0 158 */ 159public class EBNFUnitFormat extends AbstractUnitFormat { 160 161 // //////////////////////////////////////////////////// 162 // Class variables // 163 // //////////////////////////////////////////////////// 164 165 /** 166 * 167 */ 168 // private static final long serialVersionUID = 8968559300292910840L; 169 170 /** 171 * Name of the resource bundle 172 */ 173 private static final String BUNDLE_NAME = "tech.units.indriya.format.messages"; //$NON-NLS-1$ 174 175 /** 176 * Default locale instance. If the default locale is changed after the class is 177 * initialized, this instance will no longer be used. 178 */ 179 private static final EBNFUnitFormat DEFAULT_INSTANCE = new EBNFUnitFormat(); 180 181 /** 182 * Returns the instance for the current default locale (non-ascii characters are 183 * allowed) 184 */ 185 public static EBNFUnitFormat getInstance() { 186 return DEFAULT_INSTANCE; 187 } 188 189 /** Returns an instance for the given symbol map. */ 190 public static EBNFUnitFormat getInstance(SymbolMap symbols) { 191 return new EBNFUnitFormat(symbols); 192 } 193 194 // ////////////////////// 195 // Instance variables // 196 // ////////////////////// 197 /** 198 * The symbol map used by this instance to map between 199 * {@link org.unitsofmeasure.Unit Unit}s and <code>String</code>s, etc... 200 */ 201 private final transient SymbolMap symbolMap; 202 203 // //////////////// 204 // Constructors // 205 // //////////////// 206 /** 207 * Base constructor. 208 * 209 */ 210 EBNFUnitFormat() { 211 this(SymbolMap.of(ResourceBundle.getBundle(BUNDLE_NAME, Locale.ROOT))); 212 } 213 214 /** 215 * Private constructor. 216 * 217 * @param symbols 218 * the symbol mapping. 219 */ 220 private EBNFUnitFormat(SymbolMap symbols) { 221 symbolMap = symbols; 222 } 223 224 // ////////////////////// 225 // Instance methods // 226 // ////////////////////// 227 /** 228 * Get the symbol map used by this instance to map between 229 * {@link org.unitsofmeasure.Unit Unit}s and <code>String</code>s, etc... 230 * 231 * @return SymbolMap the current symbol map 232 */ 233 protected SymbolMap getSymbols() { 234 return symbolMap; 235 } 236 237 // ////////////// 238 // Formatting // 239 // ////////////// 240 public Appendable format(Unit<?> unit, Appendable appendable) throws IOException { 241 242 EBNFHelper.formatInternal(unit, appendable, symbolMap); 243 if (unit instanceof AnnotatedUnit<?>) { 244 AnnotatedUnit<?> annotatedUnit = (AnnotatedUnit<?>) unit; 245 if (annotatedUnit.getAnnotation() != null) { 246 appendable.append('{'); 247 appendable.append(annotatedUnit.getAnnotation()); 248 appendable.append('}'); 249 } 250 } 251 // TODO add support for CompoundUnit similar to AnnotatedUnit 252 return appendable; 253 } 254 255 @Override 256 protected Unit<? extends Quantity<?>> parse(CharSequence csq, ParsePosition cursor) throws ParserException { 257 // Parsing reads the whole character sequence from the parse position. 258 int start = cursor != null ? cursor.getIndex() : 0; 259 int end = csq.length(); 260 if (end <= start) { 261 return AbstractUnit.ONE; 262 } 263 String source = csq.subSequence(start, end).toString().trim(); 264 if (source.length() == 0) { 265 return AbstractUnit.ONE; 266 } 267 try { 268 UnitFormatParser parser = new UnitFormatParser(symbolMap, new StringReader(source)); 269 Unit<?> result = parser.parseUnit(); 270 if (cursor != null) 271 cursor.setIndex(end); 272 return result; 273 } catch (TokenException e) { 274 if (e.currentToken != null) { 275 cursor.setErrorIndex(start + e.currentToken.endColumn); 276 } else { 277 cursor.setErrorIndex(start); 278 } 279 throw new ParserException(e); 280 } catch (TokenMgrError e) { 281 cursor.setErrorIndex(start); 282 throw new IllegalArgumentException(e.getMessage()); 283 } 284 } 285 286 @Override 287 protected Unit<?> parse(CharSequence csq, int index) throws IllegalArgumentException { 288 return parse(csq, new ParsePosition(index)); 289 } 290 291 public Unit<?> parse(CharSequence csq) throws ParserException { 292 return parse(csq, 0); 293 } 294 295 @Override 296 public boolean isLocaleSensitive() { 297 return false; 298 } 299}