001/*
002 * Units of Measurement Reference Implementation
003 * Copyright (c) 2005-2017, Jean-Marie Dautelle, Werner Keil, V2COM.
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-363 nor the names of its 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 tec.units.ri.format;
031
032import java.io.IOException;
033import java.util.logging.Logger;
034
035import javax.measure.Unit;
036import javax.measure.format.ParserException;
037import javax.measure.format.UnitFormat;
038
039import tec.units.ri.AbstractUnit;
040
041/**
042 * <p>
043 * This class provides the interface for formatting and parsing {@link AbstractUnit units}.
044 * </p>
045 *
046 * <p>
047 * For all metric units, the 20 SI prefixes used to form decimal multiples and sub-multiples of SI units are recognized. For example:<br>
048 * <code>
049 * AbstractUnit.parse("m°C").equals(MetricPrefix.MILLI(Units.CELSIUS))
050 * AbstractUnit.parse("kW").equals(MetricPrefix.KILO(Units.WATT))</code>
051 * </p>
052 *
053 * @author <a href="mailto:jean-marie@dautelle.com">Jean-Marie Dautelle</a>
054 * @author <a href="mailto:units@catmedia.us">Werner Keil</a>
055 * @version 1.0.1, October 6, 2016
056 * @since 1.0
057 * 
058 */
059public abstract class AbstractUnitFormat implements UnitFormat {
060  /**
061   * serialVersionUID
062   */
063  // private static final long serialVersionUID = -2046025267890654321L;
064
065  protected static final Logger logger = Logger.getLogger(AbstractUnitFormat.class.getName());
066
067  /**
068   * Formats an object to produce a string. This is equivalent to <blockquote> {@link #format(Unit, StringBuilder) format}<code>(unit,
069   *         new StringBuilder()).toString();</code> </blockquote>
070   *
071   * @param obj
072   *          The object to format
073   * @return Formatted string.
074   * @exception IllegalArgumentException
075   *              if the Format cannot format the given object
076   */
077  public final String format(Unit<?> unit) {
078    if (unit instanceof AbstractUnit) {
079      return format((AbstractUnit<?>) unit, new StringBuilder()).toString();
080    } else {
081      try {
082        return (this.format(unit, new StringBuilder())).toString();
083      } catch (IOException ex) {
084        throw new ParserException(ex); // Should never happen.
085      }
086    }
087  }
088
089  /**
090   * Formats the specified unit.
091   *
092   * @param unit
093   *          the unit to format.
094   * @param appendable
095   *          the appendable destination.
096   * @return The appendable destination passed in as {@code appendable}, with formatted text appended.
097   * @throws IOException
098   *           if an error occurs.
099   */
100  public abstract Appendable format(Unit<?> unit, Appendable appendable) throws IOException;
101
102  /**
103   * Parses a portion of the specified <code>CharSequence</code> from the specified position to produce a unit. If there is no unit to parse
104   * {@link AbstractUnit#ONE} is returned.
105   *
106   * @param csq
107   *          the <code>CharSequence</code> to parse.
108   * @param index
109   *          the current parsing index.
110   * @return the unit parsed from the specified character sub-sequence.
111   * @throws IllegalArgumentException
112   *           if any problem occurs while parsing the specified character sequence (e.g. illegal syntax).
113   */
114  protected abstract Unit<?> parse(CharSequence csq, int index) throws IllegalArgumentException;
115
116  public boolean isLocaleSensitive() {
117    return false;
118  }
119
120  /**
121   * Convenience method equivalent to {@link #format(AbstractUnit, Appendable)} except it does not raise an IOException.
122   *
123   * @param unit
124   *          the unit to format.
125   * @param dest
126   *          the appendable destination.
127   * @return the specified <code>StringBuilder</code>.
128   */
129  final StringBuilder format(AbstractUnit<?> unit, StringBuilder dest) {
130    try {
131      return (StringBuilder) this.format(unit, (Appendable) dest);
132    } catch (IOException ex) {
133      throw new ParserException(ex); // Should never happen.
134    }
135  }
136}