001/*
002 * SonarQube
003 * Copyright (C) 2009-2017 SonarSource SA
004 * mailto:info AT sonarsource DOT com
005 *
006 * This program is free software; you can redistribute it and/or
007 * modify it under the terms of the GNU Lesser General Public
008 * License as published by the Free Software Foundation; either
009 * version 3 of the License, or (at your option) any later version.
010 *
011 * This program is distributed in the hope that it will be useful,
012 * but WITHOUT ANY WARRANTY; without even the implied warranty of
013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014 * Lesser General Public License for more details.
015 *
016 * You should have received a copy of the GNU Lesser General Public License
017 * along with this program; if not, write to the Free Software Foundation,
018 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
019 */
020package org.sonar.api.utils;
021
022import java.math.BigDecimal;
023import java.math.RoundingMode;
024import java.text.NumberFormat;
025import java.text.ParseException;
026import java.util.Locale;
027
028/**
029 * Utility to parse various inputs
030 *
031 * @since 1.10
032 */
033public final class ParsingUtils {
034
035  private ParsingUtils() {
036  }
037
038  /**
039   * Parses a string with a locale and returns the corresponding number
040   *
041   * @throws ParseException if number cannot be parsed
042   */
043  public static double parseNumber(String number, Locale locale) throws ParseException {
044    if ("".equals(number)) {
045      return Double.NaN;
046    }
047    return NumberFormat.getNumberInstance(locale).parse(number).doubleValue();
048  }
049
050  /**
051   * Parses a string with the default locale and returns the corresponding number
052   *
053   * @throws ParseException if number cannot be parsed
054   */
055  public static double parseNumber(String number) throws ParseException {
056    return parseNumber(number, Locale.getDefault());
057  }
058
059  /**
060   * Scales a double value, taking into account 2 decimals
061   */
062  public static double scaleValue(double value) {
063    return scaleValue(value, 2);
064  }
065
066  /**
067   * Scales a double value with decimals
068   */
069  public static double scaleValue(double value, int decimals) {
070    BigDecimal bd = BigDecimal.valueOf(value);
071    return bd.setScale(decimals, RoundingMode.HALF_UP).doubleValue();
072  }
073
074}