SpeedFormatter.java
/*
* Copyright (C) 2018 Alberto Irurueta Carro (alberto@irurueta.com)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.irurueta.units;
import java.text.ParseException;
import java.util.Locale;
/**
* Formats and parses speed value and unit.
*/
public class SpeedFormatter extends MeasureFormatter<Speed, SpeedUnit> {
/**
* Meters per second symbol.
*/
public static final String METERS_PER_SECOND = "m/s";
/**
* Kilometers per hour symbol.
*/
public static final String KILOMETERS_PER_HOUR = "Km/h";
/**
* Kilometers per second symbol.
*/
public static final String KILOMETERS_PER_SECOND = "Km/s";
/**
* Feet per second symbol.
*/
public static final String FEET_PER_SECOND = "ft/s";
/**
* Miles per hour symbol.
*/
public static final String MILES_PER_HOUR = "mph";
/**
* Constructor.
*/
public SpeedFormatter() {
super();
}
/**
* Constructor with locale.
*
* @param locale locale.
* @throws IllegalArgumentException if locale is null.
*/
public SpeedFormatter(final Locale locale) {
super(locale);
}
/**
* Copy constructor.
*
* @param formatter input instance to copy from.
* @throws NullPointerException if provided formatter is null.
*/
public SpeedFormatter(final SpeedFormatter formatter) {
this(formatter.getLocale());
}
/**
* Determines if two speed formatters are equal by comparing all of their internal
* parameters.
*
* @param obj another object to compare.
* @return true if provided object is assumed to be equal to this instance.
*/
@Override
public boolean equals(final Object obj) {
final var equals = super.equals(obj);
return (obj instanceof SpeedFormatter) && equals;
}
/**
* Hash code generated for this instance.
* Hash codes can be internally used by some collections to coarsely compare objects.
* This implementation only calls parent implementation to avoid static analyzer warning.
*
* @return hash code.
*/
@Override
public int hashCode() {
return super.hashCode();
}
/**
* Gets unit system for detected unit into provided string representation
* of a measurement.
*
* @param source a measurement string representation to be checked.
* @return a unit system (either metric or imperial) or null if unit
* cannot be determined.
*/
@Override
public UnitSystem getUnitSystem(final String source) {
final var unit = findUnit(source);
return unit != null ? SpeedUnit.getUnitSystem(unit) : null;
}
/**
* Parses provided string and tries to determine speed value and unit.
*
* @param source a string to be parsed.
* @return a speed containing a value and unit.
* @throws ParseException if provided string cannot be parsed.
* @throws UnknownUnitException if unit cannot be determined.
*/
@Override
public Speed parse(final String source) throws ParseException, UnknownUnitException {
return internalParse(source, new Speed());
}
/**
* Attempts to determine a speed unit within a measurement string representation.
*
* @param source a measurement string representation.
* @return a speed unit, or null if none can be determined.
*/
@Override
public SpeedUnit findUnit(final String source) {
if (source.contains(KILOMETERS_PER_HOUR + " ") || source.endsWith(KILOMETERS_PER_HOUR)) {
return SpeedUnit.KILOMETERS_PER_HOUR;
}
if (source.contains(KILOMETERS_PER_SECOND + " ") || source.endsWith(KILOMETERS_PER_SECOND)) {
return SpeedUnit.KILOMETERS_PER_SECOND;
}
if (source.contains(FEET_PER_SECOND + " ") || source.endsWith(FEET_PER_SECOND)) {
return SpeedUnit.FEET_PER_SECOND;
}
if (source.contains(MILES_PER_HOUR + " ") || source.endsWith(MILES_PER_HOUR)) {
return SpeedUnit.MILES_PER_HOUR;
}
if (source.contains(METERS_PER_SECOND + " ") || source.endsWith(METERS_PER_SECOND)) {
return SpeedUnit.METERS_PER_SECOND;
}
return null;
}
/**
* Formats and converts provided speed value and unit using provided
* unit system.
* If provided value is too large for provided unit, this method will
* convert it to a more appropriate unit using provided unit system (either
* metric or imperial).
*
* @param value a speed value.
* @param unit a speed unit.
* @param system system unit to convert speed to.
* @return a string representation of speed value and unit.
*/
@Override
public String formatAndConvert(final Number value, final SpeedUnit unit, final UnitSystem system) {
if (system == UnitSystem.IMPERIAL) {
return formatAndConvertImperial(value, unit);
} else {
return formatAndConvertMetric(value, unit);
}
}
/**
* Formats and converts provided speed value and unit using metric unit
* system.
* If provided speed value is too large for provided speed unit,
* this method will convert it to a more appropriate unit.
*
* @param value a speed value.
* @param unit a speed unit.
* @return a string representation of speed value and unit using metric
* unit system.
*/
public String formatAndConvertMetric(final Number value, final SpeedUnit unit) {
final var v = value.doubleValue();
final var metersPerSecond = SpeedConverter.convert(v, unit, SpeedUnit.METERS_PER_SECOND);
if (Math.abs(metersPerSecond) < SpeedConverter.METERS_PER_KILOMETER / SpeedConverter.SECONDS_PER_HOUR) {
return format(metersPerSecond, SpeedUnit.METERS_PER_SECOND);
}
final var kilometersPerHour = SpeedConverter.convert(v, unit, SpeedUnit.KILOMETERS_PER_HOUR);
if (Math.abs(kilometersPerHour) < SpeedConverter.SECONDS_PER_HOUR) {
return format(kilometersPerHour, SpeedUnit.KILOMETERS_PER_HOUR);
}
final var kilometersPerSecond = SpeedConverter.convert(v, unit, SpeedUnit.KILOMETERS_PER_SECOND);
return format(kilometersPerSecond, SpeedUnit.KILOMETERS_PER_SECOND);
}
/**
* Formats and converts provided speed value and unit using imperial unit
* system.
* If provided speed value is too large for provided speed unit,
* this method will convert it to a more appropriate unit.
*
* @param value a speed value.
* @param unit a speed unit.
* @return a string representation of speed value and unit using imperial
* unit system.
*/
public String formatAndConvertImperial(final Number value, final SpeedUnit unit) {
final var v = value.doubleValue();
final double feetPerSecond = SpeedConverter.convert(v, unit, SpeedUnit.FEET_PER_SECOND);
if (Math.abs(feetPerSecond) < SpeedConverter.METERS_PER_MILE
/ SpeedConverter.SECONDS_PER_HOUR / SpeedConverter.METERS_PER_FOOT) {
return format(feetPerSecond, SpeedUnit.FEET_PER_SECOND);
}
final var milesPerHour = SpeedConverter.convert(v, unit, SpeedUnit.MILES_PER_HOUR);
return format(milesPerHour, SpeedUnit.MILES_PER_HOUR);
}
/**
* Returns unit string representation.
*
* @param unit a speed unit.
* @return its string representation.
*/
@SuppressWarnings("DuplicatedCode")
@Override
public String getUnitSymbol(final SpeedUnit unit) {
return switch (unit) {
case KILOMETERS_PER_HOUR -> KILOMETERS_PER_HOUR;
case KILOMETERS_PER_SECOND -> KILOMETERS_PER_SECOND;
case FEET_PER_SECOND -> FEET_PER_SECOND;
case MILES_PER_HOUR -> MILES_PER_HOUR;
default -> METERS_PER_SECOND;
};
}
}