Created the new BaseUnit, Unit and AbstractUnit implementations.

1 files changed, 145 insertions, 0 deletions

diff --git a/src/org/unitConverter/newUnits/Unit.java b/src/org/unitConverter/newUnits/Unit.java
new file mode 100644
index 0000000..339afde
--- /dev/null
+++ b/src/org/unitConverter/newUnits/Unit.java
@@ -0,0 +1,145 @@
+/**
+ * Copyright (C) 2019 Adrien Hopkins
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package org.unitConverter.newUnits;
+
+import java.util.Objects;
+import java.util.function.DoubleUnaryOperator;
+
+import org.unitConverter.dimension.BaseDimension;
+import org.unitConverter.math.ObjectProduct;
+
+/**
+ * @author Adrien Hopkins
+ * @since 2019-10-16
+ */
+public interface Unit {
+	/**
+	 * Returns a unit from its base and the functions it uses to convert to and from its base.
+	 * 
+	 * <p>
+	 * For example, to get a unit representing the degree Celsius, the following code can be used:
+	 * 
+	 * {@code Unit.fromConversionFunctions(SI.KELVIN, tempK -> tempK - 273.15, tempC -> tempC + 273.15);}
+	 * </p>
+	 * 
+	 * @param base
+	 *            unit's base
+	 * @param converterFrom
+	 *            function that accepts a value expressed in the unit's base and returns that value expressed in this
+	 *            unit.
+	 * @param converterTo
+	 *            function that accepts a value expressed in the unit and returns that value expressed in the unit's
+	 *            base.
+	 * @return a unit that uses the provided functions to convert.
+	 * @since 2019-05-22
+	 * @throws NullPointerException
+	 *             if any argument is null
+	 */
+	public static Unit fromConversionFunctions(final ObjectProduct<BaseUnit> base,
+			final DoubleUnaryOperator converterFrom, final DoubleUnaryOperator converterTo) {
+		return FunctionalUnit.valueOf(base, converterFrom, converterTo);
+	}
+
+	/**
+	 * Checks if a value expressed in this unit can be converted to a value expressed in {@code other}
+	 * 
+	 * @param other
+	 *            unit to test with
+	 * @return true if the units are compatible
+	 * @since 2019-01-13
+	 * @since v0.1.0
+	 * @throws NullPointerException
+	 *             if other is null
+	 */
+	default boolean canConvertTo(final Unit other) {
+		Objects.requireNonNull(other, "other must not be null.");
+		return Objects.equals(this.getBase(), other.getBase());
+	}
+
+	/**
+	 * Converts from a value expressed in this unit's base unit to a value expressed in this unit.
+	 * <p>
+	 * This must be the inverse of {@code convertToBase}, so {@code convertFromBase(convertToBase(value))} must be equal
+	 * to {@code value} for any value, ignoring precision loss by roundoff error.
+	 * </p>
+	 * <p>
+	 * If this unit <i>is</i> a base unit, this method should return {@code value}.
+	 * </p>
+	 * 
+	 * @param value
+	 *            value expressed in <b>base</b> unit
+	 * @return value expressed in <b>this</b> unit
+	 * @since 2018-12-22
+	 * @since v0.1.0
+	 */
+	double convertFromBase(double value);
+
+	/**
+	 * Converts a value expressed in this unit to a value expressed in {@code other}.
+	 * 
+	 * @param other
+	 *            unit to convert to
+	 * @param value
+	 *            value to convert
+	 * @return converted value
+	 * @since 2019-05-22
+	 * @throws IllegalArgumentException
+	 *             if {@code other} is incompatible for conversion with this unit (as tested by
+	 *             {@link Unit#canConvertTo}).
+	 * @throws NullPointerException
+	 *             if other is null
+	 */
+	default double convertTo(final Unit other, final double value) {
+		Objects.requireNonNull(other, "other must not be null.");
+		if (this.canConvertTo(other))
+			return other.convertFromBase(this.convertToBase(value));
+		else
+			throw new IllegalArgumentException(String.format("Cannot convert from %s to %s.", this, other));
+	}
+
+	/**
+	 * Converts from a value expressed in this unit to a value expressed in this unit's base unit.
+	 * <p>
+	 * This must be the inverse of {@code convertFromBase}, so {@code convertToBase(convertFromBase(value))} must be
+	 * equal to {@code value} for any value, ignoring precision loss by roundoff error.
+	 * </p>
+	 * <p>
+	 * If this unit <i>is</i> a base unit, this method should return {@code value}.
+	 * </p>
+	 * 
+	 * @param value
+	 *            value expressed in <b>this</b> unit
+	 * @return value expressed in <b>base</b> unit
+	 * @since 2018-12-22
+	 * @since v0.1.0
+	 */
+	double convertToBase(double value);
+
+	/**
+	 * @return combination of units that this unit is based on
+	 * @since 2018-12-22
+	 * @since v0.1.0
+	 */
+	ObjectProduct<BaseUnit> getBase();
+
+	/**
+	 * @return dimension measured by this unit
+	 * @since 2018-12-22
+	 * @since v0.1.0
+	 */
+	ObjectProduct<BaseDimension> getDimension();
+}
\ No newline at end of file