Print nonfinal unit set coefficients as integers

These values are guaranteed to be integers, so printing them without a
decimal point looks nicer and saves space.

1 files changed, 34 insertions, 12 deletions

diff --git a/src/main/java/sevenUnitsGUI/Presenter.java b/src/main/java/sevenUnitsGUI/Presenter.java
index f085dba..1244401 100644
--- a/src/main/java/sevenUnitsGUI/Presenter.java
+++ b/src/main/java/sevenUnitsGUI/Presenter.java
@@ -162,6 +162,16 @@ public final class Presenter {
 		return Presenter.class.getResourceAsStream(filepath);
 	}
 	
+	/**
+	 * Convert a linear unit value to a string, where the number is rounded to
+	 * the nearest integer.
+	 *
+	 * @since 2024-08-16
+	 */
+	private static final String linearUnitValueIntToString(LinearUnitValue uv) {
+		return Long.toString(Math.round(uv.getValueExact())) + " " + uv.getUnit();
+	}
+	
 	private static Map.Entry<String, String> parseSettingLine(String line) {
 		final int equalsIndex = line.indexOf('=');
 		if (equalsIndex == -1)
@@ -179,6 +189,8 @@ public final class Presenter {
 		return CONFIG_FILE.getParent().resolve(pathname);
 	}
 	
+	// ====== SETTINGS ======
+	
 	private static String searchRuleToString(
 			Function<Map.Entry<String, LinearUnit>, Map<String, LinearUnit>> searchRule) {
 		if (PrefixSearchRule.NO_PREFIXES.equals(searchRule))
@@ -191,8 +203,6 @@ public final class Presenter {
 			return searchRule.toString();
 	}
 	
-	// ====== SETTINGS ======
-	
 	/**
 	 * @return true iff a and b have any elements in common
 	 * @since 2022-04-19
@@ -519,9 +529,7 @@ public final class Presenter {
 			return Optional.empty();
 		}
 		
-		final String toExpression = toValues.stream().map(
-				v -> this.numberDisplayRule.apply(v.getValue()) + " " + v.getUnit())
-				.collect(Collectors.joining(" + "));
+		final String toExpression = this.linearUnitValueSumToString(toValues);
 		return Optional.of(
 				UnitConversionRecord.valueOf(fromExpression, toExpression, "", ""));
 	}
@@ -553,9 +561,7 @@ public final class Presenter {
 			return Optional.empty();
 		}
 		
-		final String toExpression = toValues.stream().map(
-				v -> this.numberDisplayRule.apply(v.getValue()) + " " + v.getUnit())
-				.collect(Collectors.joining(" + "));
+		final String toExpression = this.linearUnitValueSumToString(toValues);
 		return Optional.of(
 				UnitConversionRecord.valueOf(fromExpression, toExpression, "", ""));
 	}
@@ -649,9 +655,7 @@ public final class Presenter {
 		
 		final List<LinearUnitValue> converted = initValue
 				.convertToMultiple(toMulti);
-		final String toExpression = converted.stream().map(
-				v -> this.numberDisplayRule.apply(v.getValue()) + " " + v.getUnit())
-				.collect(Collectors.joining(" + "));
+		final String toExpression = this.linearUnitValueSumToString(converted);
 		return UnitConversionRecord.valueOf(fromUnitString, toExpression,
 				inputValueString, "");
 		
@@ -779,6 +783,24 @@ public final class Presenter {
 				|| sharesAnyElements(this.metricExceptions, u.getOtherNames());
 	}
 	
+	/**
+	 * Convert a list of LinearUnitValues that you would get from a unit-set
+	 * conversion to a string. All but the last have their numbers rendered as
+	 * integers, since they are always integers. The last one follows the usual
+	 * number display rule.
+	 *
+	 * @since 2024-08-16
+	 */
+	private final String linearUnitValueSumToString(
+			List<LinearUnitValue> values) {
+		final String integerPart = values.subList(0, values.size() - 1).stream()
+				.map(Presenter::linearUnitValueIntToString)
+				.collect(Collectors.joining(" + "));
+		final LinearUnitValue last = values.get(values.size() - 1);
+		return integerPart + " + " + this.numberDisplayRule.apply(last.getValue())
+				+ " " + last.getUnit();
+	}
+	
 	private void loadExceptionFile(Path exceptionFile) {
 		try (Stream<String> lines = Files.lines(exceptionFile)) {
 			lines.map(Presenter::withoutComments)
@@ -847,7 +869,7 @@ public final class Presenter {
 	 * @return true iff the One-Way Conversion feature is available (views that
 	 *         show units as a list will have metric units removed from the From
 	 *         unit list and imperial/USC units removed from the To unit list)
-	 * 			
+	 * 
 	 * @since 2022-03-30
 	 */
 	public boolean oneWayConversionEnabled() {