Removed AbstractUnit's unit counting functionnality.

The startup unit count is now performed by the UnitDatabase.

5 files changed, 35 insertions, 63 deletions

diff --git a/src/org/unitConverter/UnitsDatabase.java b/src/org/unitConverter/UnitsDatabase.java
index 481ce93..290a425 100755
--- a/src/org/unitConverter/UnitsDatabase.java
+++ b/src/org/unitConverter/UnitsDatabase.java
@@ -24,6 +24,7 @@ import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -32,7 +33,6 @@ import java.util.Set;
 import org.unitConverter.dimension.UnitDimension;
 import org.unitConverter.math.DecimalComparison;
 import org.unitConverter.math.ExpressionParser;
-import org.unitConverter.unit.AbstractUnit;
 import org.unitConverter.unit.BaseUnit;
 import org.unitConverter.unit.DefaultUnitPrefix;
 import org.unitConverter.unit.LinearUnit;
@@ -186,10 +186,7 @@ public final class UnitsDatabase {
 							System.err.printf("Parsing error on line %d:%n", lineCounter);
 							throw e;
 						}
-						AbstractUnit.incrementUnitCounter();
-						if (unit instanceof BaseUnit) {
-							AbstractUnit.incrementBaseUnitCounter();
-						}
+
 						this.addUnit(name, unit);
 					}
 				}
@@ -564,6 +561,14 @@ public final class UnitsDatabase {
 	}
 
 	/**
+	 * @return an immutable set of all of the units in this database, ignoring prefixes.
+	 * @since 2019-04-10
+	 */
+	public Set<Unit> prefixlessUnitSet() {
+		return Collections.unmodifiableSet(new HashSet<>(this.units.values()));
+	}
+
+	/**
 	 * @return an immutable set of all of the prefix names in this database
 	 * @since 2019-01-14
 	 * @since v0.1.0
diff --git a/src/org/unitConverter/converterGUI/UnitConverterGUI.java b/src/org/unitConverter/converterGUI/UnitConverterGUI.java
index 867211c..fd40ff4 100755
--- a/src/org/unitConverter/converterGUI/UnitConverterGUI.java
+++ b/src/org/unitConverter/converterGUI/UnitConverterGUI.java
@@ -47,7 +47,7 @@ import javax.swing.ListSelectionModel;
 import org.unitConverter.UnitsDatabase;
 import org.unitConverter.dimension.StandardDimensions;
 import org.unitConverter.dimension.UnitDimension;
-import org.unitConverter.unit.AbstractUnit;
+import org.unitConverter.unit.BaseUnit;
 import org.unitConverter.unit.NonlinearUnits;
 import org.unitConverter.unit.SI;
 import org.unitConverter.unit.Unit;
@@ -143,8 +143,13 @@ final class UnitConverterGUI {
 			this.prefixNamesFiltered = new DelegateListModel<>(new ArrayList<>(this.units.prefixNameSet()));
 			this.prefixNamesFiltered.sort(this.prefixNameComparator); // sorts it using my comparator
 
-			System.out.printf("Successfully loaded %d units (%d base units)", AbstractUnit.getUnitCount(),
-					AbstractUnit.getBaseUnitCount());
+			// a Predicate that returns true iff the argument is a full base unit
+			final Predicate<Unit> isFullBase = unit -> unit instanceof BaseUnit && ((BaseUnit) unit).isFullBase();
+
+			// print out unit counts
+			System.out.printf("Successfully loaded %d units with %d unit names (%d base units).%n",
+					this.units.prefixlessUnitSet().size(), this.units.prefixlessUnitNameSet().size(),
+					this.units.prefixlessUnitSet().stream().filter(isFullBase).count());
 		}
 
 		/**
@@ -162,6 +167,11 @@ final class UnitConverterGUI {
 			final String fromUnitString = this.view.getFromText();
 			final String toUnitString = this.view.getToText();
 
+			if (fromUnitString.isEmpty()) {
+				this.view.showErrorDialog("Parse Error", "Please enter a unit expression in the From: box.");
+				return;
+			}
+
 			// try to parse from
 			final Unit from;
 			try {
@@ -175,8 +185,8 @@ final class UnitConverterGUI {
 			// try to parse to
 			final Unit to;
 			try {
-				// if it's a unit, convert to that
 				if (this.units.containsUnitName(toUnitString)) {
+					// if it's a unit, convert to that
 					to = this.units.getUnit(toUnitString);
 				} else {
 					to = this.units.getUnitFromExpression(toUnitString);
diff --git a/src/org/unitConverter/math/ExpressionParser.java b/src/org/unitConverter/math/ExpressionParser.java
index f34a0c2..b56fa71 100644
--- a/src/org/unitConverter/math/ExpressionParser.java
+++ b/src/org/unitConverter/math/ExpressionParser.java
@@ -479,6 +479,9 @@ public final class ExpressionParser<T> {
 				break;
 			}
 
+			// swap components based on what kind of operator there is
+			// 1 + 2 becomes 2 1 +
+			// - 1 becomes 1 -
 			switch (this.getTokenType(components.get(highestPriorityOperatorPosition))) {
 				case UNARY_OPERATOR:
 					final String unaryOperator = components.remove(highestPriorityOperatorPosition);
diff --git a/src/org/unitConverter/unit/AbstractUnit.java b/src/org/unitConverter/unit/AbstractUnit.java
index 6088960..a0d6f7e 100644
--- a/src/org/unitConverter/unit/AbstractUnit.java
+++ b/src/org/unitConverter/unit/AbstractUnit.java
@@ -29,60 +29,6 @@ import org.unitConverter.dimension.UnitDimension;
  */
 public abstract class AbstractUnit implements Unit {
 	/**
-	 * The number of units created, including base units.
-	 * 
-	 * @since 2019-01-02
-	 * @since v0.1.0
-	 */
-	private static long unitCount = 0;
-
-	/**
-	 * The number of base units created.
-	 * 
-	 * @since 2019-01-02
-	 * @since v0.1.0
-	 */
-	private static long baseUnitCount = 0;
-
-	/**
-	 * @return number of base units created
-	 * @since 2019-01-02
-	 * @since v0.1.0
-	 */
-	public static final long getBaseUnitCount() {
-		return baseUnitCount;
-	}
-
-	/**
-	 * @return number of units created
-	 * @since 2019-01-02
-	 * @since v0.1.0
-	 */
-	public static final long getUnitCount() {
-		return unitCount;
-	}
-
-	/**
-	 * Increments the number of base units.
-	 * 
-	 * @since 2019-01-15
-	 * @since v0.1.0
-	 */
-	public static final void incrementBaseUnitCounter() {
-		baseUnitCount++;
-	}
-
-	/**
-	 * Increments the number of units.
-	 * 
-	 * @since 2019-01-15
-	 * @since v0.1.0
-	 */
-	public static final void incrementUnitCounter() {
-		unitCount++;
-	}
-
-	/**
 	 * The dimension, or what the unit measures.
 	 * 
 	 * @since 2018-12-22
diff --git a/src/org/unitConverter/unit/BaseUnit.java b/src/org/unitConverter/unit/BaseUnit.java
index 2def48e..643272f 100755
--- a/src/org/unitConverter/unit/BaseUnit.java
+++ b/src/org/unitConverter/unit/BaseUnit.java
@@ -85,6 +85,14 @@ public final class BaseUnit extends LinearUnit {
 	}
 
 	/**
+	 * @return true if the unit is a "full base" unit like the metre or second.
+	 * @since 2019-04-10
+	 */
+	public final boolean isFullBase() {
+		return this.isFullBase;
+	}
+
+	/**
 	 * Returns the product of this unit and another.
 	 * <p>
 	 * Two units can be multiplied if they are part of the same unit system. If {@code multiplier} does not meet this