Move exceptions to their own package and subclass one class.

core/src/main/java/org/nwapw/abacus/exception/AbacusException.java

@@ -0,0 +1,9 @@
+package org.nwapw.abacus.exception;
+
+public class AbacusException extends RuntimeException {
+
+    public AbacusException(String baseMessage, String description){
+        super(baseMessage + ((description == null) ? "." : (": " + description)));
+    }
+
+}

core/src/main/java/org/nwapw/abacus/exception/ComputationInterruptedException.java

@@ -1,16 +1,16 @@
-package org.nwapw.abacus.number;
+package org.nwapw.abacus.exception;
 
 /**
  * Exception thrown when the computation is interrupted by
  * the user.
  */
-public class ComputationInterruptedException extends RuntimeException {
+public class ComputationInterruptedException extends AbacusException {
 
     /**
      * Creates a new exception of this type.
      */
     public ComputationInterruptedException() {
-        super("Computation interrupted.");
+        super("Computation interrupted", null);
     }
 
 }

core/src/main/java/org/nwapw/abacus/exception/DomainException.java

@@ -1,24 +1,24 @@
-package org.nwapw.abacus.function;
+package org.nwapw.abacus.exception;
 
 /**
  * Exception thrown if the function parameters do not match
  * requirements.
  */
-public class DomainException extends RuntimeException {
+public class DomainException extends AbacusException {
 
     /**
      * Creates a new DomainException.
      * @param reason the reason for which the exception is thrown.
      */
     public DomainException(String reason) {
-        super(reason);
+        super("Domain error", reason);
     }
 
     /**
      * Creates a new DomainException with a default message.
      */
     public DomainException(){
-        this("Domain error.");
+        this(null);
     }
 
 }

core/src/main/java/org/nwapw/abacus/exception/EvaluationException.java

@@ -1,17 +1,17 @@
-package org.nwapw.abacus.function;
+package org.nwapw.abacus.exception;
 
 /**
  * An exception thrown primarily from Tree Value operators and functions,
  * which have to deal with the result of a Reducer as well as the results
  * of Applicable.
  */
-public class EvaluationException extends RuntimeException {
+public class EvaluationException extends AbacusException {
 
     /**
      * Creates a new EvaluationException with the default string.
      */
     public EvaluationException() {
-        super("Evaluation error.");
+        this(null);
     }
 
     /**
@@ -19,7 +19,7 @@ public class EvaluationException extends RuntimeException {
      * @param message the message string.
      */
     public EvaluationException(String message) {
-        super(message);
+        super("Evaluation error", message);
     }
 
 }

core/src/main/java/org/nwapw/abacus/number/NumberInterface.java

@@ -1,5 +1,7 @@
 package org.nwapw.abacus.number;
 
+import org.nwapw.abacus.exception.ComputationInterruptedException;
+
 /**
  * An interface used to represent a number.
  */

core/src/main/kotlin/org/nwapw/abacus/function/applicable/Applicable.kt

@@ -1,7 +1,7 @@
 package org.nwapw.abacus.function.applicable
 
 import org.nwapw.abacus.context.MutableEvaluationContext
-import org.nwapw.abacus.function.DomainException
+import org.nwapw.abacus.exception.DomainException
 
 /**
  * A class that can be applied to arguments.

core/src/main/kotlin/org/nwapw/abacus/tree/NumberReducer.kt

@@ -2,7 +2,7 @@ package org.nwapw.abacus.tree
 
 import org.nwapw.abacus.Abacus
 import org.nwapw.abacus.context.EvaluationContext
-import org.nwapw.abacus.function.EvaluationException
+import org.nwapw.abacus.exception.EvaluationException
 import org.nwapw.abacus.number.NumberInterface
 
 class NumberReducer(val abacus: Abacus, context: EvaluationContext) : Reducer<NumberInterface> {

core/src/test/java/org/nwapw/abacus/tests/CalculationTests.java

@@ -5,7 +5,7 @@ import org.junit.BeforeClass;
 import org.junit.Test;
 import org.nwapw.abacus.Abacus;
 import org.nwapw.abacus.config.Configuration;
-import org.nwapw.abacus.function.DomainException;
+import org.nwapw.abacus.exception.DomainException;
 import org.nwapw.abacus.number.NumberInterface;
 import org.nwapw.abacus.plugin.StandardPlugin;
 import org.nwapw.abacus.tree.TreeNode;

fx/src/main/java/org/nwapw/abacus/fx/AbacusController.java

@@ -12,10 +12,11 @@ import javafx.util.Callback;
 import javafx.util.StringConverter;
 import org.nwapw.abacus.Abacus;
 import org.nwapw.abacus.config.Configuration;
+import org.nwapw.abacus.exception.ComputationInterruptedException;
 import org.nwapw.abacus.function.Documentation;
 import org.nwapw.abacus.function.DocumentationType;
-import org.nwapw.abacus.function.DomainException;
-import org.nwapw.abacus.function.EvaluationException;
+import org.nwapw.abacus.exception.DomainException;
+import org.nwapw.abacus.exception.EvaluationException;
 import org.nwapw.abacus.number.*;
 import org.nwapw.abacus.plugin.ClassFinder;
 import org.nwapw.abacus.plugin.PluginListener;