#43 Implemented support for throwable functions for Option.map/flatMap

Author: pnerg

src/main/java/javascalautils/BrokenFunctionException.java

@@ -0,0 +1,20 @@
+package javascalautils;
+
+/**
+ * Used when a function throws an exception which cannot be raised. <br>
+ * This exception is then created and wrapped around the original exception.
+ * @author Peter Nerg
+ * @since 1.11
+ */
+public final class BrokenFunctionException extends RuntimeException {
+    private static final long serialVersionUID = 3534543534523L;
+    /**
+     * Creates the exception
+     * @param message The message
+     * @param cause The underlying cause
+     */
+    public BrokenFunctionException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+}

src/main/java/javascalautils/None.java

@@ -17,7 +17,6 @@
 
 import java.io.Serializable;
 import java.util.NoSuchElementException;
-import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
 
@@ -81,7 +80,7 @@ public boolean exists(Predicate<T> predicate) {
      * @since 1.0
      */
     @SuppressWarnings("unchecked")
-    public <R> Option<R> map(Function<T, R> function) {
+    public <R> Option<R> map(ThrowableFunction1<T, R> function) {
         return (Option<R>) this;
     }
 
@@ -93,7 +92,7 @@ public <R> Option<R> map(Function<T, R> function) {
      * @since 1.0
      */
     @Override
-    public <R> Option<R> flatMap(Function<T, Option<R>> function) {
+    public <R> Option<R> flatMap(ThrowableFunction1<T, Option<R>> function) {
         // uses the Map method as it anyways produces the same result
         return map(null);
     }

src/main/java/javascalautils/Option.java

@@ -18,7 +18,6 @@
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Optional;
-import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
 import java.util.stream.Stream;
@@ -275,7 +274,7 @@ default boolean isEmpty() {
      * @return The Option containing the mapped value
      * @since 1.0
      */
-    <R> Option<R> map(Function<T, R> function);
+    <R> Option<R> map(ThrowableFunction1<T, R> function);
 
     /**
      * Returns an Option consisting of the result of applying the given function to the current {@link Some}. <br>
@@ -288,7 +287,7 @@ default boolean isEmpty() {
      * @return The Option containing the mapped value
      * @since 1.2
      */
-    <R> Option<R> flatMap(Function<T, Option<R>> function);
+    <R> Option<R> flatMap(ThrowableFunction1<T, Option<R>> function);
 
     /**
      * Returns this Option if it is nonempty, otherwise return the result of provided by the supplier.

src/main/java/javascalautils/Some.java

@@ -93,8 +93,8 @@ public T getOrElse(Supplier<T> s) {
      * @since 1.0
      */
     @Override
-    public <R> Option<R> map(Function<T, R> f) {
-        return Option.apply(f.apply(value));
+    public <R> Option<R> map(ThrowableFunction1<T, R> f) {
+        return flatMap(v -> Option.apply(f.apply(v)));
     }
 
     /**
@@ -103,8 +103,13 @@ public <R> Option<R> map(Function<T, R> f) {
      * @since 1.2
      */
     @Override
-    public <R> Option<R> flatMap(Function<T, Option<R>> function) {
-        return function.apply(value);
+    public <R> Option<R> flatMap(ThrowableFunction1<T, Option<R>> function) {
+        try {
+            return function.apply(value);
+        }
+        catch (Throwable ex) {
+            throw new BrokenFunctionException("Caught exception while applying function", ex);
+        }
     }
 
     /**