Add Result.tryMap (#33)

Signed-off-by: David Greven <[email protected]> Signed-off-by: Sebastian Becker <[email protected]>
carbynestack · Dec 13, 2021 · 9da9521 · 9da9521
1 parent 46149c8
commit 9da9521
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Showing 10 changed files with 214 additions and 12 deletions.
diff --git a/common-testing/3RD-PARTY-LICENSES/sbom.xml b/common-testing/3RD-PARTY-LICENSES/sbom.xml
@@ -17,7 +17,7 @@
          <name>common-types</name>
          <groupId>io.carbynestack</groupId>
          <artifactId>common-types</artifactId>
-         <version>0.1-SNAPSHOT</version>
+         <version>0.2-SNAPSHOT</version>
          <licenses>
             <license>
                <name>Apache-2.0</name>

diff --git a/common-testing/src/test/java/io/carbynestack/common/result/FailureTest.java b/common-testing/src/test/java/io/carbynestack/common/result/FailureTest.java
@@ -58,6 +58,30 @@ void mapAndTransformType() {
                 .hasReason(reason);
     }
 
+    @Test
+    void tryMap() {
+        assertThat(result.tryMap(v -> v * 2, reason * 2)).hasReason(reason);
+    }
+
+    @Test
+    void tryMapNullPointerException() {
+        assertThatThrownBy(() -> result.tryMap(null, reason * 2))
+                .isExactlyInstanceOf(NullPointerException.class);
+    }
+
+    @Test
+    void tryMapAndTransformType() {
+        assertThat(result.tryMap(v -> String.format("%s * 2 -> %s", v, v * 2),
+                reason * 2)).hasReason(reason);
+    }
+
+    @Test
+    void tryMapWithException() {
+        assertThat(result.tryMap(v -> {
+            throw new IOException("-11");
+        }, reason * 2)).hasReason(reason);
+    }
+
     @Test
     void peek() {
         AtomicInteger output = new AtomicInteger(-1);
@@ -80,11 +104,9 @@ void tryPeek() {
 
     @Test
     void tryPeekWithException() {
-        Result<Integer, Integer> res = result.tryPeek(v -> {
+        assertThat(result.tryPeek(v -> {
             throw new IOException("-11");
-        }, reason * 2);
-        assertThat(res).isFailure();
-        assertThat(res).hasReason(reason);
+        }, reason * 2)).hasReason(reason);
     }
 
     @Test

diff --git a/common-testing/src/test/java/io/carbynestack/common/result/SuccessTest.java b/common-testing/src/test/java/io/carbynestack/common/result/SuccessTest.java
@@ -59,6 +59,31 @@ void mapAndTransformType() {
                 .hasValue("12 * 2 -> 24");
     }
 
+    @Test
+    void tryMap() {
+        assertThat(result.tryMap(v -> v * 2, -11)).hasValue(24);
+    }
+
+    @Test
+    void tryMapNullPointerException() {
+        assertThatThrownBy(() -> result.tryMap(null, -11))
+                .isExactlyInstanceOf(NullPointerException.class);
+    }
+
+    @Test
+    void tryMapAndTransformType() {
+        assertThat(result.tryMap(v -> String.format("%s * 2 -> %s", v, v * 2),
+                -11)).hasValue("12 * 2 -> 24");
+    }
+
+    @Test
+    void tryMapWithException() {
+        int reason = -11;
+        assertThat(result.tryMap(v -> {
+            throw new IOException("-11");
+        }, reason)).hasReason(reason);
+    }
+
     @Test
     void peek() {
         AtomicInteger output = new AtomicInteger(-1);
@@ -82,11 +107,9 @@ void tryPeek() {
     @Test
     void tryPeekWithException() {
         int reason = -11;
-        Result<Integer, Integer> res = result.tryPeek(v -> {
+        assertThat(result.tryPeek(v -> {
             throw new IOException("-11");
-        }, reason);
-        assertThat(res).isFailure();
-        assertThat(res).hasReason(reason);
+        }, reason)).hasReason(reason);
     }
 
     @Test

diff --git a/common-types/src/main/java/io/carbynestack/common/result/Failure.java b/common-types/src/main/java/io/carbynestack/common/result/Failure.java
@@ -8,6 +8,7 @@
 
 import io.carbynestack.common.Generated;
 import io.carbynestack.common.function.AnyThrowingConsumer;
+import io.carbynestack.common.function.AnyThrowingFunction;
 
 import java.util.Objects;
 import java.util.Optional;
@@ -89,6 +90,28 @@ public <N> Result<N, F> map(Function<? super S, ? super N> function) {
         return new Failure<>(this.reason());
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @param function the mapping function to apply to a {@link Success#value()}
+     * @param reason   the failure reason in case of the function throwing
+     *                 a {@code Throwable}
+     * @param <N>      the success type of the value returned from the mapping
+     *                 function
+     * @return the {@code Result} of mapping the given function to the value
+     * from this {@link Success} or this {@link Failure}
+     * @throws NullPointerException if the mapping function is {@code null}
+     * @version JDK 8
+     * @see #recover(Function)
+     * @see #peek(Consumer)
+     * @since 0.2.0
+     */
+    @Override
+    public <N> Result<N, F> tryMap(AnyThrowingFunction<? super S, ? super N> function, F reason) {
+        requireNonNull(function);
+        return new Failure<>(this.reason());
+    }
+
     /**
      * {@inheritDoc}
      *
@@ -272,9 +295,7 @@ public Stream<S> stream() {
     @Override
     @Generated
     public String toString() {
-        return "Failure{" +
-                "reason=" + reason +
-                '}';
+        return "Failure{" + "reason=" + reason + '}';
     }
 
     @Override

diff --git a/common-types/src/main/java/io/carbynestack/common/result/Result.java b/common-types/src/main/java/io/carbynestack/common/result/Result.java
@@ -8,6 +8,7 @@
 
 import io.carbynestack.common.CsFailureReason;
 import io.carbynestack.common.function.AnyThrowingConsumer;
+import io.carbynestack.common.function.AnyThrowingFunction;
 import io.carbynestack.common.function.AnyThrowingSupplier;
 import io.carbynestack.common.function.ThrowingSupplier;
 
@@ -159,6 +160,28 @@ default boolean isFailure() {
      */
     <N> Result<N, F> map(Function<? super S, ? super N> function);
 
+    /**
+     * If the {@code Result} is a {@link Success}, returns the result of
+     * applying the given mapping function to the {@link Success#value()}.
+     * Otherwise, a cast version of the {@link Failure} is returned.
+     *
+     * <p>In case the function throws a {@link Throwable} the failure reason
+     * is returned as a {@code Failure}.<br>
+     *
+     * @param function the mapping function to apply to a {@link Success#value()}
+     * @param reason   the failure reason in case of the function throwing
+     *                 a {@code Throwable}
+     * @param <N>      the success type of the value returned from the mapping
+     *                 function
+     * @return the {@code Result} of mapping the given function to the value
+     * from this {@link Success} or this {@link Failure}
+     * @throws NullPointerException if the mapping function is {@code null}
+     * @see #recover(Function)
+     * @see #peek(Consumer)
+     * @since 0.2.0
+     */
+    <N> Result<N, F> tryMap(AnyThrowingFunction<? super S, ? super N> function, F reason);
+
     /**
      * If the {@code Result} is a {@link Success}, invokes the provided
      * consumer with the {@link Success#value()}. Otherwise, the

diff --git a/common-types/src/main/java/io/carbynestack/common/result/Success.java b/common-types/src/main/java/io/carbynestack/common/result/Success.java
@@ -8,6 +8,7 @@
 
 import io.carbynestack.common.Generated;
 import io.carbynestack.common.function.AnyThrowingConsumer;
+import io.carbynestack.common.function.AnyThrowingFunction;
 
 import java.util.Objects;
 import java.util.Optional;
@@ -90,6 +91,33 @@ public <N> Result<N, F> map(Function<? super S, ? super N> function) {
         return new Success<>((N) function.apply(this.value()));
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @param function the mapping function to apply to a {@link Success#value()}
+     * @param reason   the failure reason in case of the function throwing
+     *                 a {@code Throwable}
+     * @param <N>      the success type of the value returned from the mapping
+     *                 function
+     * @return the {@code Result} of mapping the given function to the value
+     * from this {@link Success} or this {@link Failure}
+     * @throws NullPointerException if the mapping function is {@code null}
+     * @version JDK 8
+     * @see #recover(Function)
+     * @see #peek(Consumer)
+     * @since 0.2.0
+     */
+    @Override
+    @SuppressWarnings("unchecked")
+    public <N> Result<N, F> tryMap(AnyThrowingFunction<? super S, ? super N> function, F reason) {
+        requireNonNull(function);
+        try {
+            return new Success<>((N) function.apply(this.value()));
+        } catch (Throwable throwable) {
+            return new Failure<>(reason);
+        }
+    }
+
     /**
      * {@inheritDoc}
      *

diff --git a/common-types/src/main/java17/io/carbynestack/common/result/Failure.java b/common-types/src/main/java17/io/carbynestack/common/result/Failure.java
@@ -7,6 +7,7 @@
 package io.carbynestack.common.result;
 
 import io.carbynestack.common.function.AnyThrowingConsumer;
+import io.carbynestack.common.function.AnyThrowingFunction;
 
 import java.util.Optional;
 import java.util.function.Consumer;
@@ -60,6 +61,28 @@ public <N> Result<N, F> map(Function<? super S, ? super N> function) {
         return new Failure<>(this.reason());
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @param function the mapping function to apply to a {@link Success#value()}
+     * @param reason   the failure reason in case of the function throwing
+     *                 a {@code Throwable}
+     * @param <N>      the success type of the value returned from the mapping
+     *                 function
+     * @return the {@code Result} of mapping the given function to the value
+     * from this {@link Success} or this {@link Failure}
+     * @throws NullPointerException if the mapping function is {@code null}
+     * @version JDK 17
+     * @see #recover(Function)
+     * @see #peek(Consumer)
+     * @since 0.2.0
+     */
+    @Override
+    public <N> Result<N, F> tryMap(AnyThrowingFunction<? super S, ? super N> function, F reason) {
+        requireNonNull(function);
+        return new Failure<>(this.reason());
+    }
+
     /**
      * {@inheritDoc}
      *

diff --git a/common-types/src/main/java17/io/carbynestack/common/result/Result.java b/common-types/src/main/java17/io/carbynestack/common/result/Result.java
@@ -9,6 +9,7 @@
 import io.carbynestack.common.CsFailureReason;
 import io.carbynestack.common.function.AnyThrowingConsumer;
 import io.carbynestack.common.function.AnyThrowingSupplier;
+import io.carbynestack.common.function.AnyThrowingFunction;
 import io.carbynestack.common.function.ThrowingSupplier;
 
 import java.util.Map;
@@ -159,6 +160,28 @@ default boolean isFailure() {
      */
     <N> Result<N, F> map(Function<? super S, ? super N> function);
 
+    /**
+     * If the {@code Result} is a {@link Success}, returns the result of
+     * applying the given mapping function to the {@link Success#value()}.
+     * Otherwise, a cast version of the {@link Failure} is returned.
+     *
+     * <p>In case the function throws a {@link Throwable} the failure reason
+     * is returned as a {@code Failure}.<br>
+     *
+     * @param function the mapping function to apply to a {@link Success#value()}
+     * @param reason   the failure reason in case of the function throwing
+     *                 a {@code Throwable}
+     * @param <N>      the success type of the value returned from the mapping
+     *                 function
+     * @return the {@code Result} of mapping the given function to the value
+     * from this {@link Success} or this {@link Failure}
+     * @throws NullPointerException if the mapping function is {@code null}
+     * @see #recover(Function)
+     * @see #peek(Consumer)
+     * @since 0.2.0
+     */
+    <N> Result<N, F> tryMap(AnyThrowingFunction<? super S, ? super N> function, F reason);
+
     /**
      * If the {@code Result} is a {@link Success}, invokes the provided
      * consumer with the {@link Success#value()}. Otherwise, the

diff --git a/common-types/src/main/java17/io/carbynestack/common/result/Success.java b/common-types/src/main/java17/io/carbynestack/common/result/Success.java
@@ -7,6 +7,7 @@
 package io.carbynestack.common.result;
 
 import io.carbynestack.common.function.AnyThrowingConsumer;
+import io.carbynestack.common.function.AnyThrowingFunction;
 
 import java.util.Optional;
 import java.util.function.Consumer;
@@ -61,6 +62,33 @@ public <N> Result<N, F> map(Function<? super S, ? super N> function) {
         return new Success<>((N) function.apply(this.value()));
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @param function the mapping function to apply to a {@link Success#value()}
+     * @param reason   the failure reason in case of the function throwing
+     *                 a {@code Throwable}
+     * @param <N>      the success type of the value returned from the mapping
+     *                 function
+     * @return the {@code Result} of mapping the given function to the value
+     * from this {@link Success} or this {@link Failure}
+     * @throws NullPointerException if the mapping function is {@code null}
+     * @version JDK 17
+     * @see #recover(Function)
+     * @see #peek(Consumer)
+     * @since 0.2.0
+     */
+    @Override
+    @SuppressWarnings("unchecked")
+    public <N> Result<N, F> tryMap(AnyThrowingFunction<? super S, ? super N> function, F reason) {
+        requireNonNull(function);
+        try {
+            return new Success<>((N) function.apply(this.value()));
+        } catch (Throwable throwable) {
+            return new Failure<>(reason);
+        }
+    }
+
     /**
      * {@inheritDoc}
      *

diff --git a/common-types/src/test/java/io/carbynestack/common/result/ResultTest.java b/common-types/src/test/java/io/carbynestack/common/result/ResultTest.java
@@ -88,6 +88,17 @@ void tryPeek() {
                 .isFailure()).isTrue();
     }
 
+    @Test
+    void tryMap() {
+        assertThat(new Success<>(12)
+                .tryMap(v -> v * 2, -11)
+                .<Integer>tryMap(v -> {
+                    throw new RuntimeException();
+                }, -21)
+                .tryMap(v -> v * 2, -11)
+                .isFailure()).isTrue();
+    }
+
     @Test
     void of() {
         var value = 12;