Introduce Applicative Validation

scripts/generate-applicative.sh

@@ -0,0 +1,176 @@
+#!/bin/bash
+set -e
+n=10
+
+for i in `seq 1 ${n}`;do
+  class="Function${i}"
+  file="$(dirname $0)/../src/main/java/am/ik/yavi/fn/${class}.java"
+  echo $file
+  cat <<EOF > ${file}
+/*
+ * Copyright (C) 2018-2021 Toshiaki Maki <makingx@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package am.ik.yavi.fn;
+
+/**
+ * Generated by
+ * https://github.com/making/yavi/blob/develop/scripts/generate-applicative.sh
+ *
+ * @since 0.6.0
+ */
+public interface ${class}<$(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done) | sed 's/,$//'), R> {
+
+	R apply($(echo $(for j in `seq 1 ${i}`;do echo -n "T${j} t${j}, ";done) | sed 's/,$//'));
+}
+EOF
+done
+
+for i in `seq 1 ${n}`;do
+  class="Composing${i}"
+  file="$(dirname $0)/../src/main/java/am/ik/yavi/fn/${class}.java"
+  echo $file
+  cat <<EOF > ${file}
+/*
+ * Copyright (C) 2018-2021 Toshiaki Maki <makingx@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package am.ik.yavi.fn;
+
+import java.util.List;
+
+/**
+ * Generated by
+ * https://github.com/making/yavi/blob/develop/scripts/generate-applicative.sh
+ *
+ * @since 0.6.0
+ */
+public class ${class}<E, $(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done) | sed 's/,$//')> {
+$(for j in `seq 1 ${i}`;do echo "	protected final Validation<E, T${j}> v${j};";echo;done)
+
+	public ${class}($(echo $(for j in `seq 1 ${i}`;do echo -n "Validation<E, T${j}> v${j}, ";done) | sed 's/,$//')) {
+$(for j in `seq 1 ${i}`;do echo "		this.v${j} = v${j};";done)
+	}
+
+	public <R> Validation<E, R> apply(Function${i}<$(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done) | sed 's/,$//'), R> f) {
+		return $(echo $(for j in `seq ${i} 1`;do echo -n "v${j}.apply(";done) | sed 's/,$//')Validation.success(Functions.curry(f))$(echo $(for j in `seq 1 ${i}`;do echo -n ")";done));
+	}
+$(if [ ${i} -lt ${n} ];then echo;echo "	public <T$((${i} + 1))> Composing$((${i} + 1))<E, $(echo $(for j in `seq 1 $((${i} + 1))`;do echo -n "T${j}, ";done) | sed 's/,$//')> compose(Validation<E, T$((${i} + 1))> v$((${i} + 1))) {"; echo "		return new Composing$((${i} + 1))<>($(echo $(for j in `seq 1 $((${i} + 1))`;do echo -n "v${j}, ";done) | sed 's/,$//'));"; echo "	}"; else echo -n "";fi)
+}
+EOF
+done
+
+class="Validations"
+file="$(dirname $0)/../src/main/java/am/ik/yavi/fn/${class}.java"
+echo $file
+cat <<EOF > ${file}
+/*
+ * Copyright (C) 2018-2021 Toshiaki Maki <makingx@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package am.ik.yavi.fn;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
+
+/**
+ * Generated by
+ * https://github.com/making/yavi/blob/develop/scripts/generate-applicative.sh
+ *
+ * @since 0.6.0
+ */
+public class ${class} {
+$(for i in `seq 1 ${n}`;do echo "	public static <E, $(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done) | sed 's/,$//')> Composing${i}<E, $(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done) | sed 's/,$//')> compose($(echo $(for j in `seq 1 ${i}`;do echo -n "Validation<E, T${j}> v${j}, ";done) | sed 's/,$//')) {"; echo "		return new Composing${i}<>($(echo $(for j in `seq 1 ${i}`;do echo -n "v${j}, ";done) | sed 's/,$//'));"; echo "	}";echo;done)
+
+$(for i in `seq 1 ${n}`;do echo "	public static <R, E, $(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done) | sed 's/,$//')> Validation<E, R> apply(Function${i}<$(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done) | sed 's/,$//'), R> f, $(echo $(for j in `seq 1 ${i}`;do echo -n "Validation<E, T${j}> v${j}, ";done) | sed 's/,$//')) {"; echo "		return compose($(echo $(for j in `seq 1 ${i}`;do echo -n "v${j}, ";done) | sed 's/,$//')).apply(f);"; echo "	}";echo;done)
+
+	public static <E, T> Validation<E, List<T>> sequence(
+			Iterable<Validation<E, T>> validations) {
+		final List<E> errors = new ArrayList<>();
+		final List<T> values = new ArrayList<>();
+		for (Validation<E, T> validation : validations) {
+			if (!validation.isValid()) {
+				errors.addAll(validation.errors());
+			}
+			else if (errors.isEmpty()) {
+				values.add(validation.value());
+			}
+		}
+		return errors.isEmpty() ? Validation.success(values) : Validation.failure(errors);
+	}
+
+	public static <E, T, U> Validation<E, List<U>> traverse(Iterable<T> values,
+			Function<T, Validation<E, U>> mapper) {
+		return sequence(StreamSupport.stream(values.spliterator(), false).map(mapper)
+				.collect(Collectors.toList()));
+	}
+}
+EOF
+
+class="Functions"
+file="$(dirname $0)/../src/main/java/am/ik/yavi/fn/${class}.java"
+echo $file
+cat <<EOF > ${file}
+/*
+ * Copyright (C) 2018-2021 Toshiaki Maki <makingx@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package am.ik.yavi.fn;
+
+/**
+ * Generated by
+ * https://github.com/making/yavi/blob/develop/scripts/generate-applicative.sh
+ *
+ * @since 0.6.0
+ */
+public class ${class} {
+$(for i in `seq 1 ${n}`;do echo "	public static <$(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done)) R> $(echo $(for j in `seq 1 ${i}`;do echo -n "Function1<T${j}, ";done)) R$(echo $(for j in `seq 1 ${i}`;do echo -n ">";done)) curry(Function${i}<$(echo $(for j in `seq 1 ${i}`;do echo -n "T${j}, ";done)) R> f) {"; echo "		return $(echo $(for j in `seq 1 ${i}`;do echo -n "t${j} -> ";done)) f.apply($(echo $(for j in `seq 1 ${i}`;do echo -n "t${j}, ";done) | sed 's/,$//'));"; echo "	}";echo;done)
+}
+EOF

src/main/java/am/ik/yavi/builder/ValidatorBuilder.java

@@ -764,7 +764,7 @@ private <N> Consumer<Pair<ConstraintCondition<N>, ValidatorSubset<N>>> appendNes
 			final ConstraintCondition<T> condition = new NestedConstraintCondition<>(
 					nested, conditionalValidator.first());
 			final ValidatorSubset<T> v = new NestedValidatorSubset<>(nested,
-					conditionalValidator.second(), name + this.messageKeySeparator);
+					conditionalValidator.second(), name);
 			this.conditionalValidators.add(new Pair<>(condition, v));
 		};
 	}

src/main/java/am/ik/yavi/core/ApplicativeValidator.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2018-2021 Toshiaki Maki <makingx@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package am.ik.yavi.core;
+
+import java.util.Locale;
+
+import am.ik.yavi.fn.Validation;
+
+/**
+ * Applicative validator class
+ * @param <T> Target class
+ * @since 0.6.0
+ */
+public final class ApplicativeValidator<T> {
+	private final Validator<T> validator;
+
+	ApplicativeValidator(Validator<T> validator) {
+		this.validator = validator;
+	}
+
+	public Validation<ConstraintViolation, T> validate(T target) {
+		return this.validate(target, Locale.getDefault(), ConstraintGroup.DEFAULT);
+	}
+
+	public Validation<ConstraintViolation, T> validate(T target, Locale locale,
+			ConstraintGroup constraintGroup) {
+		final ConstraintViolations violations = this.validator.validate(target, locale,
+				constraintGroup);
+		if (violations.isValid()) {
+			return Validation.success(target);
+		}
+		else {
+			return Validation.failure(violations);
+		}
+	}
+}

src/main/java/am/ik/yavi/core/ConstraintViolations.java

@@ -26,7 +26,37 @@
 import java.util.stream.Collectors;
 
 public class ConstraintViolations implements List<ConstraintViolation> {
-	private final List<ConstraintViolation> delegate = new ArrayList<>();
+	private final List<ConstraintViolation> delegate;
+
+	/**
+	 * Constructs with the constraintViolations to delegate. If the given value is
+	 * <code>ConstraintViolations</code> itself, cast and return it.
+	 *
+	 * @param delegate constraintViolations to delegate
+	 * @since 0.6.0
+	 */
+	public static ConstraintViolations of(List<ConstraintViolation> delegate) {
+		if (delegate instanceof ConstraintViolations) {
+			return (ConstraintViolations) delegate;
+		}
+		return new ConstraintViolations(delegate);
+	}
+
+	/**
+	 * Constructs an empty list with an initial capacity of ten.
+	 */
+	public ConstraintViolations() {
+		this.delegate = new ArrayList<>();
+	}
+
+	/**
+	 * Constructs with the constraintViolations to delegate
+	 * @param delegate constraintViolations to delegate
+	 * @since 0.6.0
+	 */
+	public ConstraintViolations(List<ConstraintViolation> delegate) {
+		this.delegate = delegate;
+	}
 
 	/**
 	 * Appends the specified element to the end of this list (optional operation).

src/main/java/am/ik/yavi/core/Validator.java

@@ -28,9 +28,9 @@
 
 /**
  * Validates the target instances.
- * 
+ *
  * A <code>Validator</code> instance is immutable and can be used as a singleton.
- * 
+ *
  * @param <T> the type of the instance to validate
  * @author Toshiaki Maki
  */
@@ -67,18 +67,20 @@ private Validator(String messageKeySeparator,
 		this.collectionValidators = collectionValidators;
 		this.conditionalValidators = conditionalValidators;
 		this.messageFormatter = messageFormatter;
-		this.prefix = prefix;
+		this.prefix = (prefix == null || prefix.isEmpty()
+				|| prefix.endsWith(this.messageKeySeparator)) ? prefix
+						: prefix + this.messageKeySeparator;
 	}
 
-	Validator<T> prefixed(String prefix) {
+	public Validator<T> prefixed(String prefix) {
 		return new Validator<>(this.messageKeySeparator, this.predicatesList,
 				this.collectionValidators, this.conditionalValidators,
 				this.messageFormatter, prefix);
 	}
 
 	/**
 	 * This method is supposed to be used only internally.
-	 * 
+	 *
 	 * @param action callback per <code>ConstraintPredicates</code>.
 	 */
 	public void forEachPredicates(Consumer<ConstraintPredicates<T, ?>> action) {
@@ -121,7 +123,7 @@ public ConstraintViolations validate(T target, ConstraintGroup constraintGroup)
 	/**
 	 * Validates all constraints on {@code target}.<br>
 	 * {@code ConstraintGroup.DEFAULT} is used as a constraint group.
-	 * 
+	 *
 	 * @param target target to validate
 	 * @param locale the locale targeted for the violation messages.
 	 * @return constraint violations
@@ -158,6 +160,15 @@ public ConstraintViolations validate(T target) {
 		return this.validate(target, Locale.getDefault(), ConstraintGroup.DEFAULT);
 	}
 
+	/**
+	 * Convert to the applicative validator
+	 * @return applicative validator
+	 * @since 0.6.0
+	 */
+	public ApplicativeValidator<T> applicative() {
+		return new ApplicativeValidator<>(this);
+	}
+
 	/**
 	 * Validates all constraints on {@code target} and returns {@code Either} object that
 	 * has constraint violations on the left or validated object on the right. <br>

src/main/java/am/ik/yavi/fn/Composing1.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2018-2021 Toshiaki Maki <makingx@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package am.ik.yavi.fn;
+
+import java.util.List;
+
+/**
+ * Generated by
+ * https://github.com/making/yavi/blob/develop/scripts/generate-applicative.sh
+ *
+ * @since 0.6.0
+ */
+public class Composing1<E, T1> {
+	protected final Validation<E, T1> v1;
+
+	public Composing1(Validation<E, T1> v1) {
+		this.v1 = v1;
+	}
+
+	public <R> Validation<E, R> apply(Function1<T1, R> f) {
+		return v1.apply(Validation.success(Functions.curry(f)));
+	}
+
+	public <T2> Composing2<E, T1, T2> compose(Validation<E, T2> v2) {
+		return new Composing2<>(v1, v2);
+	}
+}