[fit] 修复校验泛型元素为空时的错误 (#7)

* [fit] 修复校验泛型元素为空时的错误

* [fit] 修改版权

* [fit] 修改检视意见：测试校验注解One -> MinSize

* [fit] 测试校验注解修改为集合最大值上限

---------

Co-authored-by: cherish_li <cherish_li@noreply.gitcode.com>

Author: Cherished-l

framework/fit/java/fit-extension/fit-validation/src/main/java/modelengine/fitframework/validation/ValidationHandler.java

@@ -16,6 +16,7 @@
 import modelengine.fitframework.util.AnnotationUtils;
 import modelengine.fitframework.util.ArrayUtils;
 import modelengine.fitframework.util.CollectionUtils;
+import modelengine.fitframework.util.MapUtils;
 import modelengine.fitframework.util.ObjectUtils;
 import modelengine.fitframework.util.ReflectionUtils;
 import modelengine.fitframework.util.StringUtils;
@@ -172,6 +173,9 @@ private List<ValidationMetadata> getValidationFields(Type validationObject, Obje
     private List<ValidationMetadata> handleCollection(Type[] actualTypeArgs, Collection<?> validationValueCollection,
             Method method, Class<?>[] validationGroups) {
         Validation.equals(actualTypeArgs.length, 1, "The collection must have exactly 1 parameterized type.");
+        if (CollectionUtils.isEmpty(validationValueCollection)) {
+            return Collections.emptyList();
+        }
         return validationValueCollection.stream()
                 .flatMap(element -> this.getValidationFields(actualTypeArgs[0], element, method, validationGroups)
                         .stream())
@@ -181,6 +185,9 @@ private List<ValidationMetadata> handleCollection(Type[] actualTypeArgs, Collect
     private List<ValidationMetadata> handleMap(Type[] actualTypeArgs, Map<?, ?> validationValueMap, Method method,
             Class<?>[] validationGroups) {
         Validation.equals(actualTypeArgs.length, 2, "The map must have exactly 2 parameterized types.");
+        if (MapUtils.isEmpty(validationValueMap)) {
+            return Collections.emptyList();
+        }
         return validationValueMap.entrySet()
                 .stream()
                 .flatMap(entry -> Stream.concat(

framework/fit/java/fit-extension/fit-validation/src/test/java/modelengine/fitframework/validation/ValidationDataControllerTest.java

@@ -1,5 +1,5 @@
 /*---------------------------------------------------------------------------------------------
- *  Copyright (c) 2024 Huawei Technologies Co., Ltd. All rights reserved.
+ *  Copyright (c) 2024-2025 Huawei Technologies Co., Ltd. All rights reserved.
  *  This file is a part of the ModelEngine Project.
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
@@ -23,6 +23,8 @@
 import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collections;
 
 /**
  * {@link ValidationDataController} 的测试集。
@@ -104,4 +106,36 @@ void shouldFailedWhenCreateInvalidProduct() {
         this.response = this.mockMvc.perform(requestBuilder);
         assertThat(this.response.statusCode()).isEqualTo(500);
     }
+
+    @Test
+    @DisplayName("合法 Product-List<Car> 对象校验: cars == null")
+    void shouldOkWhenCreateInvalidProductWithNoCar() {
+        Product product = new Product("mac", 10499.0, 100, "computer", null);
+        MockRequestBuilder requestBuilder =
+                MockMvcRequestBuilders.post("/validation/product/default").jsonEntity(product).responseType(Void.class);
+        this.response = this.mockMvc.perform(requestBuilder);
+        assertThat(this.response.statusCode()).isEqualTo(200);
+    }
+
+    @Test
+    @DisplayName("合法 Product-List<Car> 对象校验: cars.size() == 1")
+    void shouldOkWhenCreateInvalidProductWith1Car() {
+        Car validCar = new Car(1, 1, "brand", "model", 2000, 1999);
+        Product product = new Product("mac", 10499.0, 100, "computer", Collections.singletonList(validCar));
+        MockRequestBuilder requestBuilder =
+                MockMvcRequestBuilders.post("/validation/product/default").jsonEntity(product).responseType(Void.class);
+        this.response = this.mockMvc.perform(requestBuilder);
+        assertThat(this.response.statusCode()).isEqualTo(200);
+    }
+
+    @Test
+    @DisplayName("不合法 Product-List<Car> 对象校验: cars.size() == 2")
+    void shouldFailedWhenCreateInvalidProductWith2Cars() {
+        Car validCar = new Car(1, 1, "brand", "model", 2000, 1999);
+        Product product = new Product("mac", 10499.0, 100, "computer", Arrays.asList(validCar, validCar));
+        MockRequestBuilder requestBuilder =
+                MockMvcRequestBuilders.post("/validation/product/default").jsonEntity(product).responseType(Void.class);
+        this.response = this.mockMvc.perform(requestBuilder);
+        assertThat(this.response.statusCode()).isEqualTo(500);
+    }
 }

framework/fit/java/fit-extension/fit-validation/src/test/java/modelengine/fitframework/validation/annotation/MaxSize.java

@@ -0,0 +1,46 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) 2025 Huawei Technologies Co., Ltd. All rights reserved.
+ *  This file is a part of the ModelEngine Project.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+package modelengine.fitframework.validation.annotation;
+
+import modelengine.fitframework.validation.Validated;
+import modelengine.fitframework.validation.constraints.Constraint;
+import modelengine.fitframework.validation.validator.MaxSizeValidator;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * 表示集合元素数量限制的测试注解类。
+ *
+ * @author 李金绪
+ * @since 2025-03-17
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Constraint({MaxSizeValidator.class})
+@Validated
+public @interface MaxSize {
+    /**
+     * 表示集合元素的大小的上限值。
+     *
+     * @return 表示集合元素的大小的上限值的 {@code long}。
+     */
+    long max();
+
+    /**
+     * 表示校验失败的信息。
+     *
+     * @return 表示校验失败的信息的 {@link String}。
+     */
+    String message() default "must be lesser than the max value.";
+
+    /**
+     * 表示校验的分组。
+     *
+     * @return 表示校验分组的 {@link Class}{@code <?>[]}。
+     */
+    Class<?>[] groups() default {};
+}

framework/fit/java/fit-extension/fit-validation/src/test/java/modelengine/fitframework/validation/data/Product.java

@@ -1,14 +1,17 @@
 /*---------------------------------------------------------------------------------------------
- *  Copyright (c) 2024 Huawei Technologies Co., Ltd. All rights reserved.
+ *  Copyright (c) 2024-2025 Huawei Technologies Co., Ltd. All rights reserved.
  *  This file is a part of the ModelEngine Project.
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
 package modelengine.fitframework.validation.data;
 
+import modelengine.fitframework.validation.annotation.MaxSize;
 import modelengine.fitframework.validation.constraints.NotBlank;
 import modelengine.fitframework.validation.constraints.Positive;
 
+import java.util.List;
+
 /**
  * 表示产品的数据类。
  *
@@ -28,16 +31,43 @@ public class Product {
     @NotBlank(message = "产品类别不能为空")
     private String category;
 
+    @MaxSize(max = 2)
+    private List<Car> cars;
+
     /**
      * Product 默认构造函数。
-     *
      */
     public Product() {}
 
+    /**
+     * 构造函数。
+     *
+     * @param name 表示名字的 {@link String}。
+     * @param price 表示价格的 {@link Double}。
+     * @param quantity 表示数量的 {@link Integer}。
+     * @param category 表示类别的 {@link String}。
+     */
     public Product(String name, Double price, Integer quantity, String category) {
         this.name = name;
         this.price = price;
         this.quantity = quantity;
         this.category = category;
     }
+
+    /**
+     * 构造函数。
+     *
+     * @param name 表示名字的 {@link String}。
+     * @param price 表示价格的 {@link Double}。
+     * @param quantity 表示数量的 {@link Integer}。
+     * @param category 表示类别的 {@link String}。
+     * @param cars 表示汽车集合的 {@link List}{@code <}{@link Car}{@code >}。
+     */
+    public Product(String name, Double price, Integer quantity, String category, List<Car> cars) {
+        this.name = name;
+        this.price = price;
+        this.quantity = quantity;
+        this.category = category;
+        this.cars = cars;
+    }
 }

framework/fit/java/fit-extension/fit-validation/src/test/java/modelengine/fitframework/validation/validator/MaxSizeValidator.java

@@ -0,0 +1,41 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) 2025 Huawei Technologies Co., Ltd. All rights reserved.
+ *  This file is a part of the ModelEngine Project.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+package modelengine.fitframework.validation.validator;
+
+import static modelengine.fitframework.util.ObjectUtils.cast;
+
+import modelengine.fitframework.validation.ConstraintValidator;
+import modelengine.fitframework.validation.annotation.MaxSize;
+
+import java.util.List;
+
+/**
+ * 表示单集合元素的测试校验类。
+ *
+ * @author 李金绪
+ * @since 2025-03-17
+ */
+public class MaxSizeValidator implements ConstraintValidator<MaxSize, Object> {
+    private long max;
+
+    @Override
+    public void initialize(MaxSize constraintAnnotation) {
+        this.max = constraintAnnotation.max();
+    }
+
+    @Override
+    public boolean isValid(Object value) {
+        if (value == null) {
+            return true;
+        }
+        if (!(value instanceof List)) {
+            return false;
+        }
+        List<Object> valueList = cast(value);
+        return valueList.size() < this.max;
+    }
+}