refactor!: BasePropertyValidator 的 equalsThat 重命名为 equalTo

通过自定义函数式接口，使 lambda 表达式作为入参时，可以进入不同的重载版本，从而返回不同类型属性的校验器。

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/BasePropertyValidator.java

@@ -122,31 +122,31 @@ public abstract class BasePropertyValidator<T, TProperty, TPropertyValidator ext
     // ================================
 
     // ================================
-    // #region - equals
+    // #region - equalTo
     // ================================
 
-    public TPropertyValidator equalsThat(Object that) {
-        return equalsThat(that,
+    public TPropertyValidator equalTo(Object that) {
+        return equalTo(that,
                 value -> new IllegalArgumentException(String.format("The input must be equal to '%s'.", that)));
     }
 
-    public TPropertyValidator equalsThat(Object that, String errMsg) {
-        return equalsThat(that, convertExceptionCreator(errMsg));
+    public TPropertyValidator equalTo(Object that, String errMsg) {
+        return equalTo(that, convertExceptionCreator(errMsg));
     }
 
-    public <E extends RuntimeException> TPropertyValidator equalsThat(
+    public <E extends RuntimeException> TPropertyValidator equalTo(
             Object that, Supplier<E> exceptionCreator) {
-        return equalsThat(that, convertExceptionCreator(exceptionCreator));
+        return equalTo(that, convertExceptionCreator(exceptionCreator));
     }
 
-    public <E extends RuntimeException> TPropertyValidator equalsThat(
+    public <E extends RuntimeException> TPropertyValidator equalTo(
             Object that, Function<TProperty, E> exceptionCreator) {
         withRule(value -> Objects.equals(value, that), exceptionCreator);
         return thisObject();
     }
 
     // ================================
-    // #endregion - equals
+    // #endregion - equalTo
     // ================================
 
     // ================================

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/BaseValidator.java

@@ -24,6 +24,8 @@ import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
 
+import xyz.zhouxy.plusone.validator.function.*;
+
 /**
  * BaseValidator
  *
@@ -79,30 +81,60 @@ public abstract class BaseValidator<T> {
         return validator;
     }
 
+    protected final IntPropertyValidator<T> ruleFor(ToIntegerFunction<T> getter) {
+        IntPropertyValidator<T> validator = new IntPropertyValidator<>(getter);
+        this.rules.add(validator::validate);
+        return validator;
+    }
+
     protected final LongPropertyValidator<T> ruleForLong(Function<T, Long> getter) {
         LongPropertyValidator<T> validator = new LongPropertyValidator<>(getter);
         this.rules.add(validator::validate);
         return validator;
     }
 
+    protected final LongPropertyValidator<T> ruleFor(ToLongObjectFunction<T> getter) {
+        LongPropertyValidator<T> validator = new LongPropertyValidator<>(getter);
+        this.rules.add(validator::validate);
+        return validator;
+    }
+
     protected final DoublePropertyValidator<T> ruleForDouble(Function<T, Double> getter) {
         DoublePropertyValidator<T> validator = new DoublePropertyValidator<>(getter);
         this.rules.add(validator::validate);
         return validator;
     }
 
+    protected final DoublePropertyValidator<T> ruleFor(ToDoubleObjectFunction<T> getter) {
+        DoublePropertyValidator<T> validator = new DoublePropertyValidator<>(getter);
+        this.rules.add(validator::validate);
+        return validator;
+    }
+
     protected final BoolPropertyValidator<T> ruleForBool(Function<T, Boolean> getter) {
         BoolPropertyValidator<T> validator = new BoolPropertyValidator<>(getter);
         this.rules.add(validator::validate);
         return validator;
     }
 
+    protected final BoolPropertyValidator<T> ruleFor(ToBoolObjectFunction<T> getter) {
+        BoolPropertyValidator<T> validator = new BoolPropertyValidator<>(getter);
+        this.rules.add(validator::validate);
+        return validator;
+    }
+
     protected final StringPropertyValidator<T> ruleForString(Function<T, String> getter) {
         StringPropertyValidator<T> validator = new StringPropertyValidator<>(getter);
         this.rules.add(validator::validate);
         return validator;
     }
 
+    protected final StringPropertyValidator<T> ruleFor(ToStringFunction<T> getter) {
+        StringPropertyValidator<T> validator = new StringPropertyValidator<>(getter);
+        this.rules.add(validator::validate);
+        return validator;
+    }
+
     protected final <E> CollectionPropertyValidator<T, E> ruleForCollection(Function<T, Collection<E>> getter) {
         CollectionPropertyValidator<T, E> validator = new CollectionPropertyValidator<>(getter);
         this.rules.add(validator::validate);

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/IValidateRequired.java

@@ -21,7 +21,6 @@ package xyz.zhouxy.plusone.validator;
  *
  * @author <a href="https://gitee.com/zhouxy108">ZhouXY</a>
  *
- * @see ValidTools
  * @see BaseValidator
  */
 public interface IValidateRequired {

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/MapValidator.java

@@ -60,7 +60,8 @@ public abstract class MapValidator<K, V> extends BaseValidator<Map<K, V>> {
     // ========== ruleFor ==========
 
     protected final ObjectPropertyValidator<Map<K, V>, V> ruleFor(K key) {
-        return ruleFor(m -> m.get(key));
+        final Function<Map<K, V>, V> func = m -> m.get(key);
+        return ruleFor(func);
     }
 
     protected final IntPropertyValidator<Map<K, V>> ruleForInt(K key) {
@@ -83,6 +84,12 @@ public abstract class MapValidator<K, V> extends BaseValidator<Map<K, V>> {
         return ruleForString(m -> (String) m.get(key));
     }
 
+    protected final <E extends Comparable<E>> ComparablePropertyValidator<Map<K, V>, E> ruleForComparable(K key) {
+        @SuppressWarnings("unchecked")
+        Function<Map<K, V>, E> getter = m -> (E) m.get(key);
+        return ruleForComparable(getter);
+    }
+
     protected final <E> CollectionPropertyValidator<Map<K, V>, E> ruleForCollection(K key) {
         @SuppressWarnings("unchecked")
         Function<Map<K, V>, Collection<E>> getter = m -> (Collection<E>) m.get(key);

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/StringPropertyValidator.java

@@ -269,8 +269,8 @@ public class StringPropertyValidator<T> extends BaseComparablePropertyValidator<
 
     public <E extends RuntimeException> StringPropertyValidator<T> length(int min, int max,
             Function<String, E> exceptionCreator) {
-        AssertTools.checkArgument(min >= 0, "The 'min' must be greater than or equal to 0.");
-        AssertTools.checkArgument(min <= max, "The 'min' must be less than or equal to the 'max'.");
+        AssertTools.checkArgument(min >= 0, "min must be non-negative.");
+        AssertTools.checkArgument(min <= max, "min must be less than or equal to max.");
         withRule(s -> length(s, min, max), exceptionCreator);
         return this;
     }

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/Validator.java

@@ -35,22 +35,16 @@ import java.util.function.Supplier;
  * </pre>
  *
  * <p>
- * 然后通过校验器的 {@link #validate} 方法，或
- * {@link ValidTools#validate(Object, Validator)} 对指定对象进行校验。
+ * 然后通过校验器的 {@link #validate} 方法对指定对象进行校验。
  * </p>
  *
  * <pre>
  * validator.validate(666);
  * </pre>
- *
- * <pre>
- * ValidTools.validate(255, validator);
- * </pre>
  * </p>
  *
  * @author <a href="https://gitee.com/zhouxy108">ZhouXY</a>
  * @see IValidateRequired
- * @see ValidTools
  * @see BaseValidator
  */
 public final class Validator<T> extends BaseValidator<T> {

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/function/ToBoolObjectFunction.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 xyz.zhouxy.plusone.validator.function;
+
+import java.io.Serializable;
+import java.util.function.Function;
+
+@FunctionalInterface
+public interface ToBoolObjectFunction<T> extends Function<T, Boolean>, Serializable {
+}

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/function/ToDoubleObjectFunction.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 xyz.zhouxy.plusone.validator.function;
+
+import java.io.Serializable;
+import java.util.function.Function;
+
+@FunctionalInterface
+public interface ToDoubleObjectFunction<T> extends Function<T, Double>, Serializable {
+}

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/function/ToIntegerFunction.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 xyz.zhouxy.plusone.validator.function;
+
+import java.io.Serializable;
+import java.util.function.Function;
+
+@FunctionalInterface
+public interface ToIntegerFunction<T> extends Function<T, Integer>, Serializable {
+}

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/function/ToLongObjectFunction.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 xyz.zhouxy.plusone.validator.function;
+
+import java.io.Serializable;
+import java.util.function.Function;
+
+@FunctionalInterface
+public interface ToLongObjectFunction<T> extends Function<T, Long>, Serializable {
+}

plusone-validator/src/main/java/xyz/zhouxy/plusone/validator/function/ToStringFunction.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 xyz.zhouxy.plusone.validator.function;
+
+import java.io.Serializable;
+import java.util.function.Function;
+
+@FunctionalInterface
+public interface ToStringFunction<T> extends Function<T, String>, Serializable {
+}

plusone-validator/src/test/java/xyz/zhouxy/plusone/example/validator/BaseValidatorTest.java

@@ -1,3 +1,19 @@
+/*
+ * Copyright 2023-2025 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 xyz.zhouxy.plusone.example.validator;
 
 import static org.junit.jupiter.api.Assertions.*;

plusone-validator/src/test/java/xyz/zhouxy/plusone/example/validator/ObjectPropertyValidatorTests.java

@@ -18,6 +18,7 @@ package xyz.zhouxy.plusone.example.validator;
 
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import java.time.DateTimeException;
@@ -44,12 +45,12 @@ public class ObjectPropertyValidatorTests {
     // ================================
 
     @Test
-    void withRule() {
+    void withRule_validInput() {
         BaseValidator<ExampleCommand> validator = new BaseValidator<ExampleCommand>() {
             {
                 ruleFor(ExampleCommand::getBoolProperty)
                         .notNull("The boolProperty cannot be null.")
-                        .withRule(Boolean.TRUE::equals, "The boolProperty should be true.");
+                        .withRule(Boolean.TRUE::equals);
 
                 ruleFor(ExampleCommand::getIntProperty)
                         .withRule(intProperty -> intProperty > 0, "The intProperty should be greater than 0.");
@@ -99,6 +100,50 @@ public class ObjectPropertyValidatorTests {
         assertDoesNotThrow(() -> validator.validate(command));
     }
 
+    @Test
+    void withRule_invalidInputs() {
+        ExampleCommand command = new ExampleCommand();
+        BaseValidator<ExampleCommand> ruleWithDefaultMessage = new BaseValidator<ExampleCommand>() {
+            {
+                ruleFor(ExampleCommand::getObjectProperty)
+                        .withRule(x -> false);
+            }
+        };
+        IllegalArgumentException eWithDefaultMessage = assertThrows(
+                IllegalArgumentException.class, () -> ruleWithDefaultMessage.validate(command));
+        assertNull(eWithDefaultMessage.getMessage());
+
+        BaseValidator<ExampleCommand> ruleWithMessage = new BaseValidator<ExampleCommand>() {
+            {
+                ruleFor(ExampleCommand::getObjectProperty)
+                        .withRule(x -> false, "invalid input.");
+            }
+        };
+        IllegalArgumentException eWithMessage = assertThrows(
+                IllegalArgumentException.class, () -> ruleWithMessage.validate(command));
+        assertEquals("invalid input.", eWithMessage.getMessage());
+
+        BaseValidator<ExampleCommand> ruleWithExceptionSupplier = new BaseValidator<ExampleCommand>() {
+            {
+                ruleFor(ExampleCommand::getObjectProperty)
+                        .withRule(x -> false, () -> ExampleException.withMessage("invalid input."));
+            }
+        };
+        ExampleException specifiedException = assertThrows(
+                ExampleException.class, () -> ruleWithExceptionSupplier.validate(command));
+        assertEquals("invalid input.", specifiedException.getMessage());
+
+        BaseValidator<ExampleCommand> ruleWithExceptionFunction = new BaseValidator<ExampleCommand>() {
+            {
+                ruleFor(ExampleCommand::getObjectProperty)
+                        .withRule(x -> false, x -> ExampleException.withMessage("invalid input: [%s].", x));
+            }
+        };
+        ExampleException specifiedException2 = assertThrows(
+                ExampleException.class, () -> ruleWithExceptionFunction.validate(command));
+        assertEquals("invalid input: [null].", specifiedException2.getMessage());
+    }
+
     // ================================
     // #endregion - withRule
     // ================================
@@ -273,19 +318,19 @@ public class ObjectPropertyValidatorTests {
     // ================================
 
     // ================================
-    // #region - equalsThat
+    // #region - equalTo
     // ================================
 
     @Test
-    void equalsThat_validInput() {
+    void equalTo_validInput() {
         BaseValidator<ExampleCommand> validator = new BaseValidator<ExampleCommand>() {
             {
                 ruleForString(ExampleCommand::getStringProperty)
-                        .equalsThat("Foo")
-                        .equalsThat("Foo", "The stringProperty should be equal to 'Foo'.")
-                        .equalsThat("Foo", () ->
+                        .equalTo("Foo")
+                        .equalTo("Foo", "The stringProperty should be equal to 'Foo'.")
+                        .equalTo("Foo", () ->
                                 ExampleException.withMessage("The stringProperty should be equal to 'Foo'."))
-                        .equalsThat("Foo", str ->
+                        .equalTo("Foo", str ->
                                 ExampleException.withMessage("The stringProperty should be equal to 'Foo', but is was '%s'.", str));
             }
         };
@@ -296,13 +341,13 @@ public class ObjectPropertyValidatorTests {
     }
 
     @Test
-    void equalsThat_invalidInput() {
+    void equalTo_invalidInput() {
         ExampleCommand command = new ExampleCommand();
         command.setStringProperty("Bar");
 
         BaseValidator<ExampleCommand> defaultRule = new BaseValidator<ExampleCommand>() {
             {
-                ruleForString(ExampleCommand::getStringProperty).equalsThat("Foo");
+                ruleForString(ExampleCommand::getStringProperty).equalTo("Foo");
             }
         };
         IllegalArgumentException eWithDefaultMessage = assertThrows(
@@ -311,7 +356,7 @@ public class ObjectPropertyValidatorTests {
 
         BaseValidator<ExampleCommand> ruleWithMessage = new BaseValidator<ExampleCommand>() {
             {
-                ruleForString(ExampleCommand::getStringProperty).equalsThat("Foo",
+                ruleForString(ExampleCommand::getStringProperty).equalTo("Foo",
                         "The stringProperty should be equal to 'Foo'.");
             }
         };
@@ -321,7 +366,7 @@ public class ObjectPropertyValidatorTests {
 
         BaseValidator<ExampleCommand> ruleWithExceptionSupplier = new BaseValidator<ExampleCommand>() {
             {
-                ruleForString(ExampleCommand::getStringProperty).equalsThat("Foo",
+                ruleForString(ExampleCommand::getStringProperty).equalTo("Foo",
                         () -> ExampleException.withMessage("The stringProperty should be equal to 'Foo'."));
             }
         };
@@ -331,7 +376,7 @@ public class ObjectPropertyValidatorTests {
 
         BaseValidator<ExampleCommand> ruleWithExceptionFunction = new BaseValidator<ExampleCommand>() {
             {
-                ruleForString(ExampleCommand::getStringProperty).equalsThat("Foo",
+                ruleForString(ExampleCommand::getStringProperty).equalTo("Foo",
                         str -> ExampleException.withMessage("The stringProperty should be equal to 'Foo', but is was '%s'.", str));
             }
         };
@@ -341,12 +386,12 @@ public class ObjectPropertyValidatorTests {
     }
 
     @Test
-    void equalsThat_nullInput() {
+    void equalTo_nullInput() {
         ExampleCommand command = new ExampleCommand();
 
         BaseValidator<ExampleCommand> defaultRule = new BaseValidator<ExampleCommand>() {
             {
-                ruleForString(ExampleCommand::getStringProperty).equalsThat("Foo");
+                ruleForString(ExampleCommand::getStringProperty).equalTo("Foo");
             }
         };
         IllegalArgumentException eWithDefaultMessage = assertThrows(
@@ -355,7 +400,7 @@ public class ObjectPropertyValidatorTests {
 
         BaseValidator<ExampleCommand> ruleWithMessage = new BaseValidator<ExampleCommand>() {
             {
-                ruleForString(ExampleCommand::getStringProperty).equalsThat("Foo",
+                ruleForString(ExampleCommand::getStringProperty).equalTo("Foo",
                         "The stringProperty should be equal to 'Foo'.");
             }
         };
@@ -365,7 +410,7 @@ public class ObjectPropertyValidatorTests {
 
         BaseValidator<ExampleCommand> ruleWithExceptionSupplier = new BaseValidator<ExampleCommand>() {
             {
-                ruleForString(ExampleCommand::getStringProperty).equalsThat("Foo",
+                ruleForString(ExampleCommand::getStringProperty).equalTo("Foo",
                         () -> ExampleException.withMessage("The stringProperty should be equal to 'Foo'."));
             }
         };
@@ -375,7 +420,7 @@ public class ObjectPropertyValidatorTests {
 
         BaseValidator<ExampleCommand> ruleWithExceptionFunction = new BaseValidator<ExampleCommand>() {
             {
-                ruleForString(ExampleCommand::getStringProperty).equalsThat("Foo",
+                ruleForString(ExampleCommand::getStringProperty).equalTo("Foo",
                         str -> ExampleException.withMessage("The stringProperty should be equal to 'Foo', but is was '%s'.", str));
             }
         };
@@ -385,7 +430,7 @@ public class ObjectPropertyValidatorTests {
     }
 
     // ================================
-    // #endregion - equalsThat
+    // #endregion - equalTo
     // ================================
 
     // ================================

plusone-validator/src/test/java/xyz/zhouxy/plusone/example/validator/ValidatorTests.java

@@ -1,3 +1,19 @@
+/*
+ * Copyright 2024-2025 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 xyz.zhouxy.plusone.example.validator;
 
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;

plusone-validator/src/test/java/xyz/zhouxy/plusone/map/validator/MapValidatorTests.java

@@ -1,3 +1,19 @@
+/*
+ * Copyright 2024-2025 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 xyz.zhouxy.plusone.map.validator;
 
 import static org.junit.jupiter.api.Assertions.*;
@@ -102,7 +118,7 @@ class ParamsValidator extends MapValidator<String, Object> {
                 .notNull(d -> ExampleException.withMessage("The doubleProperty cannot be null, but it was %s", d));
         ruleForString(STRING_PROPERTY)
                 .notNull();
-        ruleFor(DATE_TIME_PROPERTY)
+        ruleForComparable(DATE_TIME_PROPERTY)
                 .notNull("The dateTimeProperty cannot be null");
         ruleFor(OBJECT_PROPERTY)
                 .notNull(() -> ExampleException.withMessage("The objectProperty cannot be null"));