You can declare additional validations and metadata for your parameters.

Generic validations and metadata:

* `alias`
* `title`
* `description`
* `deprecated`

Validations specific for strings:

* `min_length`
* `max_length`
* `pattern`

Custom validations using `AfterValidator`.

In these examples you saw how to declare validations for `str` values.

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.validation;

import java.lang.annotation.Annotation;

import org.codelibs.fess.unit.UnitFessTestCase;

import jakarta.validation.ConstraintValidatorContext;
import jakarta.validation.Payload;

public class CustomSizeValidatorTest extends UnitFessTestCase {

    private CustomSizeValidator validator;

        } catch (SMBProtocolDecodingException e) {
            // If exception thrown, validation is working
            assertTrue(e.getMessage().contains("Invalid negotiate context data length") || e.getMessage().contains("Buffer too small")
                    || e.getMessage().contains("negotiate context"), "Validation detected issue: " + e.getMessage());
        }

 */
package org.codelibs.fess.validation;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Set;

import org.codelibs.fess.unit.UnitFessTestCase;

import jakarta.validation.ConstraintViolation;
import jakarta.validation.Validation;
import jakarta.validation.Validator;
import jakarta.validation.ValidatorFactory;

Another big feature needed by APIs is data validation, making sure that the data is valid, given certain parameters. For example, that some field is an `int`, and not some random string. This is especially useful for incoming data.

Without a data validation system, you would have to do all the checks by hand, in code.

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.validation;

import org.codelibs.fess.unit.UnitFessTestCase;

import jakarta.validation.ConstraintValidatorContext;

public class CronExpressionValidatorTest extends UnitFessTestCase {

    public CronExpressionValidator validator;

    @Override

    @Test
    @DisplayName("Test invalid buffer size validation")
    void testInvalidBufferSize() {
        assertThrows(IllegalArgumentException.class, () -> InputValidator.validateBufferSize(-1, 1000, "test"));
        assertThrows(IllegalArgumentException.class, () -> InputValidator.validateBufferSize(1001, 1000, "test"));
    }

    @Test
    @DisplayName("Test SMB2 buffer size validation")
    void testSmb2BufferSize() {

    * If you didn't use FastAPI and used Starlette directly (or another tool, like Sanic, Flask, Responder, etc) you would have to implement all the data validation and serialization yourself. So, your final application would still have...

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

import org.codelibs.core.lang.StringUtil;
import org.codelibs.fess.unit.UnitFessTestCase;

import jakarta.validation.Constraint;
import jakarta.validation.Payload;

public class CustomSizeTest extends UnitFessTestCase {

    // Test field with CustomSize annotation for testing
    @CustomSize(minKey = "test.min", maxKey = "test.max")

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.validation;

import org.codelibs.fess.unit.UnitFessTestCase;
import org.lastaflute.core.message.UserMessages;
import org.lastaflute.core.message.supplier.UserMessagesCreator;
import org.lastaflute.web.servlet.request.RequestManager;
import org.lastaflute.web.validation.ActionValidator;

public class FessActionValidatorTest extends UnitFessTestCase {