com.github.zhengframework.validator.ValidationGroups Maven / Gradle / Ivy

package com.github.zhengframework.validator;

import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import com.github.zhengframework.validator.aop.ValidationContext;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

/**
 * Defines validation groups used in validation of annotated method or any method called within it
 * (context defines). Annotation may be set on class to affect all methods or on method directly. If
 * defied on both class and method then groups from both annotations will be used.
 * 
 * Works much like transaction (e.g. @Transactional) - defines scope where groups are defined.
 * Definition is thread bound.
 * 

 * Inline contexts are also supported: e.g. annotated method defines groups scope; under this method
 * other annotated method is called - it will create new validation context with groups from both
 * annotations. This should allow writing generic logic and control validation inside it by groups
 * annotation in upper level services.
 * 

 * Annotation may be also declared on other annotation. This may be useful to group multiple group
 * annotations. But even in case of single group it could make groups more readable. Instead of:
 * {@code @ValidationGroups(CustomerGroup.class)} you can use simply {@code @CustomerGroup}. Where:
 * 

 * {@literal @}Target({TYPE, METHOD})
 * {@literal @}Retention(RetentionPolicy.RUNTIME)
 * {@literal @}ValidationGroups(CustomerGroup.class)
 *  public @interface CustomerGroup {}
 * 
 * NOTE: annotation class used as group name.
 *
 * @author Vyacheslav Rusakov
 * @see ValidationContext
 * @since 07.03.2016
 */
@Target({TYPE, METHOD, ANNOTATION_TYPE})
@Retention(RUNTIME)
@Inherited
public @interface ValidationGroups {

    /**
     * @return validation groups to be used.
     */
    Class[] value();
}