/*
* Hibernate Validator, declare and validate application constraints
*
* License: Apache License, Version 2.0
* See the license.txt file in the root directory or <http://www.apache.org/licenses/LICENSE-2.0>.
*/
package org.hibernate.validator.internal.metadata.location;
import java.lang.reflect.Executable;
import java.lang.reflect.Field;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import org.hibernate.validator.internal.engine.path.PathImpl;
import org.hibernate.validator.internal.util.ExecutableParameterNameProvider;
/**
* Represents the location (e.g. a bean, field or method parameter) of a constraint and provides logic related to it,
* e.g. for appending the location to a given property path.
* <p>
* Note that while the validation engine works on the aggregated meta-model (which e.g. provides a unified view for
* properties, be them represented via fields or getter methods) most of the time, in some situations the physical
* element which hosts a constraint is relevant. This includes
* <ul>
* <li>retrieval of property values to be validated (either field or getter access)</li>
* <li>constraint validator resolution; a field and the corresponding getter method may have different types, causing
* potentially different validators to kick in for the constraints declared on either element</li>
* <li>determination of a constraint's scope (locally defined or up in the hierarchy)</li>
* </ul>
*
* @author Hardy Ferentschik
* @author Gunnar Morling
*/
public interface ConstraintLocation {
static ConstraintLocation forClass(Class<?> declaringClass) {
return new BeanConstraintLocation( declaringClass );
}
static ConstraintLocation forField(Field field) {
return new FieldConstraintLocation( field );
}
static ConstraintLocation forGetter(Method getter) {
return new GetterConstraintLocation( getter );
}
static ConstraintLocation forTypeArgument(ConstraintLocation delegate, TypeVariable<?> typeParameter, Type typeOfAnnotatedElement) {
return new TypeArgumentConstraintLocation( delegate, typeParameter, typeOfAnnotatedElement );
}
static ConstraintLocation forReturnValue(Executable executable) {
return new ReturnValueConstraintLocation( executable );
}
static ConstraintLocation forCrossParameter(Executable executable) {
return new CrossParameterConstraintLocation( executable );
}
static ConstraintLocation forParameter(Executable executable, int index) {
return new ParameterConstraintLocation( executable, index );
}
/**
* Returns the class hosting this location.
*/
Class<?> getDeclaringClass();
/**
* Returns the member represented by this location.
*
* @return the member represented by this location. Will be {@code null} when this location represents a type.
*/
Member getMember();
/**
* Returns the type to be used when resolving constraint validators for constraints at this location. Note that this
* is not always the same type as the type of the element described by this location; E.g. the wrapper type will is
* used for constraint validator resolution, if a constraint is declared in an element with a primitive type.
*
* @return The type to be used when resolving constraint validators for constraints at this location
*/
Type getTypeForValidatorResolution();
/**
* Appends a node representing this location to the given property path.
*/
void appendTo(ExecutableParameterNameProvider parameterNameProvider, PathImpl path);
/**
* Obtains the value of this location from the parent. The type of the passed parent depends on the location type,
* e.g. a bean would be passed for a {@link FieldConstraintLocation} or {@link GetterConstraintLocation} but an
* object array for a {@link ParameterConstraintLocation}.
*/
Object getValue(Object parent);
}