org.hibernate.validator.util
Class ReflectionHelper

java.lang.Object
  org.hibernate.validator.util.ReflectionHelper

public final class ReflectionHelper
extends java.lang.Object

Some reflection utility methods. Where necessary calls will be performed as PrivilegedAction which is necessary for situations where a security manager is in place.

Author:

Hardy Ferentschik

Method Summary

static java.lang.Class<?>	boxedType(java.lang.reflect.Type primitiveType) Returns the autoboxed type of a primitive type.
static java.util.List<java.lang.Class<?>>	computeClassHierarchy(java.lang.Class<?> clazz) Get all superclasses and interfaces recursively.
static boolean	containsField(java.lang.Class<?> clazz, java.lang.String fieldName) Checks whether the specified class contains a field with the given name.
static boolean	containsMethod(java.lang.Class<?> clazz, java.lang.String methodName) Checks whether the specified class contains a method with the given name.
static boolean	containsMethodWithPropertyName(java.lang.Class<?> clazz, java.lang.String property) Checks whether the specified class contains a method for the specified property.
static <T> T	getAnnotationParameter(java.lang.annotation.Annotation annotation, java.lang.String parameterName, java.lang.Class<T> type)
static java.lang.ClassLoader	getClassLoaderFromClass(java.lang.Class<?> clazz)
static java.lang.ClassLoader	getClassLoaderFromContext()
static <T> java.lang.reflect.Constructor<T>	getConstructor(java.lang.Class<T> clazz, java.lang.Class<?>... params)
static java.lang.reflect.Field	getField(java.lang.Class<?> clazz, java.lang.String fieldName) Returns the field with the specified name or null if it does not exist.
static java.lang.reflect.Field[]	getFields(java.lang.Class<?> clazz) Returns the fields of the specified class.
static java.lang.reflect.Type	getIndexedType(java.lang.reflect.Type type) Determines the type of elements of an Iterable, array or the value of a Map.
static java.lang.Object	getIndexedValue(java.lang.Object value, java.lang.Integer index) Tries to retrieve the indexed value from the specified object.
static java.lang.Object	getMappedValue(java.lang.Object value, java.lang.Object key) Tries to retrieve the mapped value from the specified object.
static java.lang.reflect.Member	getMember(java.lang.Class<?> clazz, java.lang.String property, java.lang.annotation.ElementType elementType) Returns the member with the given name and type.
static java.lang.reflect.Method	getMethod(java.lang.Class<?> clazz, java.lang.String methodName) Returns the method with the specified name or null if it does not exist.
static java.lang.reflect.Method	getMethodFromPropertyName(java.lang.Class<?> clazz, java.lang.String methodName) Returns the method with the specified property name or null if it does not exist.
static java.lang.reflect.Method[]	getMethods(java.lang.Class<?> clazz) Returns the methods of the specified class.
static java.lang.String	getPropertyName(java.lang.reflect.Member member) Process bean properties getter by applying the JavaBean naming conventions.
static java.lang.Class<?>	getType(java.lang.reflect.Member member) Returns the type of the field of return type of a method.
static java.lang.Object	getValue(java.lang.reflect.Member member, java.lang.Object object)
static boolean	isIterable(java.lang.reflect.Type type)
static boolean	isList(java.lang.reflect.Type type)
static boolean	isMap(java.lang.reflect.Type type)
static java.lang.Class<?>	loadClass(java.lang.String className, java.lang.Class<?> caller)
static <T> T	newConstructorInstance(java.lang.reflect.Constructor<T> constructor, java.lang.Object... initArgs)
static <T> T	newInstance(java.lang.Class<T> clazz, java.lang.String message)
static boolean	propertyExists(java.lang.Class<?> clazz, java.lang.String property, java.lang.annotation.ElementType elementType) Checks whether the property with the specified name and type exists on the given class.
static void	setAccessibility(java.lang.reflect.Member member)
static java.lang.reflect.Type	typeOf(java.lang.reflect.Member member)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getClassLoaderFromContext

public static java.lang.ClassLoader getClassLoaderFromContext()

getClassLoaderFromClass

public static java.lang.ClassLoader getClassLoaderFromClass(java.lang.Class<?> clazz)

loadClass

public static java.lang.Class<?> loadClass(java.lang.String className,
                                           java.lang.Class<?> caller)

getConstructor

public static <T> java.lang.reflect.Constructor<T> getConstructor(java.lang.Class<T> clazz,
                                                                  java.lang.Class<?>... params)

newInstance

public static <T> T newInstance(java.lang.Class<T> clazz,
                                java.lang.String message)

newConstructorInstance

public static <T> T newConstructorInstance(java.lang.reflect.Constructor<T> constructor,
                                           java.lang.Object... initArgs)

getAnnotationParameter

public static <T> T getAnnotationParameter(java.lang.annotation.Annotation annotation,
                                           java.lang.String parameterName,
                                           java.lang.Class<T> type)

getPropertyName

public static java.lang.String getPropertyName(java.lang.reflect.Member member)

Process bean properties getter by applying the JavaBean naming conventions.

Parameters:

member - the member for which to get the property name.

Returns:

The bean method name with the "is" or "get" prefix stripped off, null the method name id not according to the JavaBeans standard.

propertyExists

public static boolean propertyExists(java.lang.Class<?> clazz,
                                     java.lang.String property,
                                     java.lang.annotation.ElementType elementType)

Checks whether the property with the specified name and type exists on the given class.

Parameters:

clazz - The class to check for the property. Cannot be null.

property - The property name without 'is', 'get' or 'has'. Cannot be null or empty.

elementType - The element type. Either ElementType.FIELD or ElementType METHOD.

Returns:

true is the property and can be access via the specified type, false otherwise.

getMember

public static java.lang.reflect.Member getMember(java.lang.Class<?> clazz,
                                                 java.lang.String property,
                                                 java.lang.annotation.ElementType elementType)

Returns the member with the given name and type.

Parameters:

clazz - The class from which to retrieve the member. Cannot be null.

property - The property name without 'is', 'get' or 'has'. Cannot be null or empty.

elementType - The element type. Either ElementType.FIELD or ElementType METHOD.

Returns:

the member which matching the name and type or null if no such member exists.

getType

public static java.lang.Class<?> getType(java.lang.reflect.Member member)

Returns the type of the field of return type of a method.

Parameters:

member - the member for which to get the type.

Returns:

Returns the type of the field of return type of a method.

typeOf

public static java.lang.reflect.Type typeOf(java.lang.reflect.Member member)

Parameters:

member - The Member instance for which to retrieve the type.

Returns:

Returns the Type of the given Field or Method.

Throws:

java.lang.IllegalArgumentException - in case member is not a Field or Method.

getValue

public static java.lang.Object getValue(java.lang.reflect.Member member,
                                        java.lang.Object object)

setAccessibility

public static void setAccessibility(java.lang.reflect.Member member)

getIndexedType

public static java.lang.reflect.Type getIndexedType(java.lang.reflect.Type type)

Determines the type of elements of an Iterable, array or the value of a Map.

Parameters:

type - the type to inspect

Returns:

Returns the type of elements of an Iterable, array or the value of a Map. null is returned in case the type is not indexable (in the context of JSR 303).

isIterable

public static boolean isIterable(java.lang.reflect.Type type)

Parameters:

type - the type to check.

Returns:

Returns true if type is a iterable type, false otherwise.

isMap

public static boolean isMap(java.lang.reflect.Type type)

Parameters:

type - the type to check.

Returns:

Returns true if type is implementing Map, false otherwise.

isList

public static boolean isList(java.lang.reflect.Type type)

Parameters:

type - the type to check.

Returns:

Returns true if type is implementing List, false otherwise.

getIndexedValue

public static java.lang.Object getIndexedValue(java.lang.Object value,
                                               java.lang.Integer index)

Tries to retrieve the indexed value from the specified object.

Parameters:

value - The object from which to retrieve the indexed value. The object has to be non null and either a collection or array.

index - The index. The index does not have to be numerical. value could also be a map in which case the index could also be a string key.

Returns:

The indexed value or null if value is null or not a collection or array. null is also returned in case the index does not exist.

getMappedValue

public static java.lang.Object getMappedValue(java.lang.Object value,
                                              java.lang.Object key)

Tries to retrieve the mapped value from the specified object.

Parameters:

value - The object from which to retrieve the mapped value. The object has to be non null and must implement the @{code Map} interface.

key - The map key. index.

Returns:

The mapped value or null if value is null or not implementing @{code Map}.

getField

public static java.lang.reflect.Field getField(java.lang.Class<?> clazz,
                                               java.lang.String fieldName)

Returns the field with the specified name or null if it does not exist.

Parameters:

clazz - The class to check.

fieldName - The field name.

Returns:

Returns the field with the specified name or null if it does not exist.

containsField

public static boolean containsField(java.lang.Class<?> clazz,
                                    java.lang.String fieldName)

Checks whether the specified class contains a field with the given name.

Parameters:

clazz - The class to check.

fieldName - The field name.

Returns:

Returns true if the field exists, false otherwise.

getFields

public static java.lang.reflect.Field[] getFields(java.lang.Class<?> clazz)

Returns the fields of the specified class.

Parameters:

clazz - The class for which to retrieve the fields.

Returns:

Returns the fields for this class.

getMethodFromPropertyName

public static java.lang.reflect.Method getMethodFromPropertyName(java.lang.Class<?> clazz,
                                                                 java.lang.String methodName)

Returns the method with the specified property name or null if it does not exist. This method will prepend 'is' and 'get' to the property name and capitalize the first letter.

Parameters:

clazz - The class to check.

methodName - The property name.

Returns:

Returns the method with the specified property or null if it does not exist.

containsMethodWithPropertyName

public static boolean containsMethodWithPropertyName(java.lang.Class<?> clazz,
                                                     java.lang.String property)

Checks whether the specified class contains a method for the specified property.

Parameters:

clazz - The class to check.

property - The property name.

Returns:

Returns true if the method exists, false otherwise.

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Class<?> clazz,
                                                 java.lang.String methodName)

Returns the method with the specified name or null if it does not exist.

Parameters:

clazz - The class to check.

methodName - The property name.

Returns:

Returns the method with the specified property or nullif it does not exist.

getMethods

public static java.lang.reflect.Method[] getMethods(java.lang.Class<?> clazz)

Returns the methods of the specified class.

Parameters:

clazz - The class for which to retrieve the methods.

Returns:

Returns the methods for this class.

containsMethod

public static boolean containsMethod(java.lang.Class<?> clazz,
                                     java.lang.String methodName)

Checks whether the specified class contains a method with the given name.

Parameters:

clazz - The class to check.

methodName - The method name.

Returns:

Returns true if the method exists, false otherwise.

boxedType

public static java.lang.Class<?> boxedType(java.lang.reflect.Type primitiveType)

Returns the autoboxed type of a primitive type.

Parameters:

primitiveType - the primitive type

Returns:

the autoboxed type of a primitive type.

Throws:

java.lang.IllegalArgumentException - in case the parameter primitiveType does not represent a primitive type.

computeClassHierarchy

public static java.util.List<java.lang.Class<?>> computeClassHierarchy(java.lang.Class<?> clazz)

Get all superclasses and interfaces recursively.

Parameters:

clazz - The class to start the search with.

Returns:

List of all super classes and interfaces of clazz. The list contains the class itself! The empty list is returned if clazz is null.