io.neba.core.util

Class ReflectionUtil

java.lang.Object

io.neba.core.util.ReflectionUtil

public final class ReflectionUtil
extends Object

Author:

Olaf Otto

Method Summary

Modifier and Type	Method and Description
static Field	findField(Class<?> type, String name)
static Type	getBoundaryOfParametrizedType(Type type, Type assigningType) Resolves the Type of the lower, or, if no lower bound is present, the upper bound of a single type argument of a ParameterizedType.
static Class<?>[]	getInstantiableCollectionTypes()
static <K,T extends Collection<K>> Collection<K>	instantiateCollectionType(Class<T> collectionType) Creates an instance with a default capacity.
static <K,T extends Collection<K>> Collection<K>	instantiateCollectionType(Class<T> collectionType, int length) Provides an implementation instance for the desired collection type.
static boolean	isInstantiableCollectionType(Class<?> type)
static Field	makeAccessible(Field field) Makes the accessible only if it is not.
static Method	makeAccessible(Method method) Makes the accessible only if it is not.
static List<Method>	methodsOf(Class<?> type) All methods of the given type, its super types and interfaces, starting with the methods of the given type.

Methods inherited from class java.lang.Object

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

Method Detail

getBoundaryOfParametrizedType

public static Type getBoundaryOfParametrizedType(Type type,
                                                 Type assigningType)

Resolves the Type of the lower, or, if no lower bound is present, the upper bound of a single type argument of a ParameterizedType.

   private List<MyModel> myModel -> MyModel.
   private List<? extends MyModel> myModel -> MyModel.
   private List<? super MyModel> myModel -> MyModel.
   private List<T> myModel | T extends MyModel -> MyModel.
   private Optional<MyModel> myModel -> MyModel.
 

Parameters:

type - must not be null.

Returns:

never null.

instantiateCollectionType

public static <K,T extends Collection<K>> Collection<K> instantiateCollectionType(Class<T> collectionType,
                                                                                  int length)

Provides an implementation instance for the desired collection type. Example: If the collection type is List, a suitable list implementation is instantiated.

Parameters:

collectionType - must not be null.

Returns:

never null. Throws an IllegalStateException if the collection type is not supported.

isInstantiableCollectionType

public static boolean isInstantiableCollectionType(Class<?> type)

Parameters:

type - must not be null.

Returns:

whether the given collection type can be instantiated using instantiateCollectionType(Class).

getInstantiableCollectionTypes

public static Class<?>[] getInstantiableCollectionTypes()

Returns:

an array of the types a collection type must be assignable from in order to be instantiable.

instantiateCollectionType

public static <K,T extends Collection<K>> Collection<K> instantiateCollectionType(Class<T> collectionType)

Creates an instance with a default capacity.

See Also:

instantiateCollectionType(Class, int)

methodsOf

public static List<Method> methodsOf(Class<?> type)

All methods of the given type, its super types and interfaces, starting with the methods of the given type.

Parameters:

type - must not be null.

Returns:

never null but rather an empty list.

findField

public static Field findField(Class<?> type,
                              String name)

Parameters:

type - must not be null.

name - must not be null.

Returns:

the declared field with the given name, or null

makeAccessible

public static Field makeAccessible(Field field)

Makes the accessible only if it is not.

Parameters:

field - must not be null.

Returns:

the given field.

makeAccessible

public static Method makeAccessible(Method method)

Makes the accessible only if it is not.

Parameters:

method - must not be null.

Returns:

the given method.