revxrsal.commands.util

Class Classes

java.lang.Object

revxrsal.commands.util.Classes

public final class Classes
extends java.lang.Object

A utility class for dealing with wrapping and unwrapping of primitive types

Method Summary

Modifier and Type	Method and Description
static @Nullable java.lang.reflect.Type	arrayComponentType(java.lang.reflect.Type type) Returns the array type of the given type.
static void	checkRetention(@NotNull java.lang.Class<? extends java.lang.annotation.Annotation> type) Checks whether the given annotation type has Retention of RetentionPolicy.RUNTIME.
static java.lang.reflect.Type	getFirstGeneric(@NotNull java.lang.Class<?> cl, @NotNull java.lang.reflect.Type fallback) Deprecated. Classes do not have generics. You might have passed the wrong parameters.
static java.lang.reflect.Type	getFirstGeneric(@NotNull java.lang.reflect.Type genericType, @NotNull java.lang.reflect.Type fallback) Returns the first generic type of the given (possibly parameterized) type genericType.
static java.lang.Class<?>	getRawType(java.lang.reflect.Type type) Returns the Class object representing the class or interface that declared this type.
static java.lang.Class<?>	getType(@NotNull java.lang.Object o) Returns the type of the given object
static boolean	isClassPresent(@NotNull java.lang.String name) Tests whether the given class is available or not
static boolean	isWrapperType(java.lang.Class<?> type) Returns true if the specified type is one of the nine primitive-wrapper types, such as Integer.
static <T> java.lang.Class<T>	unwrap(java.lang.Class<T> type) Returns the corresponding primitive type of type if it is a wrapper type; otherwise returns the type itself.
static <T> java.lang.Class<T>	wrap(java.lang.Class<T> type) Returns the corresponding wrapper type of type if it is a primitive type; otherwise returns the type itself.

Methods inherited from class java.lang.Object

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

Method Detail

getType

public static java.lang.Class<?> getType(@NotNull
                                         @NotNull java.lang.Object o)

Returns the type of the given object

Parameters:

o - Object to get for

Returns:

The object type

wrap

public static <T> java.lang.Class<T> wrap(java.lang.Class<T> type)

Returns the corresponding wrapper type of type if it is a primitive type; otherwise returns the type itself.

     wrap(int.class) == Integer.class
     wrap(Integer.class) == Integer.class
     wrap(String.class) == String.class
 

arrayComponentType

@Nullable
public static @Nullable java.lang.reflect.Type arrayComponentType(java.lang.reflect.Type type)

Returns the array type of the given type. This will respect generics of the array type.

Parameters:

type - The type to parse from

Returns:

The array type, or null if it does not represent an array.

unwrap

public static <T> java.lang.Class<T> unwrap(java.lang.Class<T> type)

Returns the corresponding primitive type of type if it is a wrapper type; otherwise returns the type itself.

     unwrap(Integer.class) == int.class
     unwrap(int.class) == int.class
     unwrap(String.class) == String.class
 

isWrapperType

public static boolean isWrapperType(java.lang.Class<?> type)

Returns true if the specified type is one of the nine primitive-wrapper types, such as Integer.

Parameters:

type - Type to check

See Also:

Class.isPrimitive()

getRawType

public static java.lang.Class<?> getRawType(java.lang.reflect.Type type)

Returns the Class object representing the class or interface that declared this type.

Returns:

the Class object representing the class or interface that declared this type

getFirstGeneric

@Deprecated
 @Contract(value="_,_ -> param2")
public static java.lang.reflect.Type getFirstGeneric(@NotNull
                                                                                                   @NotNull java.lang.Class<?> cl,
                                                                                                   @NotNull
                                                                                                   @NotNull java.lang.reflect.Type fallback)

Deprecated. Classes do not have generics. You might have passed the wrong parameters.

Returns the first generic type of the given class. Because classes do not have generics, this function emits a warning to inform them that they probably passed the wrong type argument, and meant to invoke getFirstGeneric(Type, Type) instead.

Parameters:

cl - The class. This parameter is ignored

fallback - The fallback to return

Returns:

The fallback type

See Also:

getFirstGeneric(Type, Type)

getFirstGeneric

public static java.lang.reflect.Type getFirstGeneric(@NotNull
                                                     @NotNull java.lang.reflect.Type genericType,
                                                     @NotNull
                                                     @NotNull java.lang.reflect.Type fallback)

Returns the first generic type of the given (possibly parameterized) type genericType. If the type is not parameterized, this will return fallback.

Parameters:

genericType - The generic type

fallback - The fallback to return

Returns:

The generic type

isClassPresent

public static boolean isClassPresent(@NotNull
                                     @NotNull java.lang.String name)

Tests whether the given class is available or not

Parameters:

name - Class name to test

Returns:

If the class is present or not

checkRetention

public static void checkRetention(@NotNull
                                  @NotNull java.lang.Class<? extends java.lang.annotation.Annotation> type)

Checks whether the given annotation type has Retention of RetentionPolicy.RUNTIME. This helps catch user errors where a certain annotation is being checked for, that may have been omitted because it does not have a runtime retention policy.

Parameters:

type - Annotation to check