org.apache.ratis.util

Interface ReflectionUtils

public interface ReflectionUtils

Reflection related utility methods.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	ReflectionUtils.Classes
static class	ReflectionUtils.Constructors

Method Summary

Modifier and Type	Method and Description
static <BASE> Class<? extends BASE>	getClass(String subClassName, Class<BASE> base)
static Class<?>	getClassByName(String name) Load a class by name.
static Class<?>	getClassByName(String name, ClassLoader classLoader) Load a class by name through a specific classloader.
static Class<?>	getClassByNameOrNull(String name) Load a class by name, returning null rather than throwing an exception if it couldn't be loaded.
static Class<?>	getClassByNameOrNull(String name, ClassLoader classLoader) Load a class by name through a specific classloader, returning null rather than throwing an exception if it couldn't be loaded.
static ClassLoader	getClassLoader()
static <BASE> Class<? extends BASE>	getImplClass(Class<BASE> base)
static String	getImplClassName(Class<?> clazz)
static <T> T	instantiate(String className, Constructor<T> ctor, Object[] ctorArgs)
static <T extends Throwable> T	instantiateException(Class<T> clazz)
static <T extends Throwable> T	instantiateException(Class<T> clazz, String message)
static boolean	isInstance(Object obj, Class<?>... classes) Is the given object an instance of one of the given classes?
static <T> T	newInstance(Class<T> clazz) Create an object for the given class using its default constructor.
static <T> T	newInstance(Class<T> clazz, Class<?>[] argClasses, Object... args) Create an object for the given class using the specified constructor.

Method Detail

getClassLoader

static ClassLoader getClassLoader()

getClassByNameOrNull

static Class<?> getClassByNameOrNull(String name)

Load a class by name, returning null rather than throwing an exception if it couldn't be loaded. This is to avoid the overhead of creating an exception.

Parameters:

name - the class name

Returns:

the class object, or null if it could not be found.

getClassByNameOrNull

static Class<?> getClassByNameOrNull(String name,
                                     ClassLoader classLoader)

Load a class by name through a specific classloader, returning null rather than throwing an exception if it couldn't be loaded. This is to avoid the overhead of creating an exception.

Parameters:

name - the class name

classLoader - the classloader

Returns:

the class object, or null if it could not be found.

getClassByName

static Class<?> getClassByName(String name)
                        throws ClassNotFoundException

Load a class by name.

Parameters:

name - the class name.

Returns:

the class object.

Throws:

ClassNotFoundException - if the class is not found.

getClassByName

static Class<?> getClassByName(String name,
                               ClassLoader classLoader)
                        throws ClassNotFoundException

Load a class by name through a specific classloader.

Parameters:

name - the class name.

classLoader - the classloader.

Returns:

the class object.

Throws:

ClassNotFoundException - if the class is not found.

newInstance

static <T> T newInstance(Class<T> clazz)

Create an object for the given class using its default constructor.

newInstance

static <T> T newInstance(Class<T> clazz,
                         Class<?>[] argClasses,
                         Object... args)

Create an object for the given class using the specified constructor.

Type Parameters:

T - class type of clazz

Parameters:

clazz - class of which an object is created

argClasses - argument classes of the constructor

args - actual arguments to be passed to the constructor

Returns:

a new object

instantiate

static <T> T instantiate(String className,
                         Constructor<T> ctor,
                         Object[] ctorArgs)

isInstance

static boolean isInstance(Object obj,
                          Class<?>... classes)

Is the given object an instance of one of the given classes?

getImplClassName

static String getImplClassName(Class<?> clazz)

getImplClass

static <BASE> Class<? extends BASE> getImplClass(Class<BASE> base)

getClass

static <BASE> Class<? extends BASE> getClass(String subClassName,
                                             Class<BASE> base)

instantiateException

static <T extends Throwable> T instantiateException(Class<T> clazz)
                                             throws Exception

Throws:

Exception

instantiateException

static <T extends Throwable> T instantiateException(Class<T> clazz,
                                                    String message)
                                             throws Exception

Throws:

Exception