Class ClassUtils

java.lang.Object

org.apache.shiro.lang.util.ClassUtils

public final class ClassUtils
extends Object

Utility method library used to conveniently interact with Classes, such as acquiring them from the application ClassLoaders and instantiating Objects from them.

Since:

0.1

Method Summary

Modifier and Type	Method	Description
static <T> Class<T>	forName(String fqcn)	Attempts to load the specified class name from the current thread's context class loader, then the current ClassLoader (ClassUtils.class.getClassLoader()), then the system/application ClassLoader (ClassLoader.getSystemClassLoader(), in that order.
static List<Method>	getAnnotatedMethods(Class<?> type, Class<? extends Annotation> annotation)
static Constructor<?>	getConstructor(Class<?> clazz, Class<?>... argTypes)
static InputStream	getResourceAsStream(String name)	Returns the specified resource by checking the current thread's context class loader, then the current ClassLoader (ClassUtils.class.getClassLoader()), then the system/application ClassLoader (ClassLoader.getSystemClassLoader(), in that order, using getResourceAsStream(name).
static Object	instantiate(Constructor<?> ctor, Object... args)
static boolean	isAvailable(String fullyQualifiedClassName)
static Object	newInstance(Class<?> clazz)
static Object	newInstance(Class<?> clazz, Object... args)
static Object	newInstance(String fqcn)
static Object	newInstance(String fqcn, Object... args)
static void	removeAdditionalClassLoader()	Removes the additional ClassLoader set by setAdditionalClassLoader(ClassLoader).
static void	setAdditionalClassLoader(ClassLoader classLoader)	Sets additional ClassLoader for getResourceAsStream(String) and forName(String) to use It is used in addition to the thread context class loader and the system class loader.

Methods inherited from class java.lang.Object

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

Method Details

getResourceAsStream

public static InputStream getResourceAsStream(String name)

Returns the specified resource by checking the current thread's context class loader, then the current ClassLoader (ClassUtils.class.getClassLoader()), then the system/application ClassLoader (ClassLoader.getSystemClassLoader(), in that order, using getResourceAsStream(name).

Parameters:

name - the name of the resource to acquire from the classloader(s).

Returns:

the InputStream of the resource found, or null if the resource cannot be found from any of the three mentioned ClassLoaders.

Since:

0.9

forName

public static <T> Class<T> forName(String fqcn)
                            throws UnknownClassException

Attempts to load the specified class name from the current thread's context class loader, then the current ClassLoader (ClassUtils.class.getClassLoader()), then the system/application ClassLoader (ClassLoader.getSystemClassLoader(), in that order. If any of them cannot locate the specified class, an UnknownClassException is thrown (our RuntimeException equivalent of the JRE's ClassNotFoundException.

Parameters:

fqcn - the fully qualified class name to load

Returns:

the located class

Throws:

UnknownClassException - if the class cannot be found.

isAvailable

public static boolean isAvailable(String fullyQualifiedClassName)

newInstance

public static Object newInstance(String fqcn)

newInstance

public static Object newInstance(String fqcn,
 Object... args)

newInstance

public static Object newInstance(Class<?> clazz)

newInstance

public static Object newInstance(Class<?> clazz,
 Object... args)

getConstructor

public static Constructor<?> getConstructor(Class<?> clazz,
 Class<?>... argTypes)

instantiate

public static Object instantiate(Constructor<?> ctor,
 Object... args)

getAnnotatedMethods

public static List<Method> getAnnotatedMethods(Class<?> type,
 Class<? extends Annotation> annotation)

Parameters:

type -

annotation -

Returns:

Since:

1.3

setAdditionalClassLoader

public static void setAdditionalClassLoader(ClassLoader classLoader)

Sets additional ClassLoader for getResourceAsStream(String) and forName(String) to use It is used in addition to the thread context class loader and the system class loader.

Parameters:

classLoader - class loader to use

Since:

2.0.4

removeAdditionalClassLoader

public static void removeAdditionalClassLoader()

Removes the additional ClassLoader set by setAdditionalClassLoader(ClassLoader). This must be called to avoid memory leaks.

Since:

2.0.4