org.mule.util

Class ClassUtils

java.lang.Object

org.apache.commons.lang.ClassUtils

org.mule.util.ClassUtils

public class ClassUtils
extends org.apache.commons.lang.ClassUtils

Extend the Apache Commons ClassUtils to provide additional functionality.

This class is useful for loading resources and classes in a fault tolerant manner that works across different applications servers. The resource and classloading methods are SecurityManager friendly.

Field Summary

Fields

Modifier and Type	Field and Description
static Object[]	NO_ARGS
static Class<?>[]	NO_ARGS_TYPE

Fields inherited from class org.apache.commons.lang.ClassUtils

INNER_CLASS_SEPARATOR, INNER_CLASS_SEPARATOR_CHAR, PACKAGE_SEPARATOR, PACKAGE_SEPARATOR_CHAR

Constructor Summary

Constructors

Constructor and Description
ClassUtils()

Method Summary

Methods

Modifier and Type	Method and Description
static void	addLibrariesToClasspath(List urls)
static boolean	compare(Class[] c1, Class[] c2, boolean matchOnObject)
static boolean	compare(Class[] c1, Class[] c2, boolean matchOnObject, boolean acceptNulls) Returns true if the types from array c2 are assignable to the types from c1 and the arrays are the same size.
static boolean	equal(Object a, Object b) Simple helper for writing object equalities.
static String	getClassName(Class clazz)
static URL	getClassPathRoot(Class clazz)
static Class<?>[]	getClassTypes(Object object) Used for creating an array of class types for an array or single object
static Constructor	getConstructor(Class clazz, Class[] paramTypes)
static Constructor	getConstructor(Class clazz, Class[] paramTypes, boolean exactMatch) Returns available constructor in the target class that as the parameters specified.
static <T> T	getFieldValue(Object target, String fieldName, boolean recursive)
static Method	getMethod(Class<?> clazz, String name, Class<?>[] parameterTypes) Returns a matching method for the given name and parameters on the given class If the parameterTypes arguments is null it will return the first matching method on the class.
static Method	getMethod(Class clazz, String name, Class[] parameterTypes, boolean acceptNulls)
static Class<?>[]	getParameterTypes(Object bean, String methodName)
static URL	getResource(String resourceName, Class<?> callingClass) Load a given resource.
static Enumeration<URL>	getResources(String resourceName, Class<?> callingClass)
static List<Method>	getSatisfiableMethods(Class<?> implementation, Class<?>[] parameterTypes, boolean voidOk, boolean matchOnObject, Collection<String> ignoredMethodNames, WildcardFilter filter) A helper method that will find all matching methods on a class with the given parameter type
static List<Method>	getSatisfiableMethods(Class<?> implementation, Class<?>[] parameterTypes, boolean voidOk, boolean matchOnObject, Set<String> ignoredMethodNames) A helper method that will find all matching methods on a class with the given parameter type
static List<Method>	getSatisfiableMethodsWithReturnType(Class implementation, Class returnType, boolean matchOnObject, Set<String> ignoredMethodNames) Match all method son a class with a defined return type
static String	getSimpleName(Class clazz) Provide a simple-to-understand class name (with access to only Java 1.4 API).
static int	hash(Object[] state)
static Class<?>	initializeClass(Class<?> clazz) Ensure that the given class is properly initialized when the argument is passed in as .class literal.
static <T> T	instanciateClass(Class<? extends T> clazz, Object... constructorArgs)
static Object	instanciateClass(String name, Object... constructorArgs)
static Object	instanciateClass(String name, Object[] constructorArgs, Class<?> callingClass)
static Object	instanciateClass(String name, Object[] constructorArgs, ClassLoader classLoader)
static boolean	isClassOnPath(String className, Class currentClass) Can be used by serice endpoints to select which service to use based on what's loaded on the classpath
static boolean	isConcrete(Class<?> clazz)
static boolean	isConsumable(Class<?> payloadClass) Determines if the payload of this message is consumable i.e.
static <T> boolean	isInstance(Class<T> type, Object value) Checks that value is an instance of type.
static Class	loadClass(String className, Class<?> callingClass) Load a class with a given name.
static <T extends Class> T	loadClass(String className, Class<?> callingClass, T type) Load a class with a given name.
static Class	loadClass(String className, ClassLoader classLoader) Load a class with a given name from the given classloader.
static Class<? extends Annotation>	resolveAnnotationClass(Annotation annotation)
static void	setFieldValue(Object target, String fieldName, Object value, boolean recursive)
static Class[]	wrappersToPrimitives(Class[] wrappers)
static Class	wrapperToPrimitive(Class wrapper)

Methods inherited from class org.apache.commons.lang.ClassUtils

convertClassesToClassNames, convertClassNamesToClasses, getAllInterfaces, getAllSuperclasses, getClass, getClass, getClass, getClass, getPackageCanonicalName, getPackageCanonicalName, getPackageCanonicalName, getPackageName, getPackageName, getPackageName, getPublicMethod, getShortCanonicalName, getShortCanonicalName, getShortCanonicalName, getShortClassName, getShortClassName, getShortClassName, isAssignable, isAssignable, isInnerClass, primitivesToWrappers, primitiveToWrapper, toClass

Methods inherited from class java.lang.Object

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

Field Detail

NO_ARGS

public static final Object[] NO_ARGS

NO_ARGS_TYPE

public static final Class<?>[] NO_ARGS_TYPE

Constructor Detail

ClassUtils

public ClassUtils()

Method Detail

isConcrete

public static boolean isConcrete(Class<?> clazz)

getResource

public static URL getResource(String resourceName,
              Class<?> callingClass)

Load a given resource.

This method will try to load the resource using the following methods (in order):

• From Thread.currentThread().getContextClassLoader()
• From ClassUtils.class.getClassLoader()
• From the callingClass.getClassLoader()

Parameters:

resourceName - The name of the resource to load

callingClass - The Class object of the calling object

Returns:

A URL pointing to the resource to load or null if the resource is not found

getResources

public static Enumeration<URL> getResources(String resourceName,
                            Class<?> callingClass)

loadClass

public static Class loadClass(String className,
              Class<?> callingClass)
                       throws ClassNotFoundException

Load a class with a given name.

It will try to load the class in the following order:

• From Thread.currentThread().getContextClassLoader()
• Using the basic Class.forName(java.lang.String)
• From ClassLoaderUtil.class.getClassLoader()
• From the callingClass.getClassLoader()

Parameters:

className - The name of the class to load

callingClass - The Class object of the calling object

Returns:

The Class instance

Throws:

ClassNotFoundException - If the class cannot be found anywhere.

loadClass

public static <T extends Class> T loadClass(String className,
                            Class<?> callingClass,
                            T type)
                                 throws ClassNotFoundException

Load a class with a given name.

It will try to load the class in the following order:

• From Thread.currentThread().getContextClassLoader()
• Using the basic Class.forName(java.lang.String)
• From ClassLoaderUtil.class.getClassLoader()
• From the callingClass.getClassLoader()

Parameters:

className - The name of the class to load

callingClass - The Class object of the calling object

type - the class type to expect to load

Returns:

The Class instance

Throws:

ClassNotFoundException - If the class cannot be found anywhere.

loadClass

public static Class loadClass(String className,
              ClassLoader classLoader)
                       throws ClassNotFoundException

Load a class with a given name from the given classloader.

Parameters:

className - the name of the class to load

classLoader - the loader to load it from

Returns:

the instance of the class

Throws:

ClassNotFoundException - if the class is not available in the class loader

getFieldValue

public static <T> T getFieldValue(Object target,
                  String fieldName,
                  boolean recursive)
                       throws IllegalAccessException,
                              NoSuchFieldException

Throws:

IllegalAccessException

NoSuchFieldException

setFieldValue

public static void setFieldValue(Object target,
                 String fieldName,
                 Object value,
                 boolean recursive)
                          throws IllegalAccessException,
                                 NoSuchFieldException

Throws:

IllegalAccessException

NoSuchFieldException

initializeClass

public static Class<?> initializeClass(Class<?> clazz)

Ensure that the given class is properly initialized when the argument is passed in as .class literal. This method can never fail unless the bytecode is corrupted or the VM is otherwise seriously confused.

Parameters:

clazz - the Class to be initialized

Returns:

the same class but initialized

instanciateClass

public static <T> T instanciateClass(Class<? extends T> clazz,
                     Object... constructorArgs)
                          throws SecurityException,
                                 NoSuchMethodException,
                                 IllegalArgumentException,
                                 InstantiationException,
                                 IllegalAccessException,
                                 InvocationTargetException

Throws:

SecurityException

NoSuchMethodException

IllegalArgumentException

InstantiationException

IllegalAccessException

InvocationTargetException

instanciateClass

public static Object instanciateClass(String name,
                      Object... constructorArgs)
                               throws ClassNotFoundException,
                                      SecurityException,
                                      NoSuchMethodException,
                                      IllegalArgumentException,
                                      InstantiationException,
                                      IllegalAccessException,
                                      InvocationTargetException

Throws:

ClassNotFoundException

SecurityException

NoSuchMethodException

IllegalArgumentException

InstantiationException

IllegalAccessException

InvocationTargetException

instanciateClass

public static Object instanciateClass(String name,
                      Object[] constructorArgs,
                      Class<?> callingClass)
                               throws ClassNotFoundException,
                                      SecurityException,
                                      NoSuchMethodException,
                                      IllegalArgumentException,
                                      InstantiationException,
                                      IllegalAccessException,
                                      InvocationTargetException

Throws:

ClassNotFoundException

SecurityException

NoSuchMethodException

IllegalArgumentException

InstantiationException

IllegalAccessException

InvocationTargetException

instanciateClass

public static Object instanciateClass(String name,
                      Object[] constructorArgs,
                      ClassLoader classLoader)
                               throws ClassNotFoundException,
                                      SecurityException,
                                      NoSuchMethodException,
                                      IllegalArgumentException,
                                      InstantiationException,
                                      IllegalAccessException,
                                      InvocationTargetException

Throws:

ClassNotFoundException

SecurityException

NoSuchMethodException

IllegalArgumentException

InstantiationException

IllegalAccessException

InvocationTargetException

getParameterTypes

public static Class<?>[] getParameterTypes(Object bean,
                           String methodName)

getMethod

public static Method getMethod(Class<?> clazz,
               String name,
               Class<?>[] parameterTypes)

Returns a matching method for the given name and parameters on the given class If the parameterTypes arguments is null it will return the first matching method on the class.

Parameters:

clazz - the class to find the method on

name - the method name to find

parameterTypes - an array of argument types or null

Returns:

the Method object or null if none was found

getMethod

public static Method getMethod(Class clazz,
               String name,
               Class[] parameterTypes,
               boolean acceptNulls)

getConstructor

public static Constructor getConstructor(Class clazz,
                         Class[] paramTypes)

getConstructor

public static Constructor getConstructor(Class clazz,
                         Class[] paramTypes,
                         boolean exactMatch)

Returns available constructor in the target class that as the parameters specified.

Parameters:

clazz - the class to search

paramTypes - the param types to match against

exactMatch - should exact types be used (i.e. equals rather than isAssignableFrom.)

Returns:

The matching constructor or null if no matching constructor is found

getSatisfiableMethods

public static List<Method> getSatisfiableMethods(Class<?> implementation,
                                 Class<?>[] parameterTypes,
                                 boolean voidOk,
                                 boolean matchOnObject,
                                 Set<String> ignoredMethodNames)

A helper method that will find all matching methods on a class with the given parameter type

Parameters:

implementation - the class to build methods on

parameterTypes - the argument param types to look for

voidOk - whether void methods shouldbe included in the found list

matchOnObject - determines whether parameters of Object type are matched when they are of Object.class type

ignoredMethodNames - a Set of method names to ignore. Often 'equals' is not a desired match. This argument can be null.

Returns:

a List of methods on the class that match the criteria. If there are none, an empty list is returned

getSatisfiableMethods

public static List<Method> getSatisfiableMethods(Class<?> implementation,
                                 Class<?>[] parameterTypes,
                                 boolean voidOk,
                                 boolean matchOnObject,
                                 Collection<String> ignoredMethodNames,
                                 WildcardFilter filter)

A helper method that will find all matching methods on a class with the given parameter type

Parameters:

implementation - the class to build methods on

parameterTypes - the argument param types to look for

voidOk - whether void methods shouldbe included in the found list

matchOnObject - determines whether parameters of Object type are matched when they are of Object.class type

ignoredMethodNames - a Set of method names to ignore. Often 'equals' is not a desired match. This argument can be null.

filter - Wildcard expression filter that allows methods to be matched using wildcards i.e. 'get*'

Returns:

a List of methods on the class that match the criteria. If there are none, an empty list is returned

getSatisfiableMethodsWithReturnType

public static List<Method> getSatisfiableMethodsWithReturnType(Class implementation,
                                               Class returnType,
                                               boolean matchOnObject,
                                               Set<String> ignoredMethodNames)

Match all method son a class with a defined return type

Parameters:

implementation - the class to search

returnType - the return type to match

matchOnObject - whether Object methods should be matched

ignoredMethodNames - a set of method names to ignore

Returns:

the list of methods that matched the return type and criteria. If none are found an empty result is returned

isClassOnPath

public static boolean isClassOnPath(String className,
                    Class currentClass)

Can be used by serice endpoints to select which service to use based on what's loaded on the classpath

Parameters:

className - The class name to look for

currentClass - the calling class

Returns:

true if the class is on the path

getClassTypes

public static Class<?>[] getClassTypes(Object object)

Used for creating an array of class types for an array or single object

Parameters:

object - single object or array. If this parameter is null or a zero length array then NO_ARGS_TYPE is returned

Returns:

an array of class types for the object

getClassName

public static String getClassName(Class clazz)

compare

public static boolean compare(Class[] c1,
              Class[] c2,
              boolean matchOnObject)

compare

public static boolean compare(Class[] c1,
              Class[] c2,
              boolean matchOnObject,
              boolean acceptNulls)

Returns true if the types from array c2 are assignable to the types from c1 and the arrays are the same size. If matchOnObject argument is true and there is a parameter of type Object in c1 then the method returns false. If acceptNulls argument is true, null values are accepted in c2.

Parameters:

c1 - parameter types array

c2 - parameter types array

matchOnObject - return false if there is a parameter of type Object in c1

acceptNulls - allows null parameter types in c2

Returns:

true if arrays are the same size and the types assignable from c2 to c1

wrapperToPrimitive

public static Class wrapperToPrimitive(Class wrapper)

wrappersToPrimitives

public static Class[] wrappersToPrimitives(Class[] wrappers)

getSimpleName

public static String getSimpleName(Class clazz)

Provide a simple-to-understand class name (with access to only Java 1.4 API).

Parameters:

clazz - The class whose name we will generate

Returns:

A readable name for the class

equal

public static boolean equal(Object a,
            Object b)

Simple helper for writing object equalities. TODO Is there a better place for this?

Parameters:

a - object to compare

b - object to be compared to

Returns:

true if the objects are equal (value or reference), false otherwise

hash

public static int hash(Object[] state)

addLibrariesToClasspath

public static void addLibrariesToClasspath(List urls)
                                    throws NoSuchMethodException,
                                           IllegalAccessException,
                                           InvocationTargetException

Throws:

NoSuchMethodException

IllegalAccessException

InvocationTargetException

getClassPathRoot

public static URL getClassPathRoot(Class clazz)

resolveAnnotationClass

public static Class<? extends Annotation> resolveAnnotationClass(Annotation annotation)

isInstance

public static <T> boolean isInstance(Class<T> type,
                     Object value)

Checks that value is an instance of type.

The value that this method adds over something like Class.isInstance(Object) is that it also considers the case in which type and value are evaluate by isWrapperAndPrimitivePair(Class, Class) as true

Type Parameters:

T - the generic type of type

Parameters:

type - the Class you want to check the value against

value - an instance you want to verify is instance of type

Returns:

true if value is an instance of type or if they are a wrapper-primitive pair. false otherwise

isConsumable

public static boolean isConsumable(Class<?> payloadClass)

Determines if the payload of this message is consumable i.e. it can't be read more than once.