org.apache.deltaspike.core.util

Class ClassUtils

java.lang.Object

org.apache.deltaspike.core.util.ClassUtils

@Typed
public abstract class ClassUtils
extends Object

Util methods for classes, ClassLoader and Manifest handling

Method Summary

Modifier and Type	Method and Description
static boolean	containsMethod(Class<?> targetClass, Method method) Checks if the given class contains a method with the same signature.
static boolean	containsPossiblyGenericMethod(Class<?> targetClass, Method method) Checks if the given class has a method with the same signature, taking in to account generic types
static Method	extractMethod(Class<?> clazz, Method sourceMethod) Extracts a method with same signature as the source method.
static Method	extractPossiblyGenericMethod(Class<?> clazz, Method sourceMethod) Extracts a method matching the source method, allowing generic type parameters to be substituted as long as they are properly castable.
static ClassLoader	getClassLoader(Object o) Detect the right ClassLoader.
static String	getJarVersion(Class targetClass) Reads the version of the jar which contains the given class
static String	getRevision(Class targetClass) Reads the VCS revision which was used for creating the jar
static Object	instantiateClassForName(String className) Creates an instance for the given class-name
static Class	loadClassForName(String name) Loads class for the given name
static <T> T	tryToInstantiateClass(Class<T> targetClass) Instantiates a given class via the default constructor
static Object	tryToInstantiateClassForName(String className) Tries to instantiate a class for the given name via the default constructor
static <T> T	tryToInstantiateClassForName(String className, Class<T> targetType) Tries to instantiate a class for the given name and type via the default constructor
static Class	tryToLoadClassForName(String name) Tries to load a class based on the given name
static <T> Class<T>	tryToLoadClassForName(String name, Class<T> targetType) Tries to load a class based on the given name and interface or abstract class.
static <T> Class<T>	tryToLoadClassForName(String name, Class<T> targetType, ClassLoader classLoader) Tries to load a class based on the given name and interface or abstract class.
static Class	tryToLoadClassForName(String name, ClassLoader classLoader) Tries to load a class based on the given name

Methods inherited from class java.lang.Object

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

Method Detail

getClassLoader

public static ClassLoader getClassLoader(Object o)

Detect the right ClassLoader. The lookup order is determined by:

1. ContextClassLoader of the current Thread
2. ClassLoader of the given Object 'o'
3. ClassLoader of this very ClassUtils class

Parameters:

o - if not null it may get used to detect the classloader.

Returns:

The ClassLoader which should get used to create new instances

tryToLoadClassForName

public static <T> Class<T> tryToLoadClassForName(String name,
                                                 Class<T> targetType)

Tries to load a class based on the given name and interface or abstract class.

Type Parameters:

T - current type

Parameters:

name - name of the concrete class

targetType - target type (interface or abstract class)

Returns:

loaded class or null if it isn't in the classpath

tryToLoadClassForName

public static <T> Class<T> tryToLoadClassForName(String name,
                                                 Class<T> targetType,
                                                 ClassLoader classLoader)

Tries to load a class based on the given name and interface or abstract class.

Type Parameters:

T - current type

Parameters:

name - name of the concrete class

targetType - target type (interface or abstract class)

classLoader - The ClassLoader.

Returns:

loaded class or null if it isn't in the classpath

tryToLoadClassForName

public static Class tryToLoadClassForName(String name)

Tries to load a class based on the given name

Parameters:

name - name of the class

Returns:

loaded class or null if it isn't in the classpath

tryToLoadClassForName

public static Class tryToLoadClassForName(String name,
                                          ClassLoader classLoader)

Tries to load a class based on the given name

Parameters:

name - name of the class

classLoader - The ClassLoader.

Returns:

loaded class or null if it isn't in the classpath

loadClassForName

public static Class loadClassForName(String name)
                              throws ClassNotFoundException

Loads class for the given name

Parameters:

name - name of the class

Returns:

loaded class

Throws:

ClassNotFoundException - if the class can't be loaded

tryToInstantiateClass

public static <T> T tryToInstantiateClass(Class<T> targetClass)

Instantiates a given class via the default constructor

Type Parameters:

T - current type

Parameters:

targetClass - class which should be instantiated

Returns:

created instance or null if the instantiation failed

tryToInstantiateClassForName

public static <T> T tryToInstantiateClassForName(String className,
                                                 Class<T> targetType)

Tries to instantiate a class for the given name and type via the default constructor

Type Parameters:

T - current type

Parameters:

className - name of the class

targetType - target type

Returns:

created instance or null if the instantiation failed

tryToInstantiateClassForName

public static Object tryToInstantiateClassForName(String className)

Tries to instantiate a class for the given name via the default constructor

Parameters:

className - name of the class

Returns:

created instance or null if the instantiation failed

instantiateClassForName

public static Object instantiateClassForName(String className)
                                      throws ClassNotFoundException,
                                             IllegalAccessException,
                                             InstantiationException

Creates an instance for the given class-name

Parameters:

className - name of the class which should be instantiated

Returns:

created instance

Throws:

ClassNotFoundException - if the instantiation failed

IllegalAccessException - if the instantiation failed

InstantiationException - if the instantiation failed

getJarVersion

public static String getJarVersion(Class targetClass)

Reads the version of the jar which contains the given class

Parameters:

targetClass - class within the jar

Returns:

version-string which has been found in the manifest or null if there is no version information available

getRevision

public static String getRevision(Class targetClass)

Reads the VCS revision which was used for creating the jar

Parameters:

targetClass - class within the jar

Returns:

revision-string which has been found in the manifest or null if there is no information available

containsMethod

public static boolean containsMethod(Class<?> targetClass,
                                     Method method)

Checks if the given class contains a method with the same signature.

Parameters:

targetClass - The class to check

method - The source method

Returns:

if it contains a method with the same signature.

extractMethod

public static Method extractMethod(Class<?> clazz,
                                   Method sourceMethod)

Extracts a method with same signature as the source method.

Parameters:

clazz - The target class

sourceMethod - The source method.

Returns:

the extracted method or null

containsPossiblyGenericMethod

public static boolean containsPossiblyGenericMethod(Class<?> targetClass,
                                                    Method method)

Checks if the given class has a method with the same signature, taking in to account generic types

Parameters:

targetClass -

method -

Returns:

if it contains a method with the same signature.

extractPossiblyGenericMethod

public static Method extractPossiblyGenericMethod(Class<?> clazz,
                                                  Method sourceMethod)

Extracts a method matching the source method, allowing generic type parameters to be substituted as long as they are properly castable.

Parameters:

clazz - The target class

sourceMethod - The source method.

Returns:

the extracted method or null