org.jboss.modules

Class Module

java.lang.Object

org.jboss.modules.Module

public final class Module
extends Object

A module is a unit of classes and other resources, along with the specification of what is imported and exported by this module from and to other modules. Modules are created by ModuleLoaders which build modules from various configuration information and resource roots.

Author:

David M. Lloyd, John Bailey, Flavia Rainone, Jason T. Greene, thomas.diesler@jboss.com

Method Summary

Modifier and Type	Method and Description
static Module	forClass(Class<?> clazz) Get the module for a loaded class, or null if the class did not come from any module.
static Module	forClassLoader(ClassLoader cl, boolean search) Get the module for a class loader, or null if the class loader is not associated with any module.
static ModuleLoader	getBootModuleLoader() Gets the boot module loader.
static Module	getCallerModule() Get the caller's module.
static ModuleLoader	getCallerModuleLoader() Gets the current module loader.
ModuleClassLoader	getClassLoader() Get the class loader for a module.
static ModuleLoader	getContextModuleLoader() Get the current thread's context module loader.
DependencySpec[]	getDependencies() Get the current dependencies of this module.
Set<String>	getExportedPaths() Get all the paths exported by this module.
URL	getExportedResource(String name) Get an exported resource URL.
Resource	getExportedResource(String rootPath, String resourcePath) Get an exported resource from a specific root in this module.
Enumeration<URL>	getExportedResources(String name) Get all exported resource URLs for a resource name.
ModuleIdentifier	getIdentifier() Get this module's identifier.
Set<String>	getImportedPaths() Get the (unmodifiable) set of paths which are imported into this module class loader, including local paths.
Module	getModule(ModuleIdentifier identifier) Get the module with the given identifier from the module loader used by this module.
static Module	getModuleFromCallerModuleLoader(ModuleIdentifier identifier) Get a module from the current module loader.
ModuleLoader	getModuleLoader() Get the module loader which created this module.
static ModuleLogger	getModuleLogger() Get the logger used by the module system.
static String	getPlatformIdentifier() Get the platform identifier.
static ModulesPrivateAccess	getPrivateAccess() Private access for module internal code.
String	getProperty(String name) Get the property with the given name, or null if none was defined.
String	getProperty(String name, String defaultVal) Get the property with the given name, or a default value if none was defined.
List<String>	getPropertyNames() Get a copy of the list of property names.
static long	getStartTime() Return the start time in millis when Module.class was loaded.
Iterator<Resource>	globResources(String glob) Enumerate all imported resources in this module which match the given glob expression.
Iterator<Resource>	iterateResources(PathFilter filter) Enumerate all the imported resources in this module, subject to a path filter.
static Class<?>	loadClassFromBootModuleLoader(ModuleIdentifier moduleIdentifier, String className) Load a class from a module in the system module loader.
static Class<?>	loadClassFromCallerModuleLoader(ModuleIdentifier moduleIdentifier, String className) Load a class from a module in the caller's module loader.
<S> ServiceLoader<S>	loadService(Class<S> serviceType) Load a service loader from this module.
static <S> ServiceLoader<S>	loadServiceFromCallerModuleLoader(ModuleIdentifier identifier, Class<S> serviceType) Load a service loader from a module in the caller's module loader.
static void	registerContentHandlerFactoryModule(Module module) Register an additional module which contains content handlers.
static void	registerURLStreamHandlerFactoryModule(Module module) Register an additional module which contains URL handlers.
void	run(String[] args) Run a module's main class, if any.
static void	setModuleLogger(ModuleLogger logger) Change the logger used by the module system.
String	toString() Get the string representation of this module.

Methods inherited from class java.lang.Object

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

Method Detail

getPrivateAccess

public static ModulesPrivateAccess getPrivateAccess()

Private access for module internal code. Throws SecurityException for user code.

Throws:

SecurityException - always

getDependencies

public DependencySpec[] getDependencies()
                                 throws SecurityException

Get the current dependencies of this module.

Returns:

the current dependencies of this module

Throws:

SecurityException - if a security manager is enabled and the caller does not have the getDependencies RuntimePermission

getExportedResource

public Resource getExportedResource(String rootPath,
                                    String resourcePath)

Get an exported resource from a specific root in this module.

Parameters:

rootPath - the module root to search

resourcePath - the path of the resource

Returns:

the resource

run

public void run(String[] args)
         throws NoSuchMethodException,
                InvocationTargetException,
                ClassNotFoundException

Run a module's main class, if any.

Parameters:

args - the arguments to pass

Throws:

NoSuchMethodException - if there is no main method

InvocationTargetException - if the main method failed

ClassNotFoundException - if the main class is not found

getIdentifier

public ModuleIdentifier getIdentifier()

Get this module's identifier.

Returns:

the identifier

getModuleLoader

public ModuleLoader getModuleLoader()

Get the module loader which created this module.

Returns:

the module loader of this module

loadService

public <S> ServiceLoader<S> loadService(Class<S> serviceType)

Load a service loader from this module.

Type Parameters:

S - the service type

Parameters:

serviceType - the service type class

Returns:

the service loader

loadServiceFromCallerModuleLoader

public static <S> ServiceLoader<S> loadServiceFromCallerModuleLoader(ModuleIdentifier identifier,
                                                                     Class<S> serviceType)
                                                              throws ModuleLoadException

Load a service loader from a module in the caller's module loader. The caller's module loader refers to the loader of the module of the class that calls this method. Note that loadService(Class) is more efficient since it does not need to crawl the stack.

Type Parameters:

S - the the service type

Parameters:

identifier - the module identifier containing the service loader

serviceType - the service type class

Returns:

the loaded service from the caller's module

Throws:

ModuleLoadException - if the named module failed to load

getClassLoader

public ModuleClassLoader getClassLoader()

Get the class loader for a module. The class loader can be used to access non-exported classes and resources of the module.

If a security manager is present, then this method invokes the security manager's checkPermission method with a RuntimePermission("getClassLoader") permission to verify access to the class loader. If access is not granted, a SecurityException will be thrown.

Returns:

the module class loader

getExportedPaths

public Set<String> getExportedPaths()

Get all the paths exported by this module.

Returns:

the paths that are exported by this module

forClass

public static Module forClass(Class<?> clazz)

Get the module for a loaded class, or null if the class did not come from any module.

Parameters:

clazz - the class

Returns:

the module it came from

forClassLoader

public static Module forClassLoader(ClassLoader cl,
                                    boolean search)

Get the module for a class loader, or null if the class loader is not associated with any module. If the class loader is unknown, it is possible to check the parent class loader up the chain, and so on until a module is found.

Parameters:

cl - the class loader

search - true to search up the delegation chain

Returns:

the associated module

getBootModuleLoader

public static ModuleLoader getBootModuleLoader()

Gets the boot module loader. The boot module loader is the initial loader that is established by the module framework. It typically is based off of the environmental module path unless it is overridden by specifying a different class name for the boot.module.loader system property.

Returns:

the boot module loader

getCallerModuleLoader

public static ModuleLoader getCallerModuleLoader()

Gets the current module loader. The current module loader is the loader of the module from the calling class. Note that this method must crawl the stack to determine this, so other mechanisms are more efficient.

Returns:

the current module loader, or null if this method is called outside of a module

getContextModuleLoader

public static ModuleLoader getContextModuleLoader()

Get the current thread's context module loader. This loader is the one which defined the module whose class loader is, or is a parent of, the thread's current context class loader. If there is none, then null is returned.

Returns:

the module loader, or null if none is set

getModuleFromCallerModuleLoader

public static Module getModuleFromCallerModuleLoader(ModuleIdentifier identifier)
                                              throws ModuleLoadException

Get a module from the current module loader. Note that this must crawl the stack to determine this, so other mechanisms are more efficient.

Parameters:

identifier - the module identifier

Returns:

the module

Throws:

ModuleLoadException - if the module could not be loaded

See Also:

getCallerModuleLoader()

getCallerModule

public static Module getCallerModule()

Get the caller's module. The caller's module is the module containing the method that calls this method. Note that this method crawls the stack so other ways of obtaining the module are more efficient.

Returns:

the current module

getModule

public Module getModule(ModuleIdentifier identifier)
                 throws ModuleLoadException

Get the module with the given identifier from the module loader used by this module.

Parameters:

identifier - the module identifier

Returns:

the module

Throws:

ModuleLoadException - if an error occurs

loadClassFromBootModuleLoader

public static Class<?> loadClassFromBootModuleLoader(ModuleIdentifier moduleIdentifier,
                                                     String className)
                                              throws ModuleLoadException,
                                                     ClassNotFoundException

Load a class from a module in the system module loader.

Parameters:

moduleIdentifier - the identifier of the module from which the class should be loaded

className - the class name to load

Returns:

the class

Throws:

ModuleLoadException - if the module could not be loaded

ClassNotFoundException - if the class could not be loaded

See Also:

getBootModuleLoader()

loadClassFromCallerModuleLoader

public static Class<?> loadClassFromCallerModuleLoader(ModuleIdentifier moduleIdentifier,
                                                       String className)
                                                throws ModuleLoadException,
                                                       ClassNotFoundException

Load a class from a module in the caller's module loader.

Parameters:

moduleIdentifier - the identifier of the module from which the class should be loaded

className - the class name to load

Returns:

the class

Throws:

ModuleLoadException - if the module could not be loaded

ClassNotFoundException - if the class could not be loaded

See Also:

getCallerModuleLoader()

getExportedResource

public URL getExportedResource(String name)

Get an exported resource URL.

Parameters:

name - the resource name

Returns:

the resource, or null if it was not found

getExportedResources

public Enumeration<URL> getExportedResources(String name)

Get all exported resource URLs for a resource name.

Parameters:

name - the resource name

Returns:

the resource URLs

iterateResources

public Iterator<Resource> iterateResources(PathFilter filter)
                                    throws ModuleLoadException

Enumerate all the imported resources in this module, subject to a path filter. The filter applies to the containing path of each resource.

Parameters:

filter - the filter to apply to the search

Returns:

the resource iterator (possibly empty)

Throws:

ModuleLoadException - if linking a dependency module fails for some reason

globResources

public Iterator<Resource> globResources(String glob)
                                 throws ModuleLoadException

Enumerate all imported resources in this module which match the given glob expression. The glob applies to the whole resource name.

Parameters:

glob - the glob to apply

Returns:

the iterator

Throws:

ModuleLoadException - if linking a dependency module fails for some reason

getImportedPaths

public final Set<String> getImportedPaths()
                                   throws ModuleLoadException

Get the (unmodifiable) set of paths which are imported into this module class loader, including local paths. The set will include all paths defined by the module's resource loaders, minus any paths excluded by filters. The set will generally always contain an empty entry (""). The set is unordered and unsorted, and is iterable in O(n) time and accessible in O(1) time.

Returns:

the set of paths

Throws:

ModuleLoadException - if the module was previously unlinked, and there was an exception while linking

getProperty

public String getProperty(String name)

Get the property with the given name, or null if none was defined.

Parameters:

name - the property name

Returns:

the property value

getProperty

public String getProperty(String name,
                          String defaultVal)

Get the property with the given name, or a default value if none was defined.

Parameters:

name - the property name

defaultVal - the default value

Returns:

the property value

getPropertyNames

public List<String> getPropertyNames()

Get a copy of the list of property names.

Returns:

the property names list

toString

public String toString()

Get the string representation of this module.

Overrides:

toString in class Object

Returns:

the string representation

getModuleLogger

public static ModuleLogger getModuleLogger()

Get the logger used by the module system.

If a security manager is present, then this method invokes the security manager's checkPermission method with a RuntimePermission("accessModuleLogger") permission to verify access to the module logger. If access is not granted, a SecurityException will be thrown.

Returns:

the module logger

setModuleLogger

public static void setModuleLogger(ModuleLogger logger)

Change the logger used by the module system.

If a security manager is present, then this method invokes the security manager's checkPermission method with a RuntimePermission("accessModuleLogger") permission to verify access to the module logger. If access is not granted, a SecurityException will be thrown.

Parameters:

logger - the new logger, must not be null

getStartTime

public static long getStartTime()

Return the start time in millis when Module.class was loaded.

Returns:

start time of Module.class load

registerContentHandlerFactoryModule

public static void registerContentHandlerFactoryModule(Module module)

Register an additional module which contains content handlers.

If a security manager is present, then this method invokes the security manager's checkPermission method with a RuntimePermission("addContentHandlerFactory") permission to verify access. If access is not granted, a SecurityException will be thrown.

Parameters:

module - the module to add

registerURLStreamHandlerFactoryModule

public static void registerURLStreamHandlerFactoryModule(Module module)

Register an additional module which contains URL handlers.

If a security manager is present, then this method invokes the security manager's checkPermission method with a RuntimePermission("addURLStreamHandlerFactory") permission to verify access. If access is not granted, a SecurityException will be thrown.

Parameters:

module - the module to add

getPlatformIdentifier

public static String getPlatformIdentifier()

Get the platform identifier. This is the string that uniquely identifies the hardware and OS combination for the current running system.

Returns:

the platform identifier