Class ModuleLoader

    • Field Detail

      • NO_FINDERS

        public static final ModuleFinder[] NO_FINDERS
        A constant representing zero module finders.
    • Constructor Detail

      • ModuleLoader

        protected ModuleLoader()
        Construct a new instance.
      • ModuleLoader

        public ModuleLoader​(ModuleFinder[] finders)
        Construct a new instance.
        Parameters:
        finders - the module finders to search, in order
      • ModuleLoader

        public ModuleLoader​(ModuleFinder finder)
        Construct a new instance.
        Parameters:
        finder - the single module finder to search (must not be null)
    • Method Detail

      • forClass

        public static ModuleLoader forClass​(java.lang.Class<?> clazz)
        Get the module loader for a class.
        Parameters:
        clazz - the class
        Returns:
        the module loader or null if the class's class loader does not belong to a module loader.
      • forClassLoader

        public static ModuleLoader forClassLoader​(java.lang.ClassLoader classLoader)
        Get the module loader for a class loader.
        Parameters:
        classLoader - the class loader
        Returns:
        the module loader or null if the class loader does not belong to a module loader.
      • toString

        public java.lang.String toString()
        Get the string representation of this module loader.
        Overrides:
        toString in class java.lang.Object
        Returns:
        the string representation
      • getModuleDescription

        public java.lang.String getModuleDescription​(Module module)
        Get a string representation of the given module, used in debug output and stack traces. This method may be overridden to provide a more detailed description. By default it returns a string consisting of the module's name and version (if any).
        Parameters:
        module - the module to describe
        Returns:
        the description string
      • installMBeanServer

        public static void installMBeanServer()
        Install JBoss Modules MBeans. WARNING: This method is not intended to be called by application code.
      • loadModule

        public final Module loadModule​(java.lang.String name)
                                throws ModuleLoadException
        Load a module based on an identifier. This method delegates to preloadModule(String) and then links the returned module if necessary.
        Parameters:
        name - The module name
        Returns:
        The loaded Module
        Throws:
        ModuleLoadException - if the Module can not be loaded
      • iterateModules

        @Deprecated
        public final java.util.Iterator<ModuleIdentifier> iterateModules​(ModuleIdentifier baseIdentifier,
                                                                         boolean recursive)
        Deprecated.
        Iterate the modules which can be located via this module loader.
        Parameters:
        baseIdentifier - the identifier to start with, or null to iterate all modules
        recursive - true to find recursively nested modules, false to only find immediately nested modules
        Returns:
        an iterator for the modules in this module finder
        Throws:
        java.lang.SecurityException - if the caller does not have permission to iterate module loaders
      • iterateModules

        public final java.util.Iterator<java.lang.String> iterateModules​(java.lang.String baseName,
                                                                         boolean recursive)
        Iterate the modules which can be located via this module loader.
        Parameters:
        baseName - the identifier to start with, or null to iterate all modules; ignored if this module loader does not have a concept of nested modules
        recursive - true to find recursively nested modules, false to only find immediately nested modules; ignored if this module finder does not have a concept of nested modules
        Returns:
        an iterator for the modules in this module finder
        Throws:
        java.lang.SecurityException - if the caller does not have permission to iterate module loaders
      • preloadModule

        @Deprecated
        protected Module preloadModule​(ModuleIdentifier identifier)
                                throws ModuleLoadException
        Deprecated.
        This compatibility method just calls preloadModule(methodIdentifier.toString()) and is usually not used; if however a legacy subclass overrides this method, then it will be called instead of preloadModule(String), and that method will redirect to this one.
        Parameters:
        identifier - the module identifier (must not be null)
        Returns:
        the load result, or null if the module is not found
        Throws:
        ModuleLoadException - if an error occurs
      • preloadModule

        protected Module preloadModule​(java.lang.String name)
                                throws ModuleLoadException
        Preload a module based on an identifier. By default, delegation is only done for system and this method otherwise simply invokes loadModuleLocal(String). A delegating module loader may delegate to the appropriate module loader based on loader-specific criteria (via the preloadModule(String, ModuleLoader) method).
        Parameters:
        name - the module identifier
        Returns:
        the load result, or null if the module is not found
        Throws:
        ModuleLoadException - if an error occurs
      • preloadExportedModule

        protected Module preloadExportedModule​(java.lang.String name)
                                        throws ModuleLoadException
        Preload an "exported" module based on an identifier. By default this simply delegates to preloadModule(String).
        Parameters:
        name - the module name
        Returns:
        the load result, or null if the module is not found
        Throws:
        ModuleLoadException - if an error occurs
      • preloadModule

        protected static Module preloadModule​(java.lang.String name,
                                              ModuleLoader moduleLoader)
                                       throws ModuleLoadException
        Utility method to delegate to another module loader, accessible from subclasses. The delegate module loader will be queried for exported modules only.
        Parameters:
        name - the module name
        moduleLoader - the module loader to delegate to
        Returns:
        the delegation result
        Throws:
        ModuleLoadException - if an error occurs
      • preloadModule

        @Deprecated
        protected static Module preloadModule​(ModuleIdentifier identifier,
                                              ModuleLoader moduleLoader)
                                       throws ModuleLoadException
        Deprecated.
        Utility method to delegate to another module loader, accessible from subclasses. The delegate module loader will be queried for exported modules only.
        Parameters:
        identifier - the module identifier
        moduleLoader - the module loader to delegate to
        Returns:
        the delegation result
        Throws:
        ModuleLoadException - if an error occurs
      • loadModuleLocal

        @Deprecated
        protected final Module loadModuleLocal​(ModuleIdentifier moduleIdentifier)
                                        throws ModuleLoadException
        Deprecated.
        Try to load a module from this module loader. Returns null if the module is not found. The returned module may not yet be resolved. The returned module may have a different name than the given identifier if the identifier is an alias for another module.
        Parameters:
        moduleIdentifier - the module identifier
        Returns:
        the module
        Throws:
        ModuleLoadException - if an error occurs while loading the module
      • loadModuleLocal

        protected final Module loadModuleLocal​(java.lang.String name)
                                        throws ModuleLoadException
        Try to load a module from this module loader. Returns null if the module is not found. The returned module may not yet be resolved. The returned module may have a different name than the given identifier if the identifier is an alias for another module.
        Parameters:
        name - the module name
        Returns:
        the module
        Throws:
        ModuleLoadException - if an error occurs while loading the module
      • findLoadedModuleLocal

        @Deprecated
        protected final Module findLoadedModuleLocal​(ModuleIdentifier identifier)
        Deprecated.
        Find an already-loaded module, returning null if the module isn't currently loaded. May block while the loaded state of the module is in question (if the module is being concurrently loaded from another thread, for example).
        Parameters:
        identifier - the module identifier
        Returns:
        the module, or null if it wasn't found
      • findLoadedModuleLocal

        protected final Module findLoadedModuleLocal​(java.lang.String name)
        Find an already-loaded module, returning null if the module isn't currently loaded. May block while the loaded state of the module is in question (if the module is being concurrently loaded from another thread, for example).
        Parameters:
        name - the module identifier
        Returns:
        the module, or null if it wasn't found
      • unloadModuleLocal

        @Deprecated
        protected final void unloadModuleLocal​(Module module)
                                        throws java.lang.SecurityException
        Deprecated.
        Unload a module from this module loader. Note that this has no effect on existing modules which refer to the module being unloaded. Also, only modules from the current module loader can be unloaded. Unloading the same module more than once has no additional effect. This method only removes the mapping for the module; any running threads which are currently accessing or linked to the module will continue to function, however attempts to load this module will fail until a new module is loaded with the same name. Once this happens, if all references to the previous module are not cleared, the same module may be loaded more than once, causing possible class duplication and class cast exceptions if proper care is not taken.
        Parameters:
        module - the module to unload
        Throws:
        java.lang.SecurityException - if an attempt is made to unload a module which does not belong to this module loader
        java.lang.SecurityException - if the module was not defined by this module loader
      • unloadModuleLocal

        protected final boolean unloadModuleLocal​(java.lang.String moduleId,
                                                  Module module)
                                           throws java.lang.SecurityException
        Unload a module from this module loader. Note that this has no effect on existing modules which refer to the module being unloaded. Also, only modules from the current module loader can be unloaded. Unloading the same module more than once has no additional effect. This method only removes the mapping for the module; any running threads which are currently accessing or linked to the module will continue to function, however attempts to load this module will fail until a new module is loaded with the same name. Once this happens, if all references to the previous module are not cleared, the same module may be loaded more than once, causing possible class duplication and class cast exceptions if proper care is not taken. If the given moduleName is an alias of the given module then only alias mapping to module is removed. Aliased module with its canonical name and other aliases mapping is left intact. If the given moduleName is the canonical module name then all its alias plus canonical moduleName association mappings are removed.
        Parameters:
        moduleId - the module identifier
        module - the module to unload
        Returns:
        true iff module was unloaded
        Throws:
        java.lang.SecurityException - if an attempt is made to unload a module which does not belong to this module loader
        java.lang.SecurityException - if the module was not defined by this module loader
      • findModule

        @Deprecated
        protected ModuleSpec findModule​(ModuleIdentifier moduleIdentifier)
                                 throws ModuleLoadException
        Deprecated.
        Use findModule(String) instead.
        This compatibility method just calls findModule(methodIdentifier.toString()) and is usually not used; if however a legacy subclass overrides this method, then it will be called instead of findModule(String), and that method will redirect to this one.
        Parameters:
        moduleIdentifier - the module identifier
        Returns:
        the module specification
        Throws:
        ModuleLoadException
      • findModule

        protected ModuleSpec findModule​(java.lang.String name)
                                 throws ModuleLoadException
        Find a Module's specification in this ModuleLoader by its name. This can be overriden by sub-classes to implement the Module loading strategy for this loader. The default implementation iterates the module finders provided during construction.

        If no module is found in this module loader with the given identifier, then this method should return null. If the module is found but some problem occurred (for example, a transitive dependency failed to load) then this method should throw a ModuleLoadException of the relevant type.

        Parameters:
        name - the module name
        Returns:
        the module specification, or null if no module is found with the given identifier
        Throws:
        ModuleLoadException - if any problems occur finding the module
      • getFinders

        protected final ModuleFinder[] getFinders()
        Get the module finders configured for this module loader.
        Returns:
        the module finders
      • refreshResourceLoaders

        protected void refreshResourceLoaders​(Module module)
        Refreshes the paths provided by resource loaders associated with the specified Module. This is an advanced method that is intended to be called on modules that have a resource loader implementation that has changed and is returning different paths.
        Parameters:
        module - the module to refresh
        Throws:
        java.lang.SecurityException - if the module was not defined by this module loader, or if the module loader does not have the required permissions associated with it
      • setAndRefreshResourceLoaders

        protected void setAndRefreshResourceLoaders​(Module module,
                                                    java.util.Collection<ResourceLoaderSpec> loaders)
        Replaces the resources loaders for the specified module and refreshes the internal path list that is derived from the loaders. This is an advanced method that should be used carefully, since it alters a live module. Modules that import resources from the specified module will not automatically be updated to reflect the change. For this to occur relink(Module) must be called on all of them.
        Parameters:
        module - the module to update and refresh
        loaders - the new collection of loaders the module should use
        Throws:
        java.lang.SecurityException - if the module was not defined by this module loader, or if the module loader does not have the required permissions associated with it
      • relink

        protected void relink​(Module module)
                       throws ModuleLoadException
        Relinks the dependencies associated with the specified Module. This is an advanced method that is intended to be called on all modules that directly or indirectly import dependencies that are re-exported by a module that has recently been updated and relinked via setAndRelinkDependencies(Module, java.util.List).
        Parameters:
        module - the module to relink
        Throws:
        ModuleLoadException - if relinking failed
        java.lang.SecurityException - if the module was not defined by this module loader, or if the module loader does not have the required permissions associated with it
      • setAndRelinkDependencies

        protected void setAndRelinkDependencies​(Module module,
                                                java.util.List<DependencySpec> dependencies)
                                         throws ModuleLoadException
        Replaces the dependencies for the specified module and relinks against the new modules This is an advanced method that should be used carefully, since it alters a live module. Modules that import dependencies that are re-exported from the specified module will not automatically be updated to reflect the change. For this to occur relink(Module) must be called on all of them.
        Parameters:
        module - the module to update and relink
        dependencies - the new dependency list
        Throws:
        ModuleLoadException - if relinking failed
        java.lang.SecurityException - if the module was not defined by this module loader, or if the module loader does not have the required permissions associated with it
      • getDependencies

        protected DependencySpec[] getDependencies​(Module module)
        Get the current dependency list for a module which was defined by this module loader, without any access checks.
        Returns:
        the current dependency list for the module
        Throws:
        java.lang.SecurityException - if the module was not defined by this module loader