Module System API
Official

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Description

Module System API

org.openide.modules

NetBeans is capable of being extended by pluggable modules providing additional functionality.

What is New (see all changes)?

• Feb 23 '08 Ability to hide JRE packages from the module classpath

  Packages supplied in a module which overlap those in the JRE or its extensions will normally be ignored (as usual, the JRE takes precedence). Modules which wish to specifically suppress loading of some packages from the classpath can now request the class loader to do so by specifying:

  OpenIDE-Module-Hide-Classpath-Packages: javax.lang.model.*, com.sun.source.**

  (The syntax is analogous to that of OpenIDE-Module-Public-Packages.)

  Such a declaration affects not just this module, but any other modules declaring a direct dependency on it (OpenIDE-Module-Module-Dependencies). The module is now free to bundle its own versions of these classes and be sure they will be used by it and its clients. Be aware that as with all changes to the normal class loading scheme, careless usage could result in LinkageErrors.

• Feb 15 '08 No longer possible to obtain a module JAR entry as a FileObject

  Modules used to be able to obtain their own entries as file objects, e.g.:

  FileObject f = URLMapper.findFileObject(ThisClass.class.getResource("something.xml"));

  This is no longer supported. Client code should either use module classpath entries directly as URLs; or register files of interest in the XML layer and refer to them using the system filesystem.

• Jul 18 '07 Enhanced support for OS specific modules (part II)

  Modules can now express dependencies on org.openide.modules.os.Linux and org.openide.modules.os.Solaris. For more details read here.

• Aug 1 '06 An option to revert user's modifications to XML layer files

  FileObjects created on XML layer now support a new attribute "removeWritables" returning an instance of Callable which removes the local writable version of the given FileObject thus reverting the folder or file to its initial state as defined in XML layers. Please note that is *not* possible to reset FileObject's attributes.

• Jul 19 '06 Requires/Provides and Needs

  It is possible to require some implementation using OpenIDE-Module-Needs: token which is slightly less restrictive than usual OpenIDE-Module-Requires: token as explain in the documentation.

Use Cases

How a classpath of my module is constructed?

The NetBeans is defacto a container that manages individual module's lifecycle and other runtime aspects. One of the important things is that it creates a runtime classpath for provided modules based on dependencies they specify in their manifests. The overview of the runtime infrastructure is a good starting place for everyone who wishes to learn more about the NetBeans runtime container behaviour.

Exported Interfaces

This table lists all of the module exported APIs with defined stability classifications. It is generated based on answers to questions about the architecture of the module. Read them all...

Group of java interfaces

Interface Name	In/Out	Stability	Specified in What Document?
ModulesAPI	Exported	Official	.../org/openide/modules/doc-files/api.html
CoreModulesAPI	Exported	Friend

Group of property interfaces

Interface Name	In/Out	Stability	Specified in What Document?
RevertFSModifications	Exported	Under Development	FileObjects created on XML layer now support a new attribute removeWritables returning an instance of Callable which removes the local writable version of the given FileObject thus reverting the folder or file to its initial state as defined in XML layers. Please note that is not possible to reset FileObject's attributes.
netbeans.systemclassloader.patches	Exported	Friend	Classpath appended to the system class loader. Used for automated testing infrastructure.
netbeans.cache.manifests	Exported	Private	By default true, may be turned off to disable manifest caching.
netbeans.patches.MODULE.CODE.NAME.BASE	Exported	Friend	Patch directories or JARs to add to the class loader for a module, besides patches/MODULE-CODE-NAME-BASE/*.jar.
netbeans.preresolve.classes	Exported	Private	If true, all module classes are forcibly loaded at startup, to help detect possible linkage errors.
org.netbeans.core.modules.NbInstaller.noAutoDeps	Exported	Private	Disables automatic module dependency upgrades.
org.netbeans.core.modules	Exported	Private	If set to 0, enables logging for the module system.
org.netbeans.core.modules.NbInstaller.NO_COMPAT_AUTO_TRANSITIVE_DEPS	Exported	Private	Disabled automatic transitive class loader dependencies for old modules.
netbeans.modules.quiet	Exported	Private	Avoids text messaging (other than ErrorManager logging) to the console from the module system.
netbeans.moduleitem.dontverifyclassloader	Exported	Private	Suppresses checks to ensure that module section classes are actually loaded from the module itself.
netbeans.security.nocheck	Exported	Friend	Suppress security checks in the VM, even from "untrusted" code.
netbeans.classloader.verbose	Exported	Private	Prints messages when resources or classes are loaded from JARs.
netbeans.cache.layers	Exported	Private	Used to control the XML layer cache mechanism. Value may be a fully-qualified class name to load as a manager (implement org.netbeans.core.projects.cache.LayerCacheManager), or - to disable caching and always parse the XML layers directly. Current default is to use a binary cache manager.

Group of dtd interfaces

Interface Name	In/Out	Stability	Specified in What Document?
module-status-1_0.dtd	Exported	Under Development	.../dtds/module-status-1_0.dtd -//NetBeans//DTD Module Status 1.0//EN
module-auto-deps-1_0.dtd	Exported	Under Development	.../dtds/module-auto-deps-1_0.dtd -//NetBeans//DTD Module Automatic Dependencies 1.0//EN
filesystem-1_1.dtd	Exported	Stable	.../www.netbeans.org/dtds/filesystem-1_1.dtd -//NetBeans//DTD Filesystem 1.1//EN

Implementation Details

Read more about the implementation in the answers to architecture questions.