Package org.glassfish.internal.api

Interface ClassLoaderHierarchy

@Contract public interface ClassLoaderHierarchy
This class is responsible for creation of class loader hierarchy of an application.
Author:
Sanjeeb.Sahoo@Sun.COM

  • Method Details

    • getAPIClassLoader

      ClassLoader getAPIClassLoader()
      Returns a ClassLoader that can load classes exported by any OSGi bundle in the system for public use. Such classes include Jakarta EE API, AMX API, appserv-ext API, etc. CommonClassLoader delegates to this class loader.
      Returns:
      a ClassLoader that can load classes exported by any bundles

    • getCommonClassLoader

      ClassLoader getCommonClassLoader()
      Returns a class loader that is common to all deployed applications. Common Class Loader is responsible for loading classes from following URLs (the order is strictly maintained): lib/*.jar:domain_dir/lib/classes:domain_dir/lib/*.jar. Please note that domain_dir/lib/classes comes before domain_dir/lib/*.jar, just like WEB-INF/classes is searched first before WEB-INF/lib/*.jar. It delegates to APIClassLoader.
      Returns:
      ClassLoader common to all deployed applications.
      See Also:

    • getCommonClassPath

      String getCommonClassPath()
      Returns the classpath equiavalent to what is used by classloader returned by getCommonClassLoader(). Classpath entries are separated by File.separatorChar, but don't assume there will be any leading or trailing separator char. It returns an empty string if there are no libraries installed.
      Returns:
      ClassPath separated by File.pathSeparatorChar

    • getConnectorClassLoader

      DelegatingClassLoader getConnectorClassLoader(String application)
      Returns the class loader which has visibility to appropriate list of standalone RARs deployed in the server. Depending on a policy, this can either return a singleton classloader for all applications or a class loader specific to an application. When a singleton class loader is returned, such a class loader will have visibility to all the standalone RARs deployed in the system. When a class loader specific to an application is returned, such a class loader will have visibility to only standalone RARs that the application depends on.
      Parameters:
      application - Application whose class loader hierarchy is being set
      Returns:
      class loader which has visibility to appropriate list of standalone RARs.

    • getAppLibClassLoader

      ClassLoader getAppLibClassLoader(String application, List<URI> libURIs) throws MalformedURLException
      Returns AppLibClassLoader. As the name suggests, this class loader has visibility to deploy time libraries (--libraries and EXTENSION_LIST of MANIFEST.MF, provided the library is available in 'applibs' directory) for an application. It is different from CommonClassLoader in a sense that the libraries that are part of common class loader are shared by all applications, where as this class loader adds a scope to a library.
      Parameters:
      application - Application for which this class loader is created
      libURIs - list of URIs, where each URI represent a library
      Returns:
      class loader that has visibility to appropriate application specific libraries.
      Throws:
      MalformedURLException
      See Also:

    • getAppLibClassFinder

      DelegatingClassLoader.ClassFinder getAppLibClassFinder(List<URI> libURIs) throws MalformedURLException
      Returns ApplibClassFinder. As the name suggests, this class finder has visibility to deploy time libraries (--libraries and EXTENSION_LIST of MANIFEST.MF, provided the library is available in 'applibs' directory) for an application. It is different from CommonClassLoader in a sense that the libraries that are part of common class loader are shared by all applications, where as this class loader adds a scope to a library.
      NOTE : Difference between this API and getAppLibClassLoader(String, List<URI>) is the latter will be used by all applications (for its parent classloader) whereas this API will be used only by connector classloader. All other application classloaders will have AppLibClassLoader as parent where as connector classloader will be above AppLibClassLoader and hence simple delegation is not feasible.
      Parameters:
      libURIs - list of URIs, where each URI represent a library
      Returns:
      class loader that has visibility to appropriate application specific libraries.
      Throws:
      MalformedURLException
      See Also:

    • createApplicationParentCL

      ClassLoader createApplicationParentCL(ClassLoader parent, org.glassfish.api.deployment.DeploymentContext context) throws com.sun.enterprise.module.ResolveError
      Sets up the parent class loader for the application class loader. Application class loader are under the control of the ArchiveHandler since a special archive file format will require a specific class loader. However GlassFish needs to be able to add capabilities to the application like adding APIs accessibility, this is done through its parent class loader which we create and maintain.
      Parameters:
      parent - the parent class loader
      context - deployment context
      Returns:
      class loader capable of loading public APIs identified by the deployers
      Throws:
      com.sun.enterprise.module.ResolveError - if one of the deployer's public API module is not found.