All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class com.sun.jaw.impl.agent.services.mlet.MLetClassLoader

java.lang.Object
   |
   +----java.lang.ClassLoader
           |
           +----com.sun.jaw.impl.agent.services.mlet.MLetClassLoader

public class MLetClassLoader

extends ClassLoader

implements LibraryLoaderIf, Externalizable

This class loader can load classes and resources from:

• The system - from the location defined by the CLASSPATH environment variable
• .jar files

Note - Do not instantiate this class explicitly. The m-let service instantiates this class each time a load URL method is invoked.

When it instantiates this class, the m-let service registers the instance with the repository. This enables a client application to instantiate an m-bean loaded through this class loader by specifying its object name.

The class loader created is registered with an object name of the form:

defaultDomain:JavaClass.codebase=baseURL

where:

• defaultDomain is the domain associated with the core management framework.
• JavaClass is the full Java class name, including the package prefix, of the class loader used to create the m-bean. This is defined as the Java variable ServiceName.MLETLOADER.
• baseURL specifies the location of the code of the m-bean. It is either the base URL of the text file specified in the call to one of the load URL methods of the m-let service, or is the CODEBASE attribute specified in the MLET tag.

MLetClassLoader()

Instantiates the m-let class loader.

MLetClassLoader(URL)

Instantiates the m-let class loader with a specified codebase.

deleteCmf()

Deletes the m-let class loader.

getClassVersion()

Gets the version of this class.

getCodeBase()

Gets the code base of this instance of MLetClassLoader.

getLoaderName()

Gets the object name of this instance of MLetClassLoader.

getResource(String)

Gets the URL of a desired resource.

getResourceAsStream(String)

Gets an input stream for the desired resource.

getURLConnectionResource(String, String)

Gets the local resource object through the MLetURLConnection.

getURLConnectionResourceAsStream(String, String)

Gets the local resource object as an input stream through the MLetURLConnection.

initCmf(Framework, ObjectName, boolean, ModificationList)

Initializes the m-let class loader.

loadClass(String)

Loads a class from this class loader.

loadLibrary(String, String)

Loads a dynamic native library.

loadSerializedObject(URL, String)

Loads the serialized object specified by the OBJECT attribute of the MLET tag.

readExternal(ObjectInput)

This method reads the objects contents during Object Serialization.

setClassDefinition(String, byte[], int, int)

Sets some bytecodes as a definition for a class.

setResourceDefinition(String, byte[], String)

Sets some bytes as a definition of a resource.

writeExternal(ObjectOutput)

This method saves the objects contents during Object Serialization.

 public MLetClassLoader()

Instantiates the m-let class loader.

 public MLetClassLoader(URL codebase)

Instantiates the m-let class loader with a specified codebase.

 public void initCmf(Framework cmf,
                     ObjectName name,
                     boolean db,
                     ModificationList list) throws IllegalAccessException, InstanceAlreadyExistException

Initializes the m-let class loader. The method registers the m-let class loader with the core management framework.
For internal use only.

Parameters:

cmf - The core management framework to register the service with.

name - Object name containing configuration information.

db - Indicates if persistent storage is required.

list - The modification list to use for setting up parameters.

Throws: IllegalAccessException

The method cannot access the class definition of the m-let class loader.

Throws: InstanceAlreadyExistException

The m-let class loader is already registered.

 public void deleteCmf()

Deletes the m-let class loader.

 public MLetClassEntry setClassDefinition(String name,
                                          byte classbuf[],
                                          int start,
                                          int len)

Sets some bytecodes as a definition for a class. The class is not actually defined until later.

 public Class loadClass(String name) throws ClassNotFoundException

Loads a class from this class loader.

Throws: ClassNotFoundException

The specified class could not be found.

Overrides:

loadClass in class ClassLoader

 public Object loadSerializedObject(URL codebase,
                                    String filename) throws IOException, ClassNotFoundException

Loads the serialized object specified by the OBJECT attribute of the MLET tag.

Throws: ClassNotFoundException

The specified serialized object could not be found.

Throws: IOException

An I/O error occurred while loading serialized object.

 public void setResourceDefinition(String name,
                                   byte data[],
                                   String type)

Sets some bytes as a definition of a resource.

 public URL getResource(String name)

Gets the URL of a desired resource.

Returns:

The URL of the resource.

Overrides:

getResource in class ClassLoader

 public InputStream getResourceAsStream(String name)

Gets an input stream for the desired resource.

Returns:

an input stream for the desired resource.

Overrides:

getResourceAsStream in class ClassLoader

 public static synchronized Object getURLConnectionResource(String base,
                                                            String name) throws IOException

Gets the local resource object through the MLetURLConnection.

Returns:

The local resource object.

Throws: IOException

Signals that an I/O exception of some sort has occurred.

 public static synchronized InputStream getURLConnectionResourceAsStream(String base,
                                                                         String name) throws IOException

Gets the local resource object as an input stream through the MLetURLConnection.

Returns:

An inputs stream representing the required resource.

Throws: IOException

Signals that an I/O exception of some sort has occurred.

 public void loadLibrary(String baseName,
                         String libName) throws SecurityException, UnsatisfiedLinkError

Loads a dynamic native library.

Parameters:

basename - The basename argument is the unique library base name where the library is stored on the management server (jar file).

libname - The libname argument is either the full pathname of the library below the library base path or is a simple, architecture-independent library name where the path, prefix, and suffix for the library name are generated based on the appliance type on which the loadLibrary() call was made.

Throws: SecurityException

If the current thread cannot load the specified dynamic library.

Throws: UnsatisfiedLinkError

If the library does not exist.

 public void writeExternal(ObjectOutput out) throws IOException

This method saves the objects contents during Object Serialization.

Parameters:

out - The serialization output stream.

Throws: IOException

Signals that an I/O exception of some sort has occurred.

 public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException

This method reads the objects contents during Object Serialization.

Parameters:

in - The serialization input stream.

Throws: IOException

Signals that an I/O exception of some sort has occurred.

Throws: ClassNotFoundException

The class for an object being restored cannot be found.

 public static String getClassVersion()

Gets the version of this class.

Returns:

the version of this class.

 public URL getCodeBase()

Gets the code base of this instance of MLetClassLoader.

Returns:

The code base of this instance of MLetClassLoader.

 public ObjectName getLoaderName()

Gets the object name of this instance of MLetClassLoader.

Returns:

The object name of this instance of MLetClassLoader.

All Packages  Class Hierarchy  This Package  Previous  Next  Index