Package edu.rit.pj.cluster

Class BackendClassLoader

java.lang.Object

java.lang.ClassLoader

edu.rit.pj.cluster.BackendClassLoader

public class BackendClassLoader
extends ClassLoader

Class BackendClassLoader provides a class loader for a job backend process in the PJ cluster middleware. If a backend class loader is requested to load a class and the parent class loaders cannot do so, the backend class loader sends a request for the class file to the job frontend process, waits for the job frontend process to send the class file, and loads the class.

Version:

15-Jun-2012

Author:

Alan Kaminsky

Constructor Summary

Constructors

Constructor	Description
BackendClassLoader(JobBackendRef theJobBackend, JobFrontendRef theJobFrontend, ResourceCache theCache)	Construct a new backend class loader.
BackendClassLoader(ClassLoader parent, JobBackendRef theJobBackend, JobFrontendRef theJobFrontend, ResourceCache theCache)	Construct a new backend class loader.

Method Summary

Modifier and Type	Method	Description
protected Class<?>	findClass(String className)	Find the class with the given name.
protected URL	findResource(String name)	Find the resource with the given name.

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findClass, findLibrary, findLoadedClass, findResource, findResources, findSystemClass, getClassLoadingLock, getDefinedPackage, getDefinedPackages, getName, getPackage, getPackages, getParent, getPlatformClassLoader, getResource, getResourceAsStream, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, getUnnamedModule, isRegisteredAsParallelCapable, loadClass, loadClass, registerAsParallelCapable, resolveClass, resources, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

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

Constructor Details

BackendClassLoader

public BackendClassLoader(JobBackendRef theJobBackend,
 JobFrontendRef theJobFrontend,
 ResourceCache theCache)

Construct a new backend class loader. The parent class loader is the one returned by ClassLoader.getSystemClassLoader(). Class files will be requested from theJobFrontend. Class files will be stored in theCache.

Parameters:

theJobBackend - Reference to job backend.

theJobFrontend - Reference to job frontend.

theCache - Resource cache.

BackendClassLoader

public BackendClassLoader(ClassLoader parent,
 JobBackendRef theJobBackend,
 JobFrontendRef theJobFrontend,
 ResourceCache theCache)

Construct a new backend class loader. The parent class loader is parent. Class files will be requested from theJobFrontend. Class files will be stored in theCache.

Parameters:

parent - Parent class loader.

theJobBackend - Reference to job backend.

theJobFrontend - Reference to job frontend.

theCache - Resource cache.

Method Details

findClass

protected Class<?> findClass(String className)
                      throws ClassNotFoundException

Find the class with the given name.

Overrides:

findClass in class ClassLoader

Throws:

ClassNotFoundException - Thrown if the class could not be found.

findResource

protected URL findResource(String name)

Find the resource with the given name.

Overrides:

findResource in class ClassLoader