org.rvpf.service

Class ServiceClassLoader

Object

ClassLoader

ServiceClassLoader

All Implemented Interfaces:

Alert.Dispatcher, ClassDef.Loader

public final class ServiceClassLoader
extends ClassLoader
implements ClassDef.Loader, Alert.Dispatcher

Service class loader.

Adds class libraries support. Their configuration may specify that they should be copied in a local cache for greater availability.

This implementation uses two levels of class loaders by inserting a slightly modified URLClassLoader between this and the original parent.

Field Summary

Fields

Modifier and Type	Field and Description
static String	CACHE_SECTION_NAME Cache section name for jars.
static String	CLASSLIB_DIR_PROPERTY Contains the path to the ClassLib jars directory.
static String	CLASSLIB_SERVER_PROPERTY The URL to the ClassLib server.

Method Summary

Modifier and Type	Method and Description
void	activate() Activates this.
void	addFromClassLib(ClassLibEntity classLib) Adds URLs from a class library to the class path.
void	addFromClassLibs(List<ClassLibEntity> classLibs) Adds URLs from class libraries to the class path.
void	addFromLocation(String location) Adds URLs from a location to the class path.
void	addFromLocation(URI location) Adds URLs from a location to the class path.
void	dispatchAlert(Logger.LogLevel alertLevel, String alertName, String info) Dispatches an alert.
void	forgetConfig(Config config) Forgets the current config object if it is the one assumed as current.
Optional<Config>	getConfig() Gets the configuration context.
static ServiceClassLoader	getInstance() Gets a service class loader.
static ServiceClassLoader	getInstance(ClassLoader parent) Gets a service class loader.
URL[]	getURLs() Gets the search path of URLs for loading classes and resources.
static Optional<ServiceClassLoader>	hideInstance() Hides the current service class loader instance.
boolean	isLoaded(String className) Asks if a class has been loaded.
static void	restoreInstance(Optional<ServiceClassLoader> serviceClassLoader) Restores a service class loader instance.
void	useConfig(Config config) Sets the context to use for getting properties.

Methods inherited from class ClassLoader

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

Methods inherited from class Object

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

Field Detail

CACHE_SECTION_NAME

public static final String CACHE_SECTION_NAME

Cache section name for jars.

See Also:

Constant Field Values

CLASSLIB_DIR_PROPERTY

public static final String CLASSLIB_DIR_PROPERTY

Contains the path to the ClassLib jars directory.

See Also:

Constant Field Values

CLASSLIB_SERVER_PROPERTY

public static final String CLASSLIB_SERVER_PROPERTY

The URL to the ClassLib server.

See Also:

Constant Field Values

Method Detail

getInstance

@Nonnull
 @CheckReturnValue
public static ServiceClassLoader getInstance()

Gets a service class loader.

If the current thread context class loader is already a service class loader, it will be returned; otherwise a new instance is returned.

Returns:

The service class loader.

getInstance

@Nonnull
 @CheckReturnValue
public static ServiceClassLoader getInstance(@Nonnull
                                                                           ClassLoader parent)

Gets a service class loader.

If the supplied parent is already a service class loader, it will be returned; otherwise a new instance is returned.

Parameters:

parent - The parent class loader.

Returns:

The service class loader.

hideInstance

@Nonnull
 @CheckReturnValue
public static Optional<ServiceClassLoader> hideInstance()

Hides the current service class loader instance.

Returns:

The optional service class loader instance.

restoreInstance

public static void restoreInstance(@Nonnull
                                   Optional<ServiceClassLoader> serviceClassLoader)

Restores a service class loader instance.

Parameters:

serviceClassLoader - The optional service class loader instance.

activate

public void activate()

Activates this.

addFromClassLib

public void addFromClassLib(@Nonnull
                            ClassLibEntity classLib)
                     throws UndefinedEntityException

Adds URLs from a class library to the class path.

Redundant additions of the same class library are ignored. Also, multiple references to the same URL are filtered.

Parameters:

classLib - The class library holding the URLs.

Throws:

UndefinedEntityException - When the interface is undefined.

addFromClassLibs

public void addFromClassLibs(@Nonnull
                             List<ClassLibEntity> classLibs)
                      throws UndefinedEntityException

Adds URLs from class libraries to the class path.

Redundant additions of the same class library are ignored. Also, multiple references to the same URL are filtered.

Parameters:

classLibs - The class libraries holding the URLs.

Throws:

UndefinedEntityException - When the interface is undefined.

addFromLocation

public void addFromLocation(@Nonnull
                            String location)

Adds URLs from a location to the class path.

Multiple references to the same URL are filtered.

Parameters:

location - The location.

addFromLocation

public void addFromLocation(@Nonnull
                            URI location)

Adds URLs from a location to the class path.

Multiple references to the same URL are filtered.

Parameters:

location - The location.

dispatchAlert

public void dispatchAlert(Logger.LogLevel alertLevel,
                          String alertName,
                          String info)

Dispatches an alert.

Specified by:

dispatchAlert in interface Alert.Dispatcher

Parameters:

alertLevel - The alert level.

alertName - The alert name.

info - The alert info.

forgetConfig

public void forgetConfig(@Nonnull
                         Config config)

Forgets the current config object if it is the one assumed as current.

Parameters:

config - The config object assumed as current.

getConfig

@Nonnull
 @CheckReturnValue
public Optional<Config> getConfig()

Gets the configuration context.

Returns:

The optional configuration context.

getURLs

@Nonnull
 @CheckReturnValue
public URL[] getURLs()

Gets the search path of URLs for loading classes and resources.

Returns:

The search path of URLs for loading classes and resources.

isLoaded

public boolean isLoaded(String className)

Asks if a class has been loaded.

Specified by:

isLoaded in interface ClassDef.Loader

Parameters:

className - The class name.

Returns:

True if the class has been loaded.

useConfig

public void useConfig(@Nonnull
                      Config config)

Sets the context to use for getting properties.

Parameters:

config - The config object.