de.umr.jepc.util

Class MagicLoader<S>

java.lang.Object

de.umr.jepc.util.MagicLoader<S>

public class MagicLoader<S>
extends java.lang.Object

Extension of the idea in java.util.ServiceLoader. This service loader implementation checks for the given constructor arguments.

Author:

Marc Seidemann

Constructor Summary

Constructors

Constructor and Description
MagicLoader(java.lang.Class<S> implementedInterface, java.lang.String... optionalClasses) Creates a new magic loader for the given class.
MagicLoader(java.lang.ClassLoader decorated, java.lang.Class<S> implementedInterface, java.lang.String... optionalClasses) Creates a new magic loader for the given class

Method Summary

Modifier and Type	Method and Description
java.util.Collection<java.lang.Class<? extends S>>	getImplementations(java.lang.String targetPackage) Returns a list of all implementations for the given interface in the give package.
S	load(java.lang.String packageName, java.lang.Object... arguments) Loads an implementation for the given interface in the given package.

Methods inherited from class java.lang.Object

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

Constructor Detail

MagicLoader

public MagicLoader(java.lang.Class<S> implementedInterface,
                   java.lang.String... optionalClasses)

Creates a new magic loader for the given class. This is equal to a call for this(Thread.currentThread().getContextClassLoader(), implementedInterface, className);

Parameters:

implementedInterface - the implemented interface this loader should load

optionalClasses - optional classes to be loaded with this class loader

MagicLoader

public MagicLoader(java.lang.ClassLoader decorated,
                   java.lang.Class<S> implementedInterface,
                   java.lang.String... optionalClasses)

Creates a new magic loader for the given class

Parameters:

decorated - the default class loader

implementedInterface - the implemented interface this loader should load

Method Detail

load

public S load(java.lang.String packageName,
              java.lang.Object... arguments)
       throws java.lang.Exception

Loads an implementation for the given interface in the given package. If an implementation within the given package has a constructor which parameters fit to the given argument list, a new object of that implementation is returned.

Parameters:

packageName - the name of the package

arguments - the the constructor arguments for the desired class

Returns:

a fitting implementation or null, if there is no implementation in the given package

Throws:

java.lang.Exception

getImplementations

public java.util.Collection<java.lang.Class<? extends S>> getImplementations(java.lang.String targetPackage)

Returns a list of all implementations for the given interface in the give package.

Parameters:

targetPackage - the target package for the implementation (reduces the search space)

Returns:

a collection containing all available implementations