org.brains2b.loader

Class DynamicClassLoader

java.lang.Object

org.brains2b.loader.DynamicClassLoader

public final class DynamicClassLoader
extends java.lang.Object

Loads classes dynamically from a directory or jar/zip file being passed in. It is not a class loader itself, but uses URLClassLoader to do the actual loading. It does supply the following options:

• find an Implementation of a Class or Interface in the classpath supplied and load them, f.e. java.sql.Driver in a specific vendors driver jar
• Load a specific class from a jar
• Load all classes from a jar

Note:If you load individual classes the classes referring to that class are also automatically loaded as long as they are available in the classpath supplied or in the bootstrap of the JVM.

Version:

1.00 [12-02-2006]

Author:

dennis@brains2b.nl

Method Summary

Modifier and Type	Method and Description
static java.lang.Class[]	findImplementation(java.lang.Class superOrInterface, java.net.URL[] url) find an implementation of an interface or class in the classpath supplied by the URLs
static java.lang.Class	loadClass(java.lang.String name, java.net.URL[] url) load a specific class identified by it's fully qualified name from the passed URLs
static java.lang.Class[]	loadClasses(java.net.URL[] url) load all the classes from the classpath supplied by the URLs

Methods inherited from class java.lang.Object

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

Method Detail

loadClass

public static final java.lang.Class loadClass(java.lang.String name,
                                              java.net.URL[] url)
                                       throws java.lang.ClassNotFoundException

load a specific class identified by it's fully qualified name from the passed URLs

Parameters:

name - String, the fully qualified class name

url - URL[], an array of URLs in which to find the class

Returns:

Class, the loaded Class. If url is null an attempt is made to load the class from the current ClassLoader

Throws:

java.lang.ClassNotFoundException - thrown if the class being loaded cannot be found in the supplied classpath or current ClassLoader if url was null.

loadClasses

public static final java.lang.Class[] loadClasses(java.net.URL[] url)
                                           throws java.lang.ClassNotFoundException

load all the classes from the classpath supplied by the URLs

Parameters:

url - URL[], the paths to the classes or the jar file

Returns:

Class[] all the classes that have been loaded from the given URLs

Throws:

java.lang.ClassNotFoundException - thrown if a class cannot be loaded from one of the locations supplied by the URLs.

findImplementation

public static final java.lang.Class[] findImplementation(java.lang.Class superOrInterface,
                                                         java.net.URL[] url)
                                                  throws java.lang.ClassNotFoundException

find an implementation of an interface or class in the classpath supplied by the URLs

Parameters:

superOrInterface - Class, the super class or interface to find in the classpath

url - URL[], the paths to the classes or the jar file

Returns:

Class[] the classes that implement the class or interface or null if it cannot be found.

Throws:

java.lang.ClassNotFoundException - thrown if a class cannot be loaded from one of the locations supplied by the URLs.