Package eu.bandm.tools.util

Class ConfigurableClassLoader

java.lang.Object

java.lang.ClassLoader

eu.bandm.tools.util.ConfigurableClassLoader

public class ConfigurableClassLoader
extends ClassLoader

A class loader that mimics the -classpath behavior of java. It supports loading from local directories and jar files, also honoring Class-Path manifest entries.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	ConfigurableClassLoader.ClassDirectory	Directory in the file system from which a class can be loaded.
class	ConfigurableClassLoader.ClassSource	Abstract location from which a class can be loaded.
class	ConfigurableClassLoader.JarArchive	A jar archive from which a class can be loaded.

Field Summary

Fields

Modifier and Type	Field	Description
protected final Map<String,Class<?>>	local	Directory of all classes which already have been delivered by this class loader.
protected final List<ConfigurableClassLoader.ClassSource>	sources	Internal list of all sources.

Constructor Summary

Constructors

Constructor	Description
ConfigurableClassLoader()	Default constructor.
ConfigurableClassLoader(String... classpath)	Constructor which sets up the sources for class loading according to its string atguments.

Method Summary

Modifier and Type	Method	Description
void	addSource(String classpath)	Add one or more sources.
void	addSource(String... classpath)	Executes addSource(String) for all arguments.
protected Class<?>	findClass(String name)	Central point of service: return the loaded class object for the class with the given name.
byte[]	getClassData(String name)	Central point of service: return all class data for the class with the given name.
final Map<String,Class<?>>	getLocalClasses()	Get an unmodifiable copy of the directory of all classes which already have been delivered by this class loader.
protected Class<?>	loadClass(String name, boolean resolve)
Collection<ConfigurableClassLoader.ClassSource>	sources()	Returns all currently known sources to search for class files.
protected void	watchClass(String name, byte[] data)	Callback-hook to be overwritten by a user for diagnosis.

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findClass, findLibrary, findLoadedClass, findResource, findResource, findResources, findSystemClass, getClassLoadingLock, getDefinedPackage, getDefinedPackages, getName, getPackage, getPackages, getParent, getPlatformClassLoader, getResource, getResourceAsStream, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, getUnnamedModule, isRegisteredAsParallelCapable, 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

Field Details

sources

protected final List<ConfigurableClassLoader.ClassSource> sources

Internal list of all sources. These will be searched in sequential order for the first found class.

local

protected final Map<String,Class<?>> local

Directory of all classes which already have been delivered by this class loader.

Constructor Details

ConfigurableClassLoader

public ConfigurableClassLoader()

Default constructor. Its result has no source from which to load a class. At least one must be added by calling addSource(String) or addSource(String[]) explicitly.

ConfigurableClassLoader

public ConfigurableClassLoader(String... classpath)

Constructor which sets up the sources for class loading according to its string atguments. These are parsed as described with addSource(String).

Parameters:

classpath - array of strings, each standing for places to load classes from.

Method Details

watchClass

protected void watchClass(String name,
 byte[] data)

Callback-hook to be overwritten by a user for diagnosis. Is called whenever a class is successfully loaded by findClass(String).

addSource

public void addSource(String... classpath)

Executes addSource(String) for all arguments.

Parameters:

classpath - list of strings, see addSource(String).

addSource

public void addSource(String classpath)

Add one or more sources. The string can have the format of a Java "-classpath" argument and will be split by File.pathSeparatorChar. Otherwise it stands for one directory from which to load classes. If it stands for a single (non-directory) file, this must be a ".jar" file.

Parameters:

classpath - either a single source (directory or jar file) or multiples joined by File.pathSeparatorChar

sources

public Collection<ConfigurableClassLoader.ClassSource> sources()

Returns all currently known sources to search for class files.

getLocalClasses

public final Map<String,Class<?>> getLocalClasses()

Get an unmodifiable copy of the directory of all classes which already have been delivered by this class loader.

loadClass

protected Class<?> loadClass(String name,
 boolean resolve)
                      throws ClassNotFoundException

Overrides:

loadClass in class ClassLoader

Throws:

ClassNotFoundException

findClass

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

Central point of service: return the loaded class object for the class with the given name. All sources contained in sources are searched in sequential order for the first hit, by calling their findClass(name) method is called.

Overrides:

findClass in class ClassLoader

Parameters:

name - the "binary name" of the class to look for, see the discussion with ClassLoader

Returns:

the class object

Throws:

ClassNotFoundException - if no class with the given name is found in any source.

getClassData

public byte[] getClassData(String name)
                    throws ClassNotFoundException

Central point of service: return all class data for the class with the given name. All sources contained in sources are searched in sequential order for the first hit.

Parameters:

name - of the class to look for

Returns:

the byte array containing the complete byte code of the class.

Throws:

ClassNotFoundException - if no class with the given name is found in any source.