bsh.classpath
Class ClassManagerImpl

java.lang.Object
  |
  +--bsh.BshClassManager
        |
        +--bsh.classpath.ClassManagerImpl

public class ClassManagerImpl

extends BshClassManager

        Manage all classloading in BeanShell.
        Allows classpath extension and class file reloading.

        This class holds the implementation of the BshClassManager so that it
        can be separated from the core package.

        This class currently relies on 1.2 for BshClassLoader and weak references.
        Is there a workaround for weak refs?  If so we could make this work
        with 1.1 by supplying our own classloader code...

        See "http://www.beanshell.org/manual/classloading.html" for details
        on the bsh classloader architecture.

        Bsh has a multi-tiered class loading architecture.  No class loader is
        used unless/until the classpath is modified or a class is reloaded.

        Note: we may need some synchronization in here

        Note on jdk1.2 dependency:

        We are forced to use weak references here to accomodate all of the 
        fleeting namespace listeners.  (NameSpaces must be informed if the class 
        space changes so that they can un-cache names).  I had the interesting 
        thought that a way around this would be to implement BeanShell's own 
        garbage collector...  Then I came to my senses and said - screw it, 
        class re-loading will require 1.2.
        

Nested Class Summary

Nested classes inherited from class bsh.BshClassManager

BshClassManager.Listener

Field Summary

Fields inherited from class bsh.BshClassManager

absoluteClassCache, absoluteNonClasses, resolvedObjectMethods, resolvedStaticMethods

Constructor Summary

ClassManagerImpl()
Used by BshClassManager singleton constructor

Method Summary

void	addClassPath(java.net.URL path)
void	addListener(BshClassManager.Listener l)
java.lang.Class	classForName(java.lang.String name) Load the specified class by name, taking into account added classpath and reloaded classes, etc.
protected void	classLoaderChanged() Clear global class cache and notify namespaces to clear their class caches.
void	doSuperImport() Support for "import *;" Hide details in here as opposed to NameSpace.
void	dump(java.io.PrintWriter i)
java.lang.ClassLoader	getBaseLoader()
java.lang.String	getClassNameByUnqName(java.lang.String name) Return the name or null if none is found, Throw an ClassPathException containing detail if name is ambigous.
BshClassPath	getClassPath() Get the full blown classpath.
java.net.URL	getResource(java.lang.String path) Get a resource URL using the BeanShell classpath
java.io.InputStream	getResourceAsStream(java.lang.String path) Get a resource stream using the BeanShell classpath
protected boolean	hasSuperImport() A "super import" ("import *") operation has been performed.
java.lang.Class	plainClassForName(java.lang.String name) Delegate for bottom level implementation of Class.forName().
void	reloadAllClasses() Overlay the entire path with a new class loader.
void	reloadClasses(java.lang.String[] classNames) Reloading classes means creating a new classloader and using it whenever we are asked for classes in the appropriate space.
void	reloadPackage(java.lang.String pack) Reload all classes in the specified package: e.g.
void	removeListener(BshClassManager.Listener l)
void	reset() Clear all classloading behavior and class caches and reset to initial state.
void	setClassPath(java.net.URL[] cp) Set a new base classpath and create a new base classloader.

Methods inherited from class bsh.BshClassManager

cacheClassInfo, cacheResolvedMethod, classExists, clearCaches, cmUnavailable, createClassManager, getResolvedMethod, noClassDefFound, setClassLoader

Methods inherited from class java.lang.Object

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

Constructor Detail

ClassManagerImpl

public ClassManagerImpl()

Used by BshClassManager singleton constructor

Method Detail

classForName

public java.lang.Class classForName(java.lang.String name)

Description copied from class: BshClassManager

Load the specified class by name, taking into account added classpath and reloaded classes, etc.

Overrides:

classForName in class BshClassManager

Returns:

the class or null

plainClassForName

public java.lang.Class plainClassForName(java.lang.String name)
                                  throws java.lang.ClassNotFoundException

Delegate for bottom level implementation of Class.forName(). This is here solely to provide for Java version specific features. In this case - the Thread getContextClassLoader() which is required to get bsh to see user classpath when it's installed in a web application or in the jre/lib/ext directory.

Overrides:

plainClassForName in class BshClassManager

Returns:

the class

java.lang.ClassNotFoundException

See Also:

BshClassManager.plainClassForName()

getResource

public java.net.URL getResource(java.lang.String path)

Get a resource URL using the BeanShell classpath

Overrides:

getResource in class BshClassManager

Parameters:

path - should be an absolute path

getResourceAsStream

public java.io.InputStream getResourceAsStream(java.lang.String path)

Get a resource stream using the BeanShell classpath

Overrides:

getResourceAsStream in class BshClassManager

Parameters:

path - should be an absolute path

addClassPath

public void addClassPath(java.net.URL path)
                  throws java.io.IOException

Overrides:

addClassPath in class BshClassManager

java.io.IOException

reset

public void reset()

Clear all classloading behavior and class caches and reset to initial state.

Overrides:

reset in class BshClassManager

setClassPath

public void setClassPath(java.net.URL[] cp)

Set a new base classpath and create a new base classloader. This means all types change.

Overrides:

setClassPath in class BshClassManager

reloadAllClasses

public void reloadAllClasses()
                      throws ClassPathException

Overlay the entire path with a new class loader. Set the base path to the user path + base path. No point in including the boot class path (can't reload thos).

Overrides:

reloadAllClasses in class BshClassManager

ClassPathException

reloadClasses

public void reloadClasses(java.lang.String[] classNames)
                   throws ClassPathException

Reloading classes means creating a new classloader and using it whenever we are asked for classes in the appropriate space. For this we use a DiscreteFilesClassLoader

Overrides:

reloadClasses in class BshClassManager

ClassPathException

reloadPackage

public void reloadPackage(java.lang.String pack)
                   throws ClassPathException

Reload all classes in the specified package: e.g. "com.sun.tools" The special package name "" can be used to refer to unpackaged classes.

Overrides:

reloadPackage in class BshClassManager

ClassPathException

getClassPath

public BshClassPath getClassPath()
                          throws ClassPathException

Get the full blown classpath.

ClassPathException

doSuperImport

public void doSuperImport()
                   throws UtilEvalError

Support for "import *;" Hide details in here as opposed to NameSpace.

Overrides:

doSuperImport in class BshClassManager

UtilEvalError

hasSuperImport

protected boolean hasSuperImport()

Description copied from class: BshClassManager

A "super import" ("import *") operation has been performed.

Overrides:

hasSuperImport in class BshClassManager

getClassNameByUnqName

public java.lang.String getClassNameByUnqName(java.lang.String name)
                                       throws ClassPathException

Return the name or null if none is found, Throw an ClassPathException containing detail if name is ambigous.

Overrides:

getClassNameByUnqName in class BshClassManager

ClassPathException

addListener

public void addListener(BshClassManager.Listener l)

Overrides:

addListener in class BshClassManager

removeListener

public void removeListener(BshClassManager.Listener l)

Overrides:

removeListener in class BshClassManager

getBaseLoader

public java.lang.ClassLoader getBaseLoader()

classLoaderChanged

protected void classLoaderChanged()

Clear global class cache and notify namespaces to clear their class caches. The listener list is implemented with weak references so that we will not keep every namespace in existence forever.

Overrides:

classLoaderChanged in class BshClassManager

dump

public void dump(java.io.PrintWriter i)

Overrides:

dump in class BshClassManager