bsh
Class BshClassManager
public
class
BshClassManager
extends Object
BshClassManager manages all classloading in BeanShell.
It also supports a dynamically loaded extension (bsh.classpath package)
which allows classpath extension and class file reloading.
Currently the extension relies on 1.2 for BshClassLoader and weak
references.
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.
Method Summary |
void | addClassPath(URL path) |
void | addListener(BshClassManager.Listener l) |
void | cacheClassInfo(String name, Class value)
Cache info about whether name is a class or not. |
void | cacheResolvedMethod(Class clas, Object[] args, Method method)
Cache a resolved (possibly overloaded) method based on the
argument types used to invoke it, subject to classloader change.
|
boolean | classExists(String name) |
Class | classForName(String name)
Load the specified class by name, taking into account added classpath
and reloaded classes, etc. |
protected void | classLoaderChanged() |
protected void | clearCaches()
Clear the caches in BshClassManager |
protected static UtilEvalError | cmUnavailable() |
static BshClassManager | createClassManager()
Create a new instance of the class manager.
|
protected void | doSuperImport()
Support for "import *;"
Hide details in here as opposed to NameSpace. |
void | dump(PrintWriter pw) |
protected String | getClassNameByUnqName(String name)
Return the name or null if none is found,
Throw an ClassPathException containing detail if name is ambigous. |
Method | getResolvedMethod(Class clas, String methodName, Object[] args, boolean onlyStatic)
Return a previously cached resolved method. |
URL | getResource(String path)
Get a resource URL using the BeanShell classpath |
InputStream | getResourceAsStream(String path)
Get a resource stream using the BeanShell classpath |
protected boolean | hasSuperImport()
A "super import" ("import *") operation has been performed. |
protected static Error | noClassDefFound(String className, Error e)
Annotate the NoClassDefFoundError with some info about the class
we were trying to load. |
Class | plainClassForName(String name)
Perform a plain Class.forName() or call the externally provided
classloader.
|
void | reloadAllClasses()
Overlay the entire path with a new class loader.
|
void | reloadClasses(String[] classNames)
Reloading classes means creating a new classloader and using it
whenever we are asked for classes in the appropriate space.
|
void | reloadPackage(String pack)
Reload all classes in the specified package: e.g. |
void | removeListener(BshClassManager.Listener l) |
void | reset()
Clear all loaders and start over. |
void | setClassLoader(ClassLoader externalCL)
Set an external class loader. |
void | setClassPath(URL[] cp)
Set a new base classpath and create a new base classloader.
|
protected transient Hashtable absoluteClassCache
Global cache for things we know are classes.
Note: these should probably be re-implemented with Soft references.
(as opposed to strong or Weak)
protected transient Hashtable absoluteNonClasses
Global cache for things we know are *not* classes.
Note: these should probably be re-implemented with Soft references.
(as opposed to strong or Weak)
protected transient Hashtable resolvedObjectMethods
Caches for resolved object and static methods.
We keep these maps separate to support fast lookup in the general case
where the method may be either.
protected transient Hashtable resolvedStaticMethods
public void addClassPath(URL path)
public void cacheClassInfo(String name, Class value)
Cache info about whether name is a class or not.
Parameters: value
if value is non-null, cache the class
if value is null, set the flag that it is *not* a class to
speed later resolution
public void cacheResolvedMethod(Class clas, Object[] args, Method method)
Cache a resolved (possibly overloaded) method based on the
argument types used to invoke it, subject to classloader change.
Static and Object methods are cached separately to support fast lookup
in the general case where either will do.
public boolean classExists(String name)
public Class classForName(String name)
Load the specified class by name, taking into account added classpath
and reloaded classes, etc.
Returns: the class or null
protected void classLoaderChanged()
protected void clearCaches()
Clear the caches in BshClassManager
See Also: public void #reset() for external usage
Create a new instance of the class manager.
Class manager instnaces are now associated with the interpreter.
See Also: bsh.Interpreter.getClassManager()
bsh.Interpreter.setClassLoader( ClassLoader )
protected void doSuperImport()
Support for "import *;"
Hide details in here as opposed to NameSpace.
public void dump(PrintWriter pw)
protected String getClassNameByUnqName(String name)
Return the name or null if none is found,
Throw an ClassPathException containing detail if name is ambigous.
public Method getResolvedMethod(Class clas, String methodName, Object[] args, boolean onlyStatic)
Return a previously cached resolved method.
Parameters: onlyStatic specifies that only a static method may be returned.
Returns: the Method or null
public URL getResource(String path)
Get a resource URL using the BeanShell classpath
Parameters: path should be an absolute path
public InputStream getResourceAsStream(String path)
Get a resource stream using the BeanShell classpath
Parameters: path should be an absolute path
protected boolean hasSuperImport()
A "super import" ("import *") operation has been performed.
protected static Error noClassDefFound(String className, Error e)
Annotate the NoClassDefFoundError with some info about the class
we were trying to load.
public Class plainClassForName(String name)
Perform a plain Class.forName() or call the externally provided
classloader.
If a BshClassManager implementation is loaded the call will be
delegated to it, to allow for additional hooks.
This simply wraps that bottom level class lookup call and provides a
central point for monitoring and handling certain Java version
dependent bugs, etc.
Returns: the class
See Also: BshClassManager
public void reloadAllClasses()
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).
public void reloadClasses(String[] classNames)
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
public void reloadPackage(String pack)
Reload all classes in the specified package: e.g. "com.sun.tools"
The special package name "" can be used to refer
to unpackaged classes.
public void reset()
Clear all loaders and start over. No class loading.
public void setClassLoader(ClassLoader externalCL)
Set an external class loader. BeanShell will use this at the same
point it would otherwise use the plain Class.forName().
i.e. if no explicit classpath management is done from the script
(addClassPath(), setClassPath(), reloadClasses()) then BeanShell will
only use the supplied classloader. If additional classpath management
is done then BeanShell will perform that in addition to the supplied
external classloader.
However BeanShell is not currently able to reload
classes supplied through the external classloader.
public void setClassPath(URL[] cp)
Set a new base classpath and create a new base classloader.
This means all types change.
B) 2000 pat@pat.net :-)