Class BSFManager
- java.lang.Object
-
- org.apache.bsf.BSFManager
-
public class BSFManager extends java.lang.Object
This class is the entry point to the bean scripting framework. An application wishing to integrate scripting to a Java app would place an instance of a BSFManager in their code and use its services to register the beans they want to make available for scripting, load scripting engines, and run scripts.BSFManager serves as the registry of available scripting engines as well. Loading and unloading of scripting engines is supported as well. Each BSFManager loads one engine per language. Several BSFManagers can be created per JVM.
- Author:
- Sanjiva Weerawarana, Matthew J. Duftler, Sam Ruby, Olivier Gruber (added original debugging support), Don Schwarz (added support for registering languages dynamically)
-
-
Field Summary
Fields Modifier and Type Field Description protected java.lang.ClassLoader
classLoader
protected java.lang.String
classPath
protected java.util.Vector
declaredBeans
protected static java.util.Hashtable
extn2Lang
protected java.util.Hashtable
loadedEngines
protected ObjectRegistry
objectRegistry
protected java.beans.PropertyChangeSupport
pcs
protected static java.util.Hashtable
registeredEngines
protected java.lang.String
tempDir
protected static java.lang.String
version
-
Constructor Summary
Constructors Constructor Description BSFManager()
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description java.lang.Object
apply(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object funcBody, java.util.Vector paramNames, java.util.Vector arguments)
Apply the given anonymous function of the given language to the given parameters and return the resulting value.void
compileApply(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object funcBody, java.util.Vector paramNames, java.util.Vector arguments, CodeBuffer cb)
Compile the application of the given anonymous function of the given language to the given parameters into the given CodeBuffer.void
compileExpr(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object expr, CodeBuffer cb)
Compile the given expression of the given language into the given CodeBuffer.void
compileScript(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object script, CodeBuffer cb)
Compile the given script of the given language into the given CodeBuffer.void
declareBean(java.lang.String beanName, java.lang.Object bean, java.lang.Class type)
Declare a bean.java.lang.Object
eval(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object expr)
Evaluate the given expression of the given language and return the resulting value.void
exec(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object script)
Execute the given script of the given language.java.lang.ClassLoader
getClassLoader()
Get classLoaderjava.lang.String
getClassPath()
Get classPathstatic java.lang.String
getLangFromFilename(java.lang.String fileName)
Determine the language of a script file by looking at the file extension.ObjectRegistry
getObjectRegistry()
Return the current object registry of the manager.java.lang.String
getTempDir()
Get tempDirstatic java.lang.String
getVersion()
Returns the version string of BSF.void
iexec(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object script)
Execute the given script of the given language, attempting to emulate an interactive session w/ the language.static boolean
isLanguageRegistered(java.lang.String lang)
Determine whether a language is registered.BSFEngine
loadScriptingEngine(java.lang.String lang)
Load a scripting engine based on the lang string identifying it.java.lang.Object
lookupBean(java.lang.String beanName)
return a handle to a bean registered in the bean registry by the application or a scripting engine.void
registerBean(java.lang.String beanName, java.lang.Object bean)
Registering a bean allows a scripting engine or the application to access that bean by name and to manipulate it.static void
registerScriptingEngine(java.lang.String lang, java.lang.String engineClassName, java.lang.String[] extensions)
Register a scripting engine in the static registry of the BSFManager.void
setClassLoader(java.lang.ClassLoader classLoader)
Set the class loader for those that need to use it.void
setClassPath(java.lang.String classPath)
Set the classpath for those that need to use it.void
setObjectRegistry(ObjectRegistry objectRegistry)
Set the object registry used by this manager.void
setTempDir(java.lang.String tempDir)
Temporary directory to put stuff into (for those who need to).void
terminate()
Gracefully terminate all enginesvoid
undeclareBean(java.lang.String beanName)
Undeclare a previously declared bean.void
unregisterBean(java.lang.String beanName)
Unregister a previously registered bean.
-
-
-
Field Detail
-
version
protected static java.lang.String version
-
registeredEngines
protected static java.util.Hashtable registeredEngines
-
extn2Lang
protected static java.util.Hashtable extn2Lang
-
loadedEngines
protected java.util.Hashtable loadedEngines
-
objectRegistry
protected ObjectRegistry objectRegistry
-
pcs
protected java.beans.PropertyChangeSupport pcs
-
classLoader
protected java.lang.ClassLoader classLoader
-
tempDir
protected java.lang.String tempDir
-
classPath
protected java.lang.String classPath
-
declaredBeans
protected java.util.Vector declaredBeans
-
-
Method Detail
-
getVersion
public static java.lang.String getVersion()
Returns the version string of BSF.- Returns:
- version string in the form "abc.yyyymmdd" where
"abc" represents a dewey decimal number (three levels, each between 0 and 9), and
"yyyy" a four digit year, "mm" a two digit month,
"dd" a two digit day.
Example: "240.20061006
" stands for: BSF version2.4.0
as of2006-10-06
. - Since:
- 2006-01-17
-
apply
public java.lang.Object apply(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object funcBody, java.util.Vector paramNames, java.util.Vector arguments) throws BSFException
Apply the given anonymous function of the given language to the given parameters and return the resulting value.- Parameters:
lang
- language identifiersource
- (context info) the source of this expression (e.g., filename)lineNo
- (context info) the line number in source for exprcolumnNo
- (context info) the column number in source for exprfuncBody
- the multi-line, value returning script to evaluateparamNames
- the names of the parameters above assumesarguments
- values of the above parameters- Throws:
BSFException
- if anything goes wrong while running the script
-
compileApply
public void compileApply(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object funcBody, java.util.Vector paramNames, java.util.Vector arguments, CodeBuffer cb) throws BSFException
Compile the application of the given anonymous function of the given language to the given parameters into the given CodeBuffer.- Parameters:
lang
- language identifiersource
- (context info) the source of this expression (e.g., filename)lineNo
- (context info) the line number in source for exprcolumnNo
- (context info) the column number in source for exprfuncBody
- the multi-line, value returning script to evaluateparamNames
- the names of the parameters above assumesarguments
- values of the above parameterscb
- code buffer to compile into- Throws:
BSFException
- if anything goes wrong while running the script
-
compileExpr
public void compileExpr(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object expr, CodeBuffer cb) throws BSFException
Compile the given expression of the given language into the given CodeBuffer.- Parameters:
lang
- language identifiersource
- (context info) the source of this expression (e.g., filename)lineNo
- (context info) the line number in source for exprcolumnNo
- (context info) the column number in source for exprexpr
- the expression to compilecb
- code buffer to compile into- Throws:
BSFException
- if any error while compiling the expression
-
compileScript
public void compileScript(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object script, CodeBuffer cb) throws BSFException
Compile the given script of the given language into the given CodeBuffer.- Parameters:
lang
- language identifiersource
- (context info) the source of this script (e.g., filename)lineNo
- (context info) the line number in source for scriptcolumnNo
- (context info) the column number in source for scriptscript
- the script to compilecb
- code buffer to compile into- Throws:
BSFException
- if any error while compiling the script
-
declareBean
public void declareBean(java.lang.String beanName, java.lang.Object bean, java.lang.Class type) throws BSFException
Declare a bean. The difference between declaring and registering is that engines are spsed to make declared beans "pre-available" in the scripts as far as possible. That is, if a script author needs a registered bean, he needs to look it up in some way. However if he needs a declared bean, the language has the responsibility to make those beans avaialable "automatically."When a bean is declared it is automatically registered as well so that any declared bean can be gotton to by looking it up as well.
If any of the languages that are already running in this manager says they don't like this (by throwing an exception) then this method will simply quit with that exception. That is, any engines that come after than in the engine enumeration will not even be told about this new bean.
So, in general its best to declare beans before the manager has been asked to load any engines because then the user can be informed when an engine rejects it. Also, its much more likely that an engine can declare a bean at start time than it can at any time.
- Parameters:
beanName
- name to declare bean asbean
- the bean that's being declaredtype
- the type to represent the bean as- Throws:
BSFException
- if any of the languages that are already running decides to throw an exception when asked to declare this bean.
-
eval
public java.lang.Object eval(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object expr) throws BSFException
Evaluate the given expression of the given language and return the resulting value.- Parameters:
lang
- language identifiersource
- (context info) the source of this expression (e.g., filename)lineNo
- (context info) the line number in source for exprcolumnNo
- (context info) the column number in source for exprexpr
- the expression to evaluate- Throws:
BSFException
- if anything goes wrong while running the script
-
exec
public void exec(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object script) throws BSFException
Execute the given script of the given language.- Parameters:
lang
- language identifiersource
- (context info) the source of this expression (e.g., filename)lineNo
- (context info) the line number in source for exprcolumnNo
- (context info) the column number in source for exprscript
- the script to execute- Throws:
BSFException
- if anything goes wrong while running the script
-
iexec
public void iexec(java.lang.String lang, java.lang.String source, int lineNo, int columnNo, java.lang.Object script) throws BSFException
Execute the given script of the given language, attempting to emulate an interactive session w/ the language.- Parameters:
lang
- language identifiersource
- (context info) the source of this expression (e.g., filename)lineNo
- (context info) the line number in source for exprcolumnNo
- (context info) the column number in source for exprscript
- the script to execute- Throws:
BSFException
- if anything goes wrong while running the script
-
getClassLoader
public java.lang.ClassLoader getClassLoader()
Get classLoader
-
getClassPath
public java.lang.String getClassPath()
Get classPath
-
getLangFromFilename
public static java.lang.String getLangFromFilename(java.lang.String fileName) throws BSFException
Determine the language of a script file by looking at the file extension.- Parameters:
fileName
- the name of the file- Returns:
- the scripting language the file is in if the file extension is known to me (must have been registered via registerScriptingEngine).
- Throws:
BSFException
- if file's extension is unknown.
-
getObjectRegistry
public ObjectRegistry getObjectRegistry()
Return the current object registry of the manager.- Returns:
- the current registry.
-
getTempDir
public java.lang.String getTempDir()
Get tempDir
-
isLanguageRegistered
public static boolean isLanguageRegistered(java.lang.String lang)
Determine whether a language is registered.- Parameters:
lang
- string identifying a language- Returns:
- true iff it is
-
loadScriptingEngine
public BSFEngine loadScriptingEngine(java.lang.String lang) throws BSFException
Load a scripting engine based on the lang string identifying it.- Parameters:
lang
- string identifying language- Throws:
BSFException
- if the language is unknown (i.e., if it has not been registered) with a reason of REASON_UNKNOWN_LANGUAGE. If the language is known but if the interface can't be created for some reason, then the reason is set to REASON_OTHER_ERROR and the actual exception is passed on as well.
-
lookupBean
public java.lang.Object lookupBean(java.lang.String beanName)
return a handle to a bean registered in the bean registry by the application or a scripting engine. Returns null if bean is not found.- Parameters:
beanName
- name of bean to look up- Returns:
- the bean if its found or null
-
registerBean
public void registerBean(java.lang.String beanName, java.lang.Object bean)
Registering a bean allows a scripting engine or the application to access that bean by name and to manipulate it.- Parameters:
beanName
- name to register underbean
- the bean to register
-
registerScriptingEngine
public static void registerScriptingEngine(java.lang.String lang, java.lang.String engineClassName, java.lang.String[] extensions)
Register a scripting engine in the static registry of the BSFManager.- Parameters:
lang
- string identifying languageengineClassName
- fully qualified name of the class interfacing the language to BSF.extensions
- array of file extensions that should be mapped to this language type. may be null.
-
setClassLoader
public void setClassLoader(java.lang.ClassLoader classLoader)
Set the class loader for those that need to use it. Default is he who loaded me or null (i.e., its Class.forName).- Parameters:
classLoader
- the class loader to use.
-
setClassPath
public void setClassPath(java.lang.String classPath)
Set the classpath for those that need to use it. Default is the value of the java.class.path property.- Parameters:
classPath
- the classpath to use
-
setObjectRegistry
public void setObjectRegistry(ObjectRegistry objectRegistry)
Set the object registry used by this manager. By default a new one is created when the manager is new'ed and this overwrites that one.- Parameters:
objectRegistry
- the registry to use
-
setTempDir
public void setTempDir(java.lang.String tempDir)
Temporary directory to put stuff into (for those who need to). Note that unless this directory is in the classpath or unless the classloader knows to look in here, any classes here will not be found! BSFManager provides a service method to load a class which uses either the classLoader provided by the class loader property or, if that fails, a class loader which knows to load from the tempdir to try to load the class. Default value of tempDir is "." (current working dir).- Parameters:
tempDir
- the temporary directory
-
terminate
public void terminate()
Gracefully terminate all engines
-
undeclareBean
public void undeclareBean(java.lang.String beanName) throws BSFException
Undeclare a previously declared bean. This removes the bean from the list of declared beans in the manager as well as asks every running engine to undeclared the bean. As with above, if any of the engines except when asked to undeclare, this method does not catch that exception. Quietly returns if the bean is unknown.- Parameters:
beanName
- name of bean to undeclare- Throws:
BSFException
- if any of the languages that are already running decides to throw an exception when asked to undeclare this bean.
-
unregisterBean
public void unregisterBean(java.lang.String beanName)
Unregister a previously registered bean. Silent if name is not found.- Parameters:
beanName
- name of bean to unregister
-
-