Class EngineUtils


  • public class EngineUtils
    extends java.lang.Object
    This class contains utilities that language integrators can use when implementing the BSFEngine interface.
    Author:
    Sanjiva Weerawarana, Sam Ruby, Rony G. Flatscher (added addEventListenerReturningEventInfos)
    • Constructor Summary

      Constructors 
      Constructor Description
      EngineUtils()  
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static void addEventListener​(java.lang.Object bean, java.lang.String eventSetName, java.lang.String filter, BSFEngine engine, BSFManager manager, java.lang.String source, int lineNo, int columnNo, java.lang.Object script)
      Add a script as a listener to some event coming out of an object.
      static void addEventListenerReturningEventInfos​(java.lang.Object bean, java.lang.String eventSetName, java.lang.String filter, BSFEngine engine, BSFManager manager, java.lang.String source, int lineNo, int columnNo, java.lang.Object script, java.lang.Object dataFromScriptingEngine)
      Add a script as a listener to some event coming out of an object.
      static java.lang.Object callBeanMethod​(java.lang.Object bean, java.lang.String methodName, java.lang.Object[] args)
      Finds and invokes a method with the given signature on the given bean.
      static java.lang.Object createBean​(java.lang.String className, java.lang.Object[] args)
      Creates a new bean.
      static java.lang.String getTypeSignatureString​(java.lang.Class cl)
      Given a class return the type signature string fragment for it.
      static java.lang.Class loadClass​(BSFManager mgr, java.lang.String name)
      Load a class using the class loader of given manager.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • EngineUtils

        public EngineUtils()
    • Method Detail

      • addEventListener

        public static void addEventListener​(java.lang.Object bean,
                                            java.lang.String eventSetName,
                                            java.lang.String filter,
                                            BSFEngine engine,
                                            BSFManager manager,
                                            java.lang.String source,
                                            int lineNo,
                                            int columnNo,
                                            java.lang.Object script)
                                     throws BSFException
        Add a script as a listener to some event coming out of an object. The first two args identify the src of the event and the event set and the rest identify the script which should be run when the event fires.
        Parameters:
        bean - event source
        eventSetName - name of event set from event src to bind to
        filter - filter for events
        engine - BSFEngine which can run this script
        manager - BSFManager of the above engine
        source - (context info) the source of this expression (e.g., filename)
        lineNo - (context info) the line number in source for expr
        columnNo - (context info) the column number in source for expr
        script - the script to execute when the event occurs
        Throws:
        BSFException - if anything goes wrong while running the script
      • addEventListenerReturningEventInfos

        public static void addEventListenerReturningEventInfos​(java.lang.Object bean,
                                                               java.lang.String eventSetName,
                                                               java.lang.String filter,
                                                               BSFEngine engine,
                                                               BSFManager manager,
                                                               java.lang.String source,
                                                               int lineNo,
                                                               int columnNo,
                                                               java.lang.Object script,
                                                               java.lang.Object dataFromScriptingEngine)
                                                        throws BSFException
        Add a script as a listener to some event coming out of an object. The first two args identify the src of the event and the event set and the rest identify the script which should be run when the event fires. The processing will use the engine's apply() method.
        Parameters:
        bean - event source
        eventSetName - name of event set from event src to bind to
        filter - filter for events
        engine - BSFEngine which can run this script
        manager - BSFManager of the above engine
        source - (context info) the source of this expression (e.g., filename)
        lineNo - (context info) the line number in source for expr
        columnNo - (context info) the column number in source for expr
        script - the script to execute when the event occurs
        dataFromScriptingEngine - this contains any object supplied by the scripting engine and gets sent back with the supplied script, if the event occurs. This could be used e.g. for indicating to the scripting engine which scripting engine object/routine/function/procedure should be ultimately informed of the event occurrence.
        Throws:
        BSFException - if anything goes wrong while running the script
      • callBeanMethod

        public static java.lang.Object callBeanMethod​(java.lang.Object bean,
                                                      java.lang.String methodName,
                                                      java.lang.Object[] args)
                                               throws BSFException
        Finds and invokes a method with the given signature on the given bean. The signature of the method that's invoked is first taken as the types of the args, but if that fails, this tries to convert any primitive wrapper type args to their primitive counterparts to see whether a method exists that way. If it does, done.
        Parameters:
        bean - the object on which to invoke the method
        methodName - name of the method
        args - arguments to be given to the method
        Returns:
        the result of invoking the method, if any
        Throws:
        BSFException - if something goes wrong
      • createBean

        public static java.lang.Object createBean​(java.lang.String className,
                                                  java.lang.Object[] args)
                                           throws BSFException
        Creates a new bean. The signature of the constructor that's invoked is first taken as the types of the args, but if that fails, this tries to convert any primitive wrapper type args to their primitive counterparts to see whether a method exists that way. If it does, done.
        Parameters:
        className - fully qualified name of class to instantiate
        args - array of constructor args (or null if none)
        Returns:
        the created bean
        Throws:
        BSFException - if something goes wrong (@see org.apache.cs.util.MethodUtils for the real exceptions that can occur).
      • getTypeSignatureString

        public static java.lang.String getTypeSignatureString​(java.lang.Class cl)
        Given a class return the type signature string fragment for it. That is, return "I" for int, "J" for long, ... etc..
        Parameters:
        cl - class object for whom the signature fragment is needed.
        Returns:
        the string representing the type signature
      • loadClass

        public static java.lang.Class loadClass​(BSFManager mgr,
                                                java.lang.String name)
                                         throws BSFException
        Load a class using the class loader of given manager. If that fails try using a class loader that loads from the tempdir of the manager.
        Parameters:
        mgr - BSFManager who's classLoader and tempDir props are consulted
        name - name of the class to load
        Returns:
        the loaded class
        Throws:
        BSFException - if something goes wrong.