Class DynamicLoader

  • All Implemented Interfaces:
    IDynamicLoader

    public class DynamicLoader
    extends Object
    implements IDynamicLoader
    Utility class used to perform dynamic loading of user-hook implementations
    • Constructor Detail

      • DynamicLoader

        public DynamicLoader()
    • Method Detail

      • registerKnownClasses

        protected void registerKnownClasses()
        Register classes that might be dynamically loaded even though they are contained within Saxon itself. This typically occurs for default implementations of classes that can be substituted or subclassed by the user.
      • setClassLoader

        public void setClassLoader​(ClassLoader loader)
        Set a ClassLoader to be used when loading external classes. Examples of classes that are loaded include SAX parsers, localization modules for formatting numbers and dates, extension functions, external object models. In an environment such as Eclipse that uses its own ClassLoader, this ClassLoader should be nominated to ensure that any class loaded by Saxon is identical to a class of the same name loaded by the external environment.
        Specified by:
        setClassLoader in interface IDynamicLoader
        Parameters:
        loader - the ClassLoader to be used in this configuration
      • getClass

        public Class<?> getClass​(String className,
                                 Logger traceOut,
                                 ClassLoader classLoader)
                          throws XPathException
        Load a class using the class name provided. Note that the method does not check that the object is of the right class.

        This method is intended for internal use only.

        Specified by:
        getClass in interface IDynamicLoader
        Parameters:
        className - A string containing the name of the class, for example "com.microstar.sax.LarkDriver"
        traceOut - if diagnostic tracing is required, the destination for the output; otherwise null
        classLoader - The ClassLoader to be used to load the class. If this is null, then the classLoader used will be the first one available of: the classLoader registered with the Configuration using setClassLoader(java.lang.ClassLoader); the context class loader for the current thread; or failing that, the class loader invoked implicitly by a call of Class.forName() (which is the ClassLoader that was used to load the Configuration object itself).
        Returns:
        an instance of the class named, or null if it is not loadable.
        Throws:
        XPathException - if the class cannot be loaded.
      • getInstance

        public Object getInstance​(String className,
                                  ClassLoader classLoader)
                           throws XPathException
        Instantiate a class using the class name provided. Note that the method does not check that the object is of the right class.

        This method is intended for internal use only.

        Specified by:
        getInstance in interface IDynamicLoader
        Parameters:
        className - A string containing the name of the class, for example "com.microstar.sax.LarkDriver"
        classLoader - The ClassLoader to be used to load the class. If this is null, then the classLoader used will be the first one available of: the classLoader registered with the Configuration using setClassLoader(java.lang.ClassLoader); the context class loader for the current thread; or failing that, the class loader invoked implicitly by a call of Class.forName() (which is the ClassLoader that was used to load the Configuration object itself).
        Returns:
        an instance of the class named, or null if it is not loadable.
        Throws:
        XPathException - if the class cannot be loaded.
      • getInstance

        public Object getInstance​(String className,
                                  Logger traceOut,
                                  ClassLoader classLoader)
                           throws XPathException
        Instantiate a class using the class name provided, with the option of tracing Note that the method does not check that the object is of the right class.

        This method is intended for internal use only.

        Specified by:
        getInstance in interface IDynamicLoader
        Parameters:
        className - A string containing the name of the class, for example "com.microstar.sax.LarkDriver"
        traceOut - if attempts to load classes are to be traced, then the destination for the trace output; otherwise null
        classLoader - The ClassLoader to be used to load the class. If this is null, then the classLoader used will be the first one available of: the classLoader registered with the Configuration using setClassLoader(java.lang.ClassLoader); the context class loader for the current thread; or failing that, the class loader invoked implicitly by a call of Class.forName() (which is the ClassLoader that was used to load the Configuration object itself).
        Returns:
        an instance of the class named, or null if it is not loadable.
        Throws:
        XPathException - if the class cannot be loaded.
      • getResourceAsStream

        public InputStream getResourceAsStream​(String name)
        Description copied from interface: IDynamicLoader
        Get a resource from a supplied URI using the classpath URI scheme.
        Specified by:
        getResourceAsStream in interface IDynamicLoader
        Parameters:
        name - the path name from the URI
        Returns:
        the content of the relevant resource