Package org.apache.velocity.runtime

Interface RuntimeServices

  • All Known Implementing Classes:
    RuntimeInstance
    public interface RuntimeServices
    Interface for internal runtime services that are needed by the various components w/in Velocity. This was taken from the old Runtime singleton, and anything not necessary was removed. Currently implemented by RuntimeInstance.
    Version:
    $Id$
    Author:
    Geir Magusson Jr.

    • Method Detail

      • init

        void init()
        This is the primary initialization method in the Velocity Runtime. The systems that are setup/initialized here are as follows:
        • Logging System
        • ResourceManager
        • Parser Pool
        • Global Cache
        • Static Content Include System
        • Velocimacro System

      • setProperty

        void setProperty​(String key,
                 Object value)
        Allows an external system to set a property in the Velocity Runtime.
        Parameters:
        key - property key
        value - property value

      • setConfiguration

        void setConfiguration​(ExtProperties configuration)
        Allow an external system to set an ExtProperties object to use.
        Parameters:
        configuration -
        Since:
        2.0

      • addProperty

        void addProperty​(String key,
                 Object value)
        Add a property to the configuration. If it already exists then the value stated here will be added to the configuration entry. For example, if resource.loader = file is already present in the configuration and you addProperty("resource.loader", "classpath") Then you will end up with a Vector like the following: ["file", "classpath"]
        Parameters:
        key -
        value -

      • clearProperty

        void clearProperty​(String key)
        Clear the values pertaining to a particular property.
        Parameters:
        key - of property to clear

      • getProperty

        Object getProperty​(String key)
        Allows an external caller to get a property. The calling routine is required to know the type, as this routine will return an Object, as that is what properties can be.
        Parameters:
        key - property to return
        Returns:
        The value.

      • init

        void init​(Properties p)
        Initialize the Velocity Runtime with a Properties object.
        Parameters:
        p -

      • init

        void init​(String configurationFile)
        Initialize the Velocity Runtime with the name of ExtProperties object.
        Parameters:
        configurationFile -

      • parse

        SimpleNode parse​(Reader reader,
                 Template template)
          throws ParseException
        Parse the input and return the root of AST node structure.

        In the event that it runs out of parsers in the pool, it will create and let them be GC'd dynamically, logging that it has to do that. This is considered an exceptional condition. It is expected that the user will set the PARSER_POOL_SIZE property appropriately for their application. We will revisit this.
        Parameters:
        reader - inputstream retrieved by a resource loader
        template - template being parsed
        Returns:
        The AST representing the template.
        Throws:
        ParseException

      • evaluate

        boolean evaluate​(Context context,
                 Writer out,
                 String logTag,
                 String instring)
        Renders the input string using the context into the output writer. To be used when a template is dynamically constructed, or want to use Velocity as a token replacer.
        Parameters:
        context - context to use in rendering input string
        out - Writer in which to render the output
        logTag - string to be used as the template name for log messages in case of error
        instring - input string containing the VTL to be rendered
        Returns:
        true if successful, false otherwise. If false, see Velocity runtime log
        Throws:
        ParseErrorException - The template could not be parsed.
        MethodInvocationException - A method on a context object could not be invoked.
        ResourceNotFoundException - A referenced resource could not be loaded.
        Since:
        Velocity 1.6

      • evaluate

        boolean evaluate​(Context context,
                 Writer writer,
                 String logTag,
                 Reader reader)
        Renders the input reader using the context into the output writer. To be used when a template is dynamically constructed, or want to use Velocity as a token replacer.
        Parameters:
        context - context to use in rendering input string
        writer - Writer in which to render the output
        logTag - string to be used as the template name for log messages in case of error
        reader - Reader containing the VTL to be rendered
        Returns:
        true if successful, false otherwise. If false, see Velocity runtime log
        Throws:
        ParseErrorException - The template could not be parsed.
        MethodInvocationException - A method on a context object could not be invoked.
        ResourceNotFoundException - A referenced resource could not be loaded.
        Since:
        Velocity 1.6

      • invokeVelocimacro

        boolean invokeVelocimacro​(String vmName,
                          String logTag,
                          String[] params,
                          Context context,
                          Writer writer)
        Invokes a currently registered Velocimacro with the params provided and places the rendered stream into the writer.
        Note : currently only accepts args to the VM if they are in the context.
        Parameters:
        vmName - name of Velocimacro to call
        logTag - string to be used for template name in case of error. if null, the vmName will be used
        params - keys for args used to invoke Velocimacro, in java format rather than VTL (eg "foo" or "bar" rather than "$foo" or "$bar")
        context - Context object containing data/objects used for rendering.
        writer - Writer for output stream
        Returns:
        true if Velocimacro exists and successfully invoked, false otherwise.
        Since:
        1.6

      • getTemplate

        Template getTemplate​(String name)
              throws ResourceNotFoundException,
                     ParseErrorException
        Returns a Template from the resource manager. This method assumes that the character encoding of the template is set by the input.encoding property. The default is UTF-8.
        Parameters:
        name - The file name of the desired template.
        Returns:
        The template.
        Throws:
        ResourceNotFoundException - if template not found from any available source.
        ParseErrorException - if template cannot be parsed due to syntax (or other) error.

      • getLoaderNameForResource

        String getLoaderNameForResource​(String resourceName)
        Determines is a template exists, and returns name of the loader that provides it. This is a slightly less hokey way to support the Velocity.templateExists() utility method, which was broken when per-template encoding was introduced. We can revisit this.
        Parameters:
        resourceName - Name of template or content resource
        Returns:
        class name of loader than can provide it

      • getString

        String getString​(String key,
                 String defaultValue)
        String property accessor method with default to hide the configuration implementation.
        Parameters:
        key - property key
        defaultValue - default value to return if key not found in resource manager.
        Returns:
        String value of key or default

      • getVelocimacro

        Directive getVelocimacro​(String vmName,
                         Template renderingTemplate,
                         Template template)
        Returns the appropriate VelocimacroProxy object if strVMname is a valid current Velocimacro.
        Parameters:
        vmName - Name of velocimacro requested
        renderingTemplate - Template we are currently rendering. This information is needed when VM_PERM_ALLOW_INLINE_REPLACE_GLOBAL setting is true and template contains a macro with the same name as the global macro library.
        template - current template
        Returns:
        VelocimacroProxy

      • addVelocimacro

        boolean addVelocimacro​(String name,
                       Node macro,
                       List<Macro.MacroArg> macroArgs,
                       Template definingTemplate)
        Adds a new Velocimacro. Usually called by Macro only while parsing.
        Parameters:
        name - Name of velocimacro
        macro - root AST node of the parsed macro
        macroArgs - Array of macro arguments, containing the #macro() arguments and default values. the 0th is the name.
        definingTemplate - template containing macro definition
        Returns:
        boolean True if added, false if rejected for some reason (either parameters or permission settings)

      • isVelocimacro

        boolean isVelocimacro​(String vmName,
                      Template template)
        Checks to see if a VM exists
        Parameters:
        vmName - Name of velocimacro
        template - Template "namespace"
        Returns:
        boolean True if VM by that name exists, false if not

      • getString

        String getString​(String key)
        String property accessor method to hide the configuration implementation
        Parameters:
        key - property key
        Returns:
        value of key or null

      • getInt

        int getInt​(String key)
        Int property accessor method to hide the configuration implementation.
        Parameters:
        key - property key
        Returns:
        int value

      • getInt

        int getInt​(String key,
           int defaultValue)
        Int property accessor method to hide the configuration implementation.
        Parameters:
        key - property key
        defaultValue - default value
        Returns:
        int value

      • getBoolean

        boolean getBoolean​(String key,
                   boolean def)
        Boolean property accessor method to hide the configuration implementation.
        Parameters:
        key - property key
        def - default default value if property not found
        Returns:
        boolean value of key or default value

      • getConfiguration

        ExtProperties getConfiguration()
        Return the velocity runtime configuration object.
        Returns:
        ExtProperties configuration object which houses the velocity runtime properties.

      • getApplicationAttribute

        Object getApplicationAttribute​(Object key)
        Return the specified application attribute.
        Parameters:
        key - The name of the attribute to retrieve.
        Returns:
        The value of the attribute.

      • setApplicationAttribute

        Object setApplicationAttribute​(Object key,
                               Object value)
        Set the specified application attribute.
        Parameters:
        key - The name of the attribute to set.
        value - The attribute value to set.
        Returns:
        the displaced attribute value

      • getUberspect

        Uberspect getUberspect()
        Returns the configured class introspection/reflection implementation.
        Returns:
        The current Uberspect object.

      • getLog

        org.slf4j.Logger getLog()
        Returns the configured logger.
        Returns:
        A Logger object.

      • getLog

        org.slf4j.Logger getLog​(String childNamespace)
        Get a logger for the specified child namespace. If a logger was configured using the runtime.log.instance configuration property, returns this instance. Otherwise, uses SLF4J LoggerFactory on baseNamespace + childNamespace.
        Parameters:
        childNamespace -
        Returns:
        child name space logger

      • getLogContext

        LogContext getLogContext()
        Get the LogContext object used to tack locations in templates.
        Returns:
        LogContext object
        Since:
        2.2

      • getApplicationEventCartridge

        EventCartridge getApplicationEventCartridge()
        Returns the event handlers for the application.
        Returns:
        The event handlers for the application.

      • isInitialized

        boolean isInitialized()
        Returns true if the RuntimeInstance has been successfully initialized.
        Returns:
        True if the RuntimeInstance has been successfully initialized.

      • createNewParser

        Parser createNewParser()
        Create a new parser instance.
        Returns:
        A new parser instance.

      • getDirective

        Directive getDirective​(String name)
        Retrieve a previously instantiated directive.
        Parameters:
        name - name of the directive
        Returns:
        the directive with that name, if any
        Since:
        1.6

      • useStringInterning

        boolean useStringInterning()
        Check whether the engine uses string interning
        Returns:
        true if string interning is active

      • isHyphenAllowedInIdentifiers

        boolean isHyphenAllowedInIdentifiers()
        Get whether hyphens are allowed in identifiers
        Returns:
        configured boolean flag
        Since:
        2.1

      • isScopeControlEnabled

        boolean isScopeControlEnabled​(String scopeName)
        Get whether to provide a scope control object for this scope
        Parameters:
        scopeName -
        Returns:
        scope control enabled
        Since:
        2.1

      • getParserConfiguration

        ParserConfiguration getParserConfiguration()
        Get the replacement characters configured for this runtime service's parser
        Returns:
        configured replacement characters
        Since:
        2.2