org.apache.velocity.runtime
Class RuntimeSingleton

java.lang.Object
  |
  +--org.apache.velocity.runtime.RuntimeSingleton

All Implemented Interfaces:

RuntimeConstants

public class RuntimeSingleton

extends java.lang.Object

implements RuntimeConstants

This is the Runtime system for Velocity. It is the single access point for all functionality in Velocity. It adheres to the mediator pattern and is the only structure that developers need to be familiar with in order to get Velocity to perform. The Runtime will also cooperate with external systems like Turbine. Runtime properties can set and then the Runtime is initialized. Turbine for example knows where the templates are to be loaded from, and where the velocity log file should be placed. So in the case of Velocity cooperating with Turbine the code might look something like the following:

 Runtime.setProperty(Runtime.FILE_RESOURCE_LOADER_PATH, templatePath);
 Runtime.setProperty(Runtime.RUNTIME_LOG, pathToVelocityLog);
 Runtime.init();
 

 -----------------------------------------------------------------------
 N O T E S  O N  R U N T I M E  I N I T I A L I Z A T I O N
 -----------------------------------------------------------------------
 Runtime.init()
 
 If Runtime.init() is called by itself the Runtime will
 initialize with a set of default values.
 -----------------------------------------------------------------------
 Runtime.init(String/Properties)

 In this case the default velocity properties are layed down
 first to provide a solid base, then any properties provided
 in the given properties object will override the corresponding
 default property.
 -----------------------------------------------------------------------
 

Version:

$Id: RuntimeSingleton.java,v 1.4 2001/10/31 02:59:28 geirm Exp $

Author:

Jason van Zyl, Jeff Bowden, Geir Magusson Jr.

Field Summary

private static RuntimeInstance

ri

Fields inherited from interface org.apache.velocity.runtime.RuntimeConstants

COUNTER_INITIAL_VALUE, COUNTER_NAME, DEBUG_PREFIX, DEFAULT_RUNTIME_DIRECTIVES, DEFAULT_RUNTIME_PROPERTIES, ENCODING_DEFAULT, ERROR_PREFIX, ERRORMSG_END, ERRORMSG_START, FILE_RESOURCE_LOADER_CACHE, FILE_RESOURCE_LOADER_PATH, INFO_PREFIX, INPUT_ENCODING, INTERPOLATE_STRINGLITERALS, LOGSYSTEM_LOG4J_EMAIL_BUFFER_SIZE, LOGSYSTEM_LOG4J_EMAIL_FROM, LOGSYSTEM_LOG4J_EMAIL_SERVER, LOGSYSTEM_LOG4J_EMAIL_SUBJECT, LOGSYSTEM_LOG4J_EMAIL_TO, LOGSYSTEM_LOG4J_FILE_BACKUPS, LOGSYSTEM_LOG4J_FILE_SIZE, LOGSYSTEM_LOG4J_PATTERN, LOGSYSTEM_LOG4J_REMOTE_HOST, LOGSYSTEM_LOG4J_REMOTE_PORT, LOGSYSTEM_LOG4J_SYSLOGD_FACILITY, LOGSYSTEM_LOG4J_SYSLOGD_HOST, NUMBER_OF_PARSERS, OUTPUT_ENCODING, PARSE_DIRECTIVE_MAXDEPTH, PARSER_POOL_SIZE, RESOURCE_LOADER, RESOURCE_MANAGER_CACHE_CLASS, RESOURCE_MANAGER_CLASS, RESOURCE_MANAGER_LOGWHENFOUND, RUNTIME_LOG, RUNTIME_LOG_ERROR_STACKTRACE, RUNTIME_LOG_INFO_STACKTRACE, RUNTIME_LOG_LOGSYSTEM, RUNTIME_LOG_LOGSYSTEM_CLASS, RUNTIME_LOG_REFERENCE_LOG_INVALID, RUNTIME_LOG_WARN_STACKTRACE, UNKNOWN_PREFIX, VM_CONTEXT_LOCALSCOPE, VM_LIBRARY, VM_LIBRARY_AUTORELOAD, VM_MESSAGES_ON, VM_PERM_ALLOW_INLINE, VM_PERM_ALLOW_INLINE_REPLACE_GLOBAL, VM_PERM_INLINE_LOCAL, WARN_PREFIX

Constructor Summary

RuntimeSingleton()

Method Summary

static void	addProperty(java.lang.String key, java.lang.Object value) Add a property to the configuration.
static boolean	addVelocimacro(java.lang.String name, java.lang.String macro, java.lang.String[] argArray, java.lang.String sourceTemplate) Adds a new Velocimacro.
static void	clearProperty(java.lang.String key) Clear the values pertaining to a particular property.
private static Parser	createNewParser() Returns a JavaCC generated Parser.
static void	debug(java.lang.Object message) Log a debug message.
static boolean	dumpVMNamespace(java.lang.String namespace) tells the vmFactory to dump the specified namespace.
static void	error(java.lang.Object message) Log an error message.
static boolean	getBoolean(java.lang.String key, boolean def) Boolean property accessor method to hide the configuration implementation.
static org.apache.commons.collections.ExtendedProperties	getConfiguration() Return the velocity runtime configuration object.
static ContentResource	getContent(java.lang.String name) Returns a static content resource from the resource manager.
static ContentResource	getContent(java.lang.String name, java.lang.String encoding) Returns a static content resource from the resource manager.
static int	getInt(java.lang.String key) Int property accessor method to hide the configuration implementation.
static int	getInt(java.lang.String key, int defaultValue) Int property accessor method to hide the configuration implementation.
static Introspector	getIntrospector() Return the Introspector for this RuntimeInstance
static java.lang.String	getLoaderNameForResource(java.lang.String resourceName) Determines is a template exists, and returns name of the loader that provides it.
static java.lang.Object	getProperty(java.lang.String key) Allows an external caller to get a property.
static RuntimeInstance	getRuntimeInstance() returns the RuntimeInstance object for this singleton For internal use only :)
static RuntimeServices	getRuntimeServices()
static java.lang.String	getString(java.lang.String key) String property accessor method to hide the configuration implementation
static java.lang.String	getString(java.lang.String key, java.lang.String defaultValue) String property accessor method with default to hide the configuration implementation.
static Template	getTemplate(java.lang.String name) Returns a Template from the resource manager.
static Template	getTemplate(java.lang.String name, java.lang.String encoding) Returns a Template from the resource manager
static Directive	getVelocimacro(java.lang.String vmName, java.lang.String templateName) Returns the appropriate VelocimacroProxy object if strVMname is a valid current Velocimacro.
static void	info(java.lang.Object message) Log an info message.
static void	init()
static void	init(java.util.Properties p) Initialize the Velocity Runtime with a Properties object.
static void	init(java.lang.String configurationFile) Initialize the Velocity Runtime with the name of ExtendedProperties object.
static boolean	isVelocimacro(java.lang.String vmName, java.lang.String templateName) Checks to see if a VM exists
static SimpleNode	parse(java.io.Reader reader, java.lang.String templateName) Parse the input and return the root of AST node structure.
static SimpleNode	parse(java.io.Reader reader, java.lang.String templateName, boolean dumpNamespace) Parse the input and return the root of the AST node structure.
static void	setConfiguration(org.apache.commons.collections.ExtendedProperties configuration) Allow an external system to set an ExtendedProperties object to use.
static void	setProperty(java.lang.String key, java.lang.Object value) Allows an external system to set a property in the Velocity Runtime.
static void	warn(java.lang.Object message) Log a warning message.

Methods inherited from class java.lang.Object

, clone, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, toString, wait, wait, wait

Field Detail

ri

private static RuntimeInstance ri

Constructor Detail

RuntimeSingleton

public RuntimeSingleton()

Method Detail

init

public static void init()
                 throws java.lang.Exception

getRuntimeServices

public static RuntimeServices getRuntimeServices()

setProperty

public static void setProperty(java.lang.String key,
                               java.lang.Object value)

Allows an external system to set a property in the Velocity Runtime.

Parameters:

String - property key

String - property value

setConfiguration

public static void setConfiguration(org.apache.commons.collections.ExtendedProperties configuration)

Allow an external system to set an ExtendedProperties object to use. This is useful where the external system also uses the ExtendedProperties class and the velocity configuration is a subset of parent application's configuration. This is the case with Turbine.

Parameters:

ExtendedProperties - configuration

addProperty

public static void addProperty(java.lang.String key,
                               java.lang.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:

String - key

String - value

clearProperty

public static void clearProperty(java.lang.String key)

Clear the values pertaining to a particular property.

Parameters:

String - key of property to clear

getProperty

public static java.lang.Object getProperty(java.lang.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

init

public static void init(java.util.Properties p)
                 throws java.lang.Exception

Initialize the Velocity Runtime with a Properties object.

Parameters:

Properties -

init

public static void init(java.lang.String configurationFile)
                 throws java.lang.Exception

Initialize the Velocity Runtime with the name of ExtendedProperties object.

Parameters:

Properties -

createNewParser

private static Parser createNewParser()

Returns a JavaCC generated Parser.

Returns:

Parser javacc generated parser

parse

public static SimpleNode parse(java.io.Reader reader,
                               java.lang.String templateName)
                        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:

InputStream - inputstream retrieved by a resource loader

String - name of the template being parsed

parse

public static SimpleNode parse(java.io.Reader reader,
                               java.lang.String templateName,
                               boolean dumpNamespace)
                        throws ParseException

Parse the input and return the root of the AST node structure.

Parameters:

InputStream - inputstream retrieved by a resource loader

String - name of the template being parsed

dumpNamespace - flag to dump the Velocimacro namespace for this template

getTemplate

public static Template getTemplate(java.lang.String name)
                            throws ResourceNotFoundException,
                                   ParseErrorException,
                                   java.lang.Exception

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 "ISO-8859-1"

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.

java.lang.Exception - if an error occurs in template initialization

getTemplate

public static Template getTemplate(java.lang.String name,
                                   java.lang.String encoding)
                            throws ResourceNotFoundException,
                                   ParseErrorException,
                                   java.lang.Exception

Returns a Template from the resource manager

Parameters:

name - The name of the desired template.

encoding - Character encoding of the 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.

java.lang.Exception - if an error occurs in template initialization

getContent

public static ContentResource getContent(java.lang.String name)
                                  throws ResourceNotFoundException,
                                         ParseErrorException,
                                         java.lang.Exception

Returns a static content resource from the resource manager. Uses the current value if INPUT_ENCODING as the character encoding.

Parameters:

name - Name of content resource to get

Returns:

parsed ContentResource object ready for use

Throws:

ResourceNotFoundException - if template not found from any available source.

getContent

public static ContentResource getContent(java.lang.String name,
                                         java.lang.String encoding)
                                  throws ResourceNotFoundException,
                                         ParseErrorException,
                                         java.lang.Exception

Returns a static content resource from the resource manager.

Parameters:

name - Name of content resource to get

encoding - Character encoding to use

Returns:

parsed ContentResource object ready for use

Throws:

ResourceNotFoundException - if template not found from any available source.

getLoaderNameForResource

public static java.lang.String getLoaderNameForResource(java.lang.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

warn

public static void warn(java.lang.Object message)

Log a warning message.

Parameters:

Object - message to log

info

public static void info(java.lang.Object message)

Log an info message.

Parameters:

Object - message to log

error

public static void error(java.lang.Object message)

Log an error message.

Parameters:

Object - message to log

debug

public static void debug(java.lang.Object message)

Log a debug message.

Parameters:

Object - message to log

getString

public static java.lang.String getString(java.lang.String key,
                                         java.lang.String defaultValue)

String property accessor method with default to hide the configuration implementation.

Parameters:

String - key property key

String - defaultValue default value to return if key not found in resource manager.

Returns:

String value of key or default

getVelocimacro

public static Directive getVelocimacro(java.lang.String vmName,
                                       java.lang.String templateName)

Returns the appropriate VelocimacroProxy object if strVMname is a valid current Velocimacro.

Parameters:

String - vmName Name of velocimacro requested

Returns:

String VelocimacroProxy

addVelocimacro

public static boolean addVelocimacro(java.lang.String name,
                                     java.lang.String macro,
                                     java.lang.String[] argArray,
                                     java.lang.String sourceTemplate)

Adds a new Velocimacro. Usually called by Macro only while parsing.

Parameters:

String - name Name of velocimacro

String - macro String form of macro body

String - argArray Array of strings, containing the #macro() arguments. the 0th is the name.

Returns:

boolean True if added, false if rejected for some reason (either parameters or permission settings)

isVelocimacro

public static boolean isVelocimacro(java.lang.String vmName,
                                    java.lang.String templateName)

Checks to see if a VM exists

Parameters:

name - Name of velocimacro

Returns:

boolean True if VM by that name exists, false if not

dumpVMNamespace

public static boolean dumpVMNamespace(java.lang.String namespace)

tells the vmFactory to dump the specified namespace. This is to support clearing the VM list when in inline-VM-local-scope mode

getString

public static java.lang.String getString(java.lang.String key)

String property accessor method to hide the configuration implementation

Parameters:

key - property key

Returns:

value of key or null

getInt

public static int getInt(java.lang.String key)

Int property accessor method to hide the configuration implementation.

Parameters:

String - key property key

Returns:

int value

getInt

public static int getInt(java.lang.String key,
                         int defaultValue)

Int property accessor method to hide the configuration implementation.

Parameters:

key - property key

int - default value

Returns:

int value

getBoolean

public static boolean getBoolean(java.lang.String key,
                                 boolean def)

Boolean property accessor method to hide the configuration implementation.

Parameters:

String - key property key

boolean - default default value if property not found

Returns:

boolean value of key or default value

getConfiguration

public static org.apache.commons.collections.ExtendedProperties getConfiguration()

Return the velocity runtime configuration object.

Returns:

ExtendedProperties configuration object which houses the velocity runtime properties.

getIntrospector

public static Introspector getIntrospector()

Return the Introspector for this RuntimeInstance

Returns:

Introspector object for this runtime instance

getRuntimeInstance

public static RuntimeInstance getRuntimeInstance()

returns the RuntimeInstance object for this singleton For internal use only :)

Returns:

RuntimeInstance the RuntimeInstance used by this Singleton instance