package org.apache.velocity.runtime; /* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ import org.apache.velocity.Template; import org.apache.velocity.app.event.EventCartridge; import org.apache.velocity.app.event.EventHandler; import org.apache.velocity.app.event.IncludeEventHandler; import org.apache.velocity.app.event.InvalidReferenceEventHandler; import org.apache.velocity.app.event.MethodExceptionEventHandler; import org.apache.velocity.app.event.ReferenceInsertionEventHandler; import org.apache.velocity.context.Context; import org.apache.velocity.context.InternalContextAdapterImpl; import org.apache.velocity.exception.MethodInvocationException; import org.apache.velocity.exception.ParseErrorException; import org.apache.velocity.exception.ResourceNotFoundException; import org.apache.velocity.exception.TemplateInitException; import org.apache.velocity.exception.VelocityException; import org.apache.velocity.runtime.directive.Directive; import org.apache.velocity.runtime.directive.Macro; import org.apache.velocity.runtime.directive.Scope; import org.apache.velocity.runtime.directive.StopCommand; import org.apache.velocity.runtime.parser.LogContext; import org.apache.velocity.runtime.parser.ParseException; import org.apache.velocity.runtime.parser.Parser; import org.apache.velocity.runtime.parser.node.Node; import org.apache.velocity.runtime.parser.node.SimpleNode; import org.apache.velocity.runtime.resource.ContentResource; import org.apache.velocity.runtime.resource.ResourceManager; import org.apache.velocity.util.ClassUtils; import org.apache.velocity.util.ExtProperties; import org.apache.velocity.util.RuntimeServicesAware; import org.apache.velocity.util.introspection.ChainableUberspector; import org.apache.velocity.util.introspection.LinkingUberspector; import org.apache.velocity.util.introspection.Uberspect; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.IOException; import java.io.InputStream; import java.io.Reader; import java.io.StringReader; import java.io.Writer; import java.lang.reflect.Constructor; import java.lang.reflect.InvocationTargetException; import java.nio.charset.StandardCharsets; import java.util.Enumeration; import java.util.HashMap; import java.util.HashSet; import java.util.Hashtable; import java.util.Iterator; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.NoSuchElementException; import java.util.Properties; import java.util.Set; /** *

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, which can make all needed setProperty() calls * before calling 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
 * -----------------------------------------------------------------------
 * init()
 *
 * If init() is called by itself the RuntimeInstance will initialize
 * with a set of default values.
 * -----------------------------------------------------------------------
 * 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.
 * -----------------------------------------------------------------------
 * 
* * @author Jason van Zyl * @author Jeff Bowden * @author Geir Magusson Jr. * @version $Id$ */ public class RuntimeInstance implements RuntimeConstants, RuntimeServices { /** * VelocimacroFactory object to manage VMs */ private VelocimacroFactory vmFactory = null; /** * The Runtime logger. The default instance is the "org.apache.velocity" logger. */ private Logger log = LoggerFactory.getLogger(DEFAULT_RUNTIME_LOG_NAME); /** * The Runtime parser pool */ private ParserPool parserPool; /** * Indicate whether the Runtime is in the midst of initialization. */ private boolean initializing = false; /** * Indicate whether the Runtime has been fully initialized. */ private volatile boolean initialized = false; /** * These are the properties that are laid down over top * of the default properties when requested. */ private ExtProperties overridingProperties = null; /** * This is a hashtable of initialized directives. * The directives that populate this hashtable are * taken from the RUNTIME_DEFAULT_DIRECTIVES * property file. */ private Map runtimeDirectives = new Hashtable(); /** * Copy of the actual runtimeDirectives that is shared between * parsers. Whenever directives are updated, the synchronized * runtimeDirectives is first updated and then an unsynchronized * copy of it is passed to parsers. */ private Map runtimeDirectivesShared; /** * Object that houses the configuration options for * the velocity runtime. The ExtProperties object allows * the convenient retrieval of a subset of properties. * For example all the properties for a resource loader * can be retrieved from the main ExtProperties object * using something like the following: * * ExtProperties loaderConfiguration = * configuration.subset(loaderID); * * And a configuration is a lot more convenient to deal * with then conventional properties objects, or Maps. */ private ExtProperties configuration = new ExtProperties(); private ResourceManager resourceManager = null; /** * This stores the engine-wide set of event handlers. Event handlers for * each specific merge are stored in the context. */ private EventCartridge eventCartridge = null; /** * Whether to use string interning */ private boolean stringInterning = false; /** * Scope name for evaluate(...) calls. */ private String evaluateScopeName = "evaluate"; /** * Scope names for which to provide scope control objects in the context */ private Set enabledScopeControls = new HashSet(); /** * Opaque reference to something specified by the * application for use in application supplied/specified * pluggable components */ private Map applicationAttributes = null; /** * Uberspector */ private Uberspect uberSpect; /** * Default encoding */ private String defaultEncoding; /** * Space gobbling mode */ private SpaceGobbling spaceGobbling; /** * Whether hyphen is allowed in identifiers */ private boolean hyphenAllowedInIdentifiers; /** * The LogContext object used to track location in templates */ private LogContext logContext; /** * Configured parser class * @since 2.2 */ private Constructor parserConstructor; /** * Configured replacement characters in parser grammar * @since 2.2 */ private ParserConfiguration parserConfiguration; /** * Creates a new RuntimeInstance object. */ public RuntimeInstance() { reset(); } /** * This is the primary initialization method in the Velocity * Runtime. The systems that are setup/initialized here are * as follows: * * */ public synchronized void init() { if (!initialized && !initializing) { try { log.debug("Initializing Velocity, Calling init()..."); initializing = true; log.trace("*****************************"); log.debug("Starting Apache Velocity v2.0"); log.trace("RuntimeInstance initializing."); initializeProperties(); initializeSelfProperties(); initializeLog(); initializeResourceManager(); initializeDirectives(); initializeEventHandlers(); initializeParserPool(); initializeIntrospection(); initializeScopeSettings(); /* * initialize the VM Factory. It will use the properties * accessible from Runtime, so keep this here at the end. */ vmFactory.initVelocimacro(); log.trace("RuntimeInstance successfully initialized."); initialized = true; initializing = false; } catch(RuntimeException re) { // initialization failed at some point... try to reset everything try { reset(); } catch(RuntimeException re2) {} // prefer throwing the original exception throw re; } finally { initializing = false; } } } /** * Resets the instance, so Velocity can be re-initialized again. * * @since 2.0.0 */ public synchronized void reset() { this.configuration = new ExtProperties(); this.defaultEncoding = null; this.evaluateScopeName = "evaluate"; this.eventCartridge = null; this.initialized = false; this.initializing = false; this.overridingProperties = null; this.parserPool = null; this.enabledScopeControls.clear(); this.resourceManager = null; this.runtimeDirectives = new Hashtable(); this.runtimeDirectivesShared = null; this.uberSpect = null; this.stringInterning = false; this.parserConfiguration = new ParserConfiguration(); /* * create a VM factory, introspector, and application attributes */ vmFactory = new VelocimacroFactory( this ); /* * and a store for the application attributes */ applicationAttributes = new HashMap(); } /** * Returns true if the RuntimeInstance has been successfully initialized. * @return True if the RuntimeInstance has been successfully initialized. * @since 1.5 */ public boolean isInitialized() { return initialized; } /** * Init or die! (with some log help, of course) */ private void requireInitialization() { if (!initialized) { try { init(); } catch (Exception e) { log.error("Could not auto-initialize Velocity", e); throw new RuntimeException("Velocity could not be initialized!", e); } } } /** * Initialize runtime internal properties */ private void initializeSelfProperties() { /* initialize string interning (defaults to false) */ stringInterning = getBoolean(RUNTIME_STRING_INTERNING, true); /* initialize indentation mode (defaults to 'lines') */ String im = getString(SPACE_GOBBLING, "lines"); try { spaceGobbling = SpaceGobbling.valueOf(im.toUpperCase(Locale.ROOT)); } catch (NoSuchElementException nse) { spaceGobbling = SpaceGobbling.LINES; } /* init parser behavior */ hyphenAllowedInIdentifiers = getBoolean(PARSER_HYPHEN_ALLOWED, false); } private char getConfiguredCharacter(String configKey, char defaultChar) { String configuredChar = getString(configKey); if (configuredChar != null) { if (configuredChar.length() != 1) { throw new RuntimeException(configKey + " must be a single UTF-8 character"); } return configuredChar.charAt(0); } return defaultChar; } /** * Gets the classname for the Uberspect introspection package and * instantiates an instance. */ private void initializeIntrospection() { String[] uberspectors = configuration.getStringArray(RuntimeConstants.UBERSPECT_CLASSNAME); for (String rm : uberspectors) { Object o = null; try { o = ClassUtils.getNewInstance(rm); } catch (ClassNotFoundException cnfe) { String err = "The specified class for Uberspect (" + rm + ") does not exist or is not accessible to the current classloader."; log.error(err); throw new VelocityException(err, cnfe); } catch (InstantiationException ie) { throw new VelocityException("Could not instantiate class '" + rm + "'", ie); } catch (IllegalAccessException ae) { throw new VelocityException("Cannot access class '" + rm + "'", ae); } if (!(o instanceof Uberspect)) { String err = "The specified class for Uberspect (" + rm + ") does not implement " + Uberspect.class.getName() + "; Velocity is not initialized correctly."; log.error(err); throw new VelocityException(err); } Uberspect u = (Uberspect) o; if (u instanceof RuntimeServicesAware) { ((RuntimeServicesAware) u).setRuntimeServices(this); } if (uberSpect == null) { uberSpect = u; } else { if (u instanceof ChainableUberspector) { ((ChainableUberspector) u).wrap(uberSpect); uberSpect = u; } else { uberSpect = new LinkingUberspector(uberSpect, u); } } } if(uberSpect != null) { uberSpect.init(); } else { /* * someone screwed up. Lets not fool around... */ String err = "It appears that no class was specified as the" + " Uberspect. Please ensure that all configuration" + " information is correct."; log.error(err); throw new VelocityException(err); } } /** * Initializes the Velocity Runtime with properties file. * The properties file may be in the file system proper, * or the properties file may be in the classpath. */ private void setDefaultProperties() { InputStream inputStream = null; try { inputStream = getClass().getClassLoader() .getResourceAsStream(DEFAULT_RUNTIME_PROPERTIES); if (inputStream == null) throw new IOException("Resource not found: " + DEFAULT_RUNTIME_PROPERTIES); configuration.load( inputStream ); /* populate 'defaultEncoding' member */ defaultEncoding = getString(INPUT_ENCODING, ENCODING_DEFAULT); log.debug("Default Properties resource: {}", DEFAULT_RUNTIME_PROPERTIES); } catch (IOException ioe) { String msg = "Cannot get Velocity Runtime default properties!"; log.error(msg, ioe); throw new RuntimeException(msg, ioe); } finally { try { if (inputStream != null) { inputStream.close(); } } catch (IOException ioe) { String msg = "Cannot close Velocity Runtime default properties!"; log.error(msg, ioe); throw new RuntimeException(msg, ioe); } } } /** * Allows an external system to set a property in * the Velocity Runtime. * * @param key property key * @param value property value */ public void setProperty(String key, Object value) { if (overridingProperties == null) { overridingProperties = new ExtProperties(); } overridingProperties.setProperty(key, value); } /** * Add all properties contained in the file fileName to the RuntimeInstance properties * @param fileName */ public void setProperties(String fileName) { ExtProperties props = null; try { props = new ExtProperties(fileName); } catch (IOException e) { throw new VelocityException("Error reading properties from '" + fileName + "'", e); } Enumeration en = props.keys(); while (en.hasMoreElements()) { String key = en.nextElement().toString(); setProperty(key, props.get(key)); } } /** * Add all the properties in props to the RuntimeInstance properties * @param props */ public void setProperties(Properties props) { Enumeration en = props.keys(); while (en.hasMoreElements()) { String key = en.nextElement().toString(); setProperty(key, props.get(key)); } } /** * Allow an external system to set an ExtProperties * object to use. * * @param configuration * @since 2.0 */ public void setConfiguration( ExtProperties configuration) { if (overridingProperties == null) { overridingProperties = configuration; } else { // Avoid possible ConcurrentModificationException if (overridingProperties != configuration) { overridingProperties.combine(configuration); } } } /** * 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"] * * @param key * @param value */ public void addProperty(String key, Object value) { if (overridingProperties == null) { overridingProperties = new ExtProperties(); } overridingProperties.addProperty(key, value); } /** * Clear the values pertaining to a particular * property. * * @param key of property to clear */ public void clearProperty(String key) { if (overridingProperties != null) { overridingProperties.clearProperty(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. * * @param key property to return * @return Value of the property or null if it does not exist. */ public Object getProperty(String key) { Object o = null; /** * Before initialization, check the user-entered properties first. */ if (!initialized && overridingProperties != null) { o = overridingProperties.get(key); } /** * After initialization, configuration will hold all properties. */ if (o == null) { o = configuration.getProperty(key); } if (o instanceof String) { return StringUtils.trim((String) o); } else { return o; } } /** * Initialize Velocity properties, if the default * properties have not been laid down first then * do so. Then proceed to process any overriding * properties. Laying down the default properties * gives a much greater chance of having a * working system. */ private void initializeProperties() { /* * Always lay down the default properties first as * to provide a solid base. */ if (configuration.isInitialized() == false) { setDefaultProperties(); } if( overridingProperties != null) { configuration.combine(overridingProperties); } } /** * Initialize the Velocity Runtime with a Properties * object. * * @param p Velocity properties for initialization */ public void init(Properties p) { setConfiguration(ExtProperties.convertProperties(p)); init(); } /** * Initialize the Velocity Runtime with a * properties file path. * * @param configurationFile */ public void init(String configurationFile) { setProperties(configurationFile); init(); } private void initializeResourceManager() { /* * Which resource manager? */ Object inst = getProperty(RuntimeConstants.RESOURCE_MANAGER_INSTANCE); String rm = getString(RuntimeConstants.RESOURCE_MANAGER_CLASS); if (inst != null) { if (ResourceManager.class.isAssignableFrom(inst.getClass())) { resourceManager = (ResourceManager)inst; resourceManager.initialize(this); } else { String msg = inst.getClass().getName() + " object set as resource.manager.instance is not a valid org.apache.velocity.runtime.resource.ResourceManager."; log.error(msg); throw new VelocityException(msg); } } else if (rm != null && rm.length() > 0) { /* * if something was specified, then make one. * if that isn't a ResourceManager, consider * this a huge error and throw */ Object o = null; try { o = ClassUtils.getNewInstance( rm ); } catch (ClassNotFoundException cnfe ) { String err = "The specified class for ResourceManager (" + rm + ") does not exist or is not accessible to the current classloader."; log.error(err); throw new VelocityException(err, cnfe); } catch (InstantiationException ie) { throw new VelocityException("Could not instantiate class '" + rm + "'", ie); } catch (IllegalAccessException ae) { throw new VelocityException("Cannot access class '" + rm + "'", ae); } if (!(o instanceof ResourceManager)) { String err = "The specified class for ResourceManager (" + rm + ") does not implement " + ResourceManager.class.getName() + "; Velocity is not initialized correctly."; log.error(err); throw new VelocityException(err); } resourceManager = (ResourceManager) o; resourceManager.initialize(this); setProperty(RESOURCE_MANAGER_INSTANCE, resourceManager); } else { /* * someone screwed up. Lets not fool around... */ String err = "It appears that no class or instance was specified as the" + " ResourceManager. Please ensure that all configuration" + " information is correct."; log.error(err); throw new VelocityException( err ); } } private void initializeEventHandlers() { eventCartridge = new EventCartridge(); eventCartridge.setRuntimeServices(this); /** * For each type of event handler, get the class name, instantiate it, and store it. */ String[] referenceinsertion = configuration.getStringArray(RuntimeConstants.EVENTHANDLER_REFERENCEINSERTION); if ( referenceinsertion != null ) { for (String aReferenceinsertion : referenceinsertion) { EventHandler ev = initializeSpecificEventHandler(aReferenceinsertion, RuntimeConstants.EVENTHANDLER_REFERENCEINSERTION, ReferenceInsertionEventHandler.class); if (ev != null) eventCartridge.addReferenceInsertionEventHandler((ReferenceInsertionEventHandler) ev); } } String[] methodexception = configuration.getStringArray(RuntimeConstants.EVENTHANDLER_METHODEXCEPTION); if ( methodexception != null ) { for (String aMethodexception : methodexception) { EventHandler ev = initializeSpecificEventHandler(aMethodexception, RuntimeConstants.EVENTHANDLER_METHODEXCEPTION, MethodExceptionEventHandler.class); if (ev != null) eventCartridge.addMethodExceptionHandler((MethodExceptionEventHandler) ev); } } String[] includeHandler = configuration.getStringArray(RuntimeConstants.EVENTHANDLER_INCLUDE); if ( includeHandler != null ) { for (String anIncludeHandler : includeHandler) { EventHandler ev = initializeSpecificEventHandler(anIncludeHandler, RuntimeConstants.EVENTHANDLER_INCLUDE, IncludeEventHandler.class); if (ev != null) eventCartridge.addIncludeEventHandler((IncludeEventHandler) ev); } } String[] invalidReferenceSet = configuration.getStringArray(RuntimeConstants.EVENTHANDLER_INVALIDREFERENCES); if ( invalidReferenceSet != null ) { for (String anInvalidReferenceSet : invalidReferenceSet) { EventHandler ev = initializeSpecificEventHandler(anInvalidReferenceSet, RuntimeConstants.EVENTHANDLER_INVALIDREFERENCES, InvalidReferenceEventHandler.class); if (ev != null) { eventCartridge.addInvalidReferenceEventHandler((InvalidReferenceEventHandler) ev); } } } } private EventHandler initializeSpecificEventHandler(String classname, String paramName, Class EventHandlerInterface) { if ( classname != null && classname.length() > 0) { Object o = null; try { o = ClassUtils.getNewInstance(classname); } catch (ClassNotFoundException cnfe ) { String err = "The specified class for " + paramName + " (" + classname + ") does not exist or is not accessible to the current classloader."; log.error(err); throw new VelocityException(err, cnfe); } catch (InstantiationException ie) { throw new VelocityException("Could not instantiate class '" + classname + "'", ie); } catch (IllegalAccessException ae) { throw new VelocityException("Cannot access class '" + classname + "'", ae); } if (!EventHandlerInterface.isAssignableFrom(EventHandlerInterface)) { String err = "The specified class for " + paramName + " (" + classname + ") does not implement " + EventHandlerInterface.getName() + "; Velocity is not initialized correctly."; log.error(err); throw new VelocityException(err); } EventHandler ev = (EventHandler) o; if ( ev instanceof RuntimeServicesAware ) ((RuntimeServicesAware) ev).setRuntimeServices(this); return ev; } else return null; } /** * Initialize the Velocity logging system. */ private void initializeLog() { // if we were provided a specific logger or logger name, let's use it try { /* If a Logger instance was set as a configuration * value, use that. This is any class the user specifies. */ Object o = getProperty(RuntimeConstants.RUNTIME_LOG_INSTANCE); if (o != null) { // check for a Logger if (Logger.class.isAssignableFrom(o.getClass())) { //looks ok log = (Logger)o; } else { String msg = o.getClass().getName() + " object set as runtime.log.instance is not a valid org.slf4j.Logger implementation."; log.error(msg); throw new VelocityException(msg); } } else { /* otherwise, see if a logger name was specified. */ o = getProperty(RuntimeConstants.RUNTIME_LOG_NAME); if (o != null) { if (o instanceof String) { log = LoggerFactory.getLogger((String)o); } else { String msg = o.getClass().getName() + " object set as runtime.log.name is not a valid string."; log.error(msg); throw new VelocityException(msg); } } } /* else keep our default Velocity logger */ /* Initialize LogContext */ boolean trackLocation = getBoolean(RUNTIME_LOG_TRACK_LOCATION, false); logContext = new LogContext(trackLocation); } catch (Exception e) { throw new VelocityException("Error initializing log: " + e.getMessage(), e); } } /** * This methods initializes all the directives * that are used by the Velocity Runtime. The * directives to be initialized are listed in * the RUNTIME_DEFAULT_DIRECTIVES properties * file. */ private void initializeDirectives() { Properties directiveProperties = new Properties(); /* * Grab the properties file with the list of directives * that we should initialize. */ InputStream inputStream = null; try { inputStream = getClass().getResourceAsStream('/' + DEFAULT_RUNTIME_DIRECTIVES); if (inputStream == null) { throw new VelocityException("Error loading directive.properties! " + "Something is very wrong if these properties " + "aren't being located. Either your Velocity " + "distribution is incomplete or your Velocity " + "jar file is corrupted!"); } directiveProperties.load(inputStream); } catch (IOException ioe) { String msg = "Error while loading directive properties!"; log.error(msg, ioe); throw new RuntimeException(msg, ioe); } finally { try { if (inputStream != null) { inputStream.close(); } } catch (IOException ioe) { String msg = "Cannot close directive properties!"; log.error(msg, ioe); throw new RuntimeException(msg, ioe); } } /* * Grab all the values of the properties. These * are all class names for example: * * org.apache.velocity.runtime.directive.Foreach */ Enumeration directiveClasses = directiveProperties.elements(); while (directiveClasses.hasMoreElements()) { String directiveClass = (String) directiveClasses.nextElement(); loadDirective(directiveClass); log.debug("Loaded System Directive: {}", directiveClass); } /* * now the user's directives */ String[] userdirective = configuration.getStringArray(CUSTOM_DIRECTIVES); for (String anUserdirective : userdirective) { loadDirective(anUserdirective); log.debug("Loaded User Directive: {}", anUserdirective); } } /** * Programatically add a directive. * @param directive */ public synchronized void addDirective(Directive directive) { runtimeDirectives.put(directive.getName(), directive); updateSharedDirectivesMap(); } /** * Retrieve a previously instantiated directive. * @param name name of the directive * @return the {@link Directive} for that name */ public Directive getDirective(String name) { return (Directive) runtimeDirectivesShared.get(name); } /** * Remove a directive. * @param name name of the directive. */ public synchronized void removeDirective(String name) { runtimeDirectives.remove(name); updateSharedDirectivesMap(); } /** * Makes an unsynchronized copy of the directives map * that is used for Directive lookups by all parsers. * * This follows Copy-on-Write pattern. The cost of creating * a new map is acceptable since directives are typically * set and modified only during Velocity setup phase. */ private void updateSharedDirectivesMap() { runtimeDirectivesShared = new HashMap(runtimeDirectives); } /** * instantiates and loads the directive with some basic checks * * @param directiveClass classname of directive to load */ public void loadDirective(String directiveClass) { try { Object o = ClassUtils.getNewInstance( directiveClass ); if (o instanceof Directive) { Directive directive = (Directive) o; addDirective(directive); } else { String msg = directiveClass + " does not implement " + Directive.class.getName() + "; it cannot be loaded."; log.error(msg); throw new VelocityException(msg); } } // The ugly threesome: ClassNotFoundException, // IllegalAccessException, InstantiationException. // Ignore Findbugs complaint for now. catch (Exception e) { String msg = "Failed to load Directive: " + directiveClass; log.error(msg, e); throw new VelocityException(msg, e); } } /** * Initializes the Velocity parser pool. */ private void initializeParserPool() { /* * First initialize parser class. If it's not valid or not found, it will generate an error * later on in this method when parser creation is tester. */ String parserClassName = getString(PARSER_CLASS, DEFAULT_PARSER_CLASS); Class parserClass; try { parserClass = ClassUtils.getClass(parserClassName); } catch (ClassNotFoundException cnfe) { throw new VelocityException("parser class not found: " + parserClassName, cnfe); } try { parserConstructor = parserClass.getConstructor(RuntimeServices.class); } catch (NoSuchMethodException nsme) { throw new VelocityException("parser class must provide a constructor taking a RuntimeServices argument", nsme); } /* * Which parser pool? */ String pp = getString(RuntimeConstants.PARSER_POOL_CLASS); if (pp != null && pp.length() > 0) { /* * if something was specified, then make one. * if that isn't a ParserPool, consider * this a huge error and throw */ Object o = null; try { o = ClassUtils.getNewInstance( pp ); } catch (ClassNotFoundException cnfe ) { String err = "The specified class for ParserPool (" + pp + ") does not exist (or is not accessible to the current classloader."; log.error(err); throw new VelocityException(err, cnfe); } catch (InstantiationException ie) { throw new VelocityException("Could not instantiate class '" + pp + "'", ie); } catch (IllegalAccessException ae) { throw new VelocityException("Cannot access class '" + pp + "'", ae); } if (!(o instanceof ParserPool)) { String err = "The specified class for ParserPool (" + pp + ") does not implement " + ParserPool.class + " Velocity not initialized correctly."; log.error(err); throw new VelocityException(err); } parserPool = (ParserPool) o; parserPool.initialize(this); /* * test parser creation and use generated parser to fill up customized characters */ Parser parser = parserPool.get(); parserConfiguration = new ParserConfiguration(); parserConfiguration.setDollarChar(parser.dollar()); parserConfiguration.setHashChar(parser.hash()); parserConfiguration.setAtChar(parser.at()); parserConfiguration.setAsteriskChar(parser.asterisk()); parserPool.put(parser); } else { /* * someone screwed up. Lets not fool around... */ String err = "It appears that no class was specified as the" + " ParserPool. Please ensure that all configuration" + " information is correct."; log.error(err); throw new VelocityException( err ); } } /** * Returns a JavaCC generated Parser. * * @return Parser javacc generated parser */ public Parser createNewParser() { requireInitialization(); try { return (Parser)parserConstructor.newInstance((RuntimeServices)this); } catch (IllegalAccessException | InstantiationException | InvocationTargetException e) { throw new VelocityException("could not build new parser class", e); } } /** * 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. * * @param reader Reader retrieved by a resource loader * @param template template being parsed * @return A root node representing the template as an AST tree. * @throws ParseException When the template could not be parsed. */ public SimpleNode parse(Reader reader, Template template) throws ParseException { requireInitialization(); Parser parser = parserPool.get(); boolean keepParser = true; if (parser == null) { /* * if we couldn't get a parser from the pool make one and log it. */ log.info("Runtime: ran out of parsers. Creating a new one. " + " Please increment the parser.pool.size property." + " The current value is too small."); parser = createNewParser(); keepParser = false; } try { return parser.parse(reader, template); } finally { if (keepParser) { /* drop the parser Template reference to allow garbage collection */ parser.resetCurrentTemplate(); parserPool.put(parser); } } } private void initializeScopeSettings() { ExtProperties scopes = configuration.subset(CONTEXT_SCOPE_CONTROL); if (scopes != null) { Iterator scopeIterator = scopes.getKeys(); while (scopeIterator.hasNext()) { String scope = scopeIterator.next(); boolean enabled = scopes.getBoolean(scope); if (enabled) enabledScopeControls.add(scope); } } } /** * 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. *
* Note! Macros defined in evaluate() calls are not persisted in memory so next evaluate() call * does not know about macros defined during previous calls. * * @param context context to use in rendering input string * @param out Writer in which to render the output * @param logTag string to be used as the template name for log * messages in case of error * @param instring input string containing the VTL to be rendered * * @return true if successful, false otherwise. If false, see * Velocity runtime log * @throws ParseErrorException The template could not be parsed. * @throws MethodInvocationException A method on a context object could not be invoked. * @throws ResourceNotFoundException A referenced resource could not be loaded. * @since Velocity 1.6 */ public boolean evaluate(Context context, Writer out, String logTag, String instring) { return evaluate(context, out, logTag, new StringReader(instring)); } /** * 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. *
* Note! Macros defined in evaluate() calls are not persisted in memory so next evaluate() call * does not know about macros defined during previous calls. * * @param context context to use in rendering input string * @param writer Writer in which to render the output * @param logTag string to be used as the template name for log messages * in case of error * @param reader Reader containing the VTL to be rendered * * @return true if successful, false otherwise. If false, see * Velocity runtime log * @throws ParseErrorException The template could not be parsed. * @throws MethodInvocationException A method on a context object could not be invoked. * @throws ResourceNotFoundException A referenced resource could not be loaded. * @since Velocity 1.6 */ public boolean evaluate(Context context, Writer writer, String logTag, Reader reader) { if (logTag == null) { throw new NullPointerException("logTag (i.e. template name) cannot be null, you must provide an identifier for the content being evaluated"); } SimpleNode nodeTree = null; Template t = new Template(); t.setName(logTag); try { nodeTree = parse(reader, t); } catch (ParseException pex) { throw new ParseErrorException(pex, null); } catch (TemplateInitException pex) { throw new ParseErrorException(pex, null); } if (nodeTree == null) { return false; } else { return render(context, writer, logTag, nodeTree); } } /** * Initializes and renders the AST {@link SimpleNode} using the context * into the output writer. * * @param context context to use in rendering input string * @param writer Writer in which to render the output * @param logTag string to be used as the template name for log messages * in case of error * @param nodeTree SimpleNode which is the root of the AST to be rendered * * @return true if successful, false otherwise. If false, see * Velocity runtime log for errors * @throws ParseErrorException The template could not be parsed. * @throws MethodInvocationException A method on a context object could not be invoked. * @throws ResourceNotFoundException A referenced resource could not be loaded. * @since Velocity 1.6 */ public boolean render(Context context, Writer writer, String logTag, SimpleNode nodeTree) { /* * we want to init then render */ InternalContextAdapterImpl ica = new InternalContextAdapterImpl(context); ica.pushCurrentTemplateName(logTag); try { try { nodeTree.init(ica, this); } catch (TemplateInitException pex) { throw new ParseErrorException(pex, null); } /** * pass through application level runtime exceptions */ catch(RuntimeException e) { throw e; } catch(Exception e) { String msg = "RuntimeInstance.render(): init exception for tag = "+logTag; log.error(msg, e); throw new VelocityException(msg, e); } try { if (isScopeControlEnabled(evaluateScopeName)) { Object previous = ica.get(evaluateScopeName); context.put(evaluateScopeName, new Scope(this, previous)); } /** * optionally put the context in itself if asked so */ String self = getString(CONTEXT_AUTOREFERENCE_KEY); if (self != null) context.put(self, context); nodeTree.render(ica, writer); } catch (StopCommand stop) { if (!stop.isFor(this)) { throw stop; } else { log.debug(stop.getMessage()); } } catch (IOException e) { throw new VelocityException("IO Error in writer: " + e.getMessage(), e); } } finally { ica.popCurrentTemplateName(); if (isScopeControlEnabled(evaluateScopeName)) { Object obj = ica.get(evaluateScopeName); if (obj instanceof Scope) { Scope scope = (Scope)obj; if (scope.getParent() != null) { ica.put(evaluateScopeName, scope.getParent()); } else if (scope.getReplaced() != null) { ica.put(evaluateScopeName, scope.getReplaced()); } else { ica.remove(evaluateScopeName); } } } } return true; } /** * 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. *
* Note: only macros in the global context can be called. This method doesn't find macros defined by * templates during previous mergeTemplate calls if Velocity.VM_PERM_INLINE_LOCAL has been enabled. * * @param vmName name of Velocimacro to call * @param logTag string to be used for template name in case of error. if null, * the vmName will be used * @param params keys for args used to invoke Velocimacro, in java format * rather than VTL (eg "foo" or "bar" rather than "$foo" or "$bar") * @param context Context object containing data/objects used for rendering. * @param writer Writer for output stream * @return true if Velocimacro exists and successfully invoked, false otherwise. * @since 1.6 */ public boolean invokeVelocimacro(final String vmName, String logTag, String[] params, final Context context, final Writer writer) { /* check necessary parameters */ if (vmName == null || context == null || writer == null) { String msg = "RuntimeInstance.invokeVelocimacro(): invalid call: vmName, context, and writer must not be null"; log.error(msg); throw new NullPointerException(msg); } /* handle easily corrected parameters */ if (logTag == null) { logTag = vmName; } if (params == null) { params = new String[0]; } /* does the VM exist? (only global scope is scanned so this doesn't find inline macros in templates) */ if (!isVelocimacro(vmName, null)) { String msg = "RuntimeInstance.invokeVelocimacro(): VM '" + vmName + "' is not registered."; log.error(msg); throw new VelocityException(msg); } /* now just create the VM call, and use evaluate */ StringBuilder template = new StringBuilder(String.valueOf(parserConfiguration.getHashChar())); template.append(vmName); template.append("("); for (String param : params) { template.append(" $"); template.append(param); } template.append(" )"); return evaluate(context, writer, logTag, template.toString()); } /** * Retrieves and caches the configured default encoding * for better performance. (VELOCITY-606) */ private String getDefaultEncoding() { return defaultEncoding; } /** * Returns a Template from the resource manager. * This method assumes that the character encoding of the * template is set by the resource.default_encoding * property. The default is UTF-8. * * @param name The file name of the desired template. * @return The template. * @throws ResourceNotFoundException if template not found * from any available source. * @throws ParseErrorException if template cannot be parsed due * to syntax (or other) error. */ public Template getTemplate(String name) throws ResourceNotFoundException, ParseErrorException { return getTemplate(name, null); } /** * Returns a Template from the resource manager * * @param name The name of the desired template. * @param encoding Character encoding of the template * @return The template. * @throws ResourceNotFoundException if template not found * from any available source. * @throws ParseErrorException if template cannot be parsed due * to syntax (or other) error. */ public Template getTemplate(String name, String encoding) throws ResourceNotFoundException, ParseErrorException { requireInitialization(); if (encoding == null) encoding = getDefaultEncoding(); return (Template) resourceManager.getResource(name, ResourceManager.RESOURCE_TEMPLATE, encoding); } /** * Returns a static content resource from the * resource manager. Uses the current value * if INPUT_ENCODING as the character encoding. * * @param name Name of content resource to get * @return parsed ContentResource object ready for use * @throws ResourceNotFoundException if template not found * from any available source. * @throws ParseErrorException When the template could not be parsed. */ public ContentResource getContent(String name) throws ResourceNotFoundException, ParseErrorException { /* * the encoding is irrelvant as we don't do any converstion * the bytestream should be dumped to the output stream */ return getContent(name, getDefaultEncoding()); } /** * Returns a static content resource from the * resource manager. * * @param name Name of content resource to get * @param encoding Character encoding to use * @return parsed ContentResource object ready for use * @throws ResourceNotFoundException if template not found * from any available source. * @throws ParseErrorException When the template could not be parsed. */ public ContentResource getContent(String name, String encoding) throws ResourceNotFoundException, ParseErrorException { requireInitialization(); return (ContentResource) resourceManager.getResource(name, ResourceManager.RESOURCE_CONTENT, encoding); } /** * Determines if a template exists and returns name of the loader that * provides it. This is a slightly less hokey way to support * the Velocity.resourceExists() utility method, which was broken * when per-template encoding was introduced. We can revisit this. * * @param resourceName Name of template or content resource * @return class name of loader than can provide it */ public String getLoaderNameForResource(String resourceName) { requireInitialization(); return resourceManager.getLoaderNameForResource(resourceName); } /** * Returns the configured logger. * * @return A Logger instance * @since 1.5 */ public Logger getLog() { return log; } /** * 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. * @param childNamespace * @return child namespace logger */ public Logger getLog(String childNamespace) { Logger log = (Logger)getProperty(RuntimeConstants.RUNTIME_LOG_INSTANCE); if (log == null) { String loggerName = getString(RUNTIME_LOG_NAME, DEFAULT_RUNTIME_LOG_NAME) + "." + childNamespace; log = LoggerFactory.getLogger(loggerName); } return log; } /** * Get the LogContext object used to tack locations in templates. * @return LogContext object * @since 2.2 */ public LogContext getLogContext() { return logContext; } /** * String property accessor method with default to hide the * configuration implementation. * * @param key property key * @param defaultValue default value to return if key not * found in resource manager. * @return value of key or default */ public String getString( String key, String defaultValue) { return configuration.getString(key, defaultValue); } /** * Returns the appropriate VelocimacroProxy object if vmName * is a valid current Velocimacro. * * @param vmName Name of velocimacro requested * @param 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. * @param template Template which acts as the host for the macro * * @return VelocimacroProxy */ public Directive getVelocimacro(String vmName, Template renderingTemplate, Template template) { return vmFactory.getVelocimacro(vmName, renderingTemplate, template); } /** * Adds a new Velocimacro. Usually called by Macro only while parsing. * * @param name Name of velocimacro * @param macro root AST node of the parsed macro * @param macroArgs Array of macro arguments, containing the * #macro() arguments and default values. the 0th is the name. * @param definingTemplate Template containing the source of the macro * * @return boolean True if added, false if rejected for some * reason (either parameters or permission settings) */ public boolean addVelocimacro( String name, Node macro, List macroArgs, Template definingTemplate) { return vmFactory.addVelocimacro(stringInterning ? name.intern() : name, macro, macroArgs, definingTemplate); } /** * Checks to see if a VM exists * * @param vmName Name of the Velocimacro. * @param template Template on which to look for the Macro. * @return True if VM by that name exists, false if not */ public boolean isVelocimacro(String vmName, Template template) { return vmFactory.isVelocimacro(stringInterning ? vmName.intern() : vmName, template); } /* -------------------------------------------------------------------- * R U N T I M E A C C E S S O R M E T H O D S * -------------------------------------------------------------------- * These are the getXXX() methods that are a simple wrapper * around the configuration object. This is an attempt * to make a the Velocity Runtime the single access point * for all things Velocity, and allow the Runtime to * adhere as closely as possible the the Mediator pattern * which is the ultimate goal. * -------------------------------------------------------------------- */ /** * String property accessor method to hide the configuration implementation * @param key property key * @return value of key or null */ public String getString(String key) { return StringUtils.trim(configuration.getString(key)); } /** * Int property accessor method to hide the configuration implementation. * * @param key Property key * @return value */ public int getInt(String key) { return configuration.getInt(key); } /** * Int property accessor method to hide the configuration implementation. * * @param key property key * @param defaultValue The default value. * @return value */ public int getInt(String key, int defaultValue) { return configuration.getInt(key, defaultValue); } /** * Boolean property accessor method to hide the configuration implementation. * * @param key property key * @param def The default value if property not found. * @return value of key or default value */ public boolean getBoolean(String key, boolean def) { return configuration.getBoolean(key, def); } /** * Return the velocity runtime configuration object. * * @return Configuration object which houses the Velocity runtime * properties. */ public ExtProperties getConfiguration() { return configuration; } /** * Returns the event handlers for the application. * @return The event handlers for the application. * @since 1.5 */ public EventCartridge getApplicationEventCartridge() { return eventCartridge; } /** * Gets the application attribute for the given key * * @param key * @return The application attribute for the given key. */ public Object getApplicationAttribute(Object key) { return applicationAttributes.get(key); } /** * Sets the application attribute for the given key * * @param key * @param o The new application attribute. * @return The old value of this attribute or null if it hasn't been set before. */ public Object setApplicationAttribute(Object key, Object o) { return applicationAttributes.put(key, o); } /** * Returns the Uberspect object for this Instance. * * @return The Uberspect object for this Instance. */ public Uberspect getUberspect() { return uberSpect; } /** * Whether to use string interning * * @return boolean */ public boolean useStringInterning() { return stringInterning; } /** * get space gobbling mode * @return indentation mode */ public SpaceGobbling getSpaceGobbling() { return spaceGobbling; } /** * get whether hyphens are allowed in identifiers * @return configured boolean flag */ public boolean isHyphenAllowedInIdentifiers() { return hyphenAllowedInIdentifiers; } /** * Get whether to provide a scope control object for this scope * @param scopeName * @return scope control enabled * @since 2.1 */ public boolean isScopeControlEnabled(String scopeName) { return enabledScopeControls.contains(scopeName); } @Override public ParserConfiguration getParserConfiguration() { return parserConfiguration; } }