    001// Licensed under the Apache License, Version 2.0 (the "License");
    002// you may not use this file except in compliance with the License.
    003// You may obtain a copy of the License at
    004//
    005// http://www.apache.org/licenses/LICENSE-2.0
    006//
    007// Unless required by applicable law or agreed to in writing, software
    008// distributed under the License is distributed on an "AS IS" BASIS,
    009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    010// See the License for the specific language governing permissions and
    011// limitations under the License.
    012
    013package org.apache.tapestry5;
    014
    015import org.apache.tapestry5.corelib.base.AbstractField;
    016import org.apache.tapestry5.corelib.components.BeanEditForm;
    017import org.apache.tapestry5.corelib.components.BeanEditor;
    018import org.apache.tapestry5.corelib.mixins.FormGroup;
    019import org.apache.tapestry5.internal.services.AssetDispatcher;
    020import org.apache.tapestry5.services.Html5Support;
    021import org.apache.tapestry5.services.assets.AssetPathConstructor;
    022import org.apache.tapestry5.services.assets.ResourceMinimizer;
    023import org.apache.tapestry5.services.javascript.JavaScriptStack;
    024
    025/**
    026 * Defines the names of symbols used to configure Tapestry.
    027 *
    028 * @see org.apache.tapestry5.ioc.services.SymbolSource
    029 */
    030public class SymbolConstants
    031{
    032    /**
    033     * A comma separated list of execution modes used to control how the application is initialized.
    034     * Each modes can contribute a list (comma separated) of Module classes to be loaded during startup,
    035     * the order in which they appear is preserved.
    036     * The default value is: <code>production</code>.
    037     */
    038    public static final String EXECUTION_MODE = "tapestry.execution-mode";
    039    /**
    040     * Indicates whether Tapestry is running in production mode or developer mode. This affects a large
    041     * number of Tapestry behaviors related to performance and security, including how exceptions are
    042     * reported, whether far-future expire headers are emitted, whether JavaScript files may be combined,
    043     * whether JSON is compressed, whether component field and parameter values are shadowed to instance
    044     * variables (to assist with debugging), and more.
    045     */
    046    public static final String PRODUCTION_MODE = "tapestry.production-mode";
    047
    048    /**
    049     * A version of {@link #PRODUCTION_MODE} as a symbol reference. This can be used as the default value
    050     * of other symbols, to indicate that their default matches whatever PRODUCTION_MODE is set to, which is quite
    051     * common.
    052     *
    053     * @since 5.2.0
    054     */
    055    public static final String PRODUCTION_MODE_VALUE = String.format("${%s}", PRODUCTION_MODE);
    056
    057    /**
    058     * The list of locales supported by the application; locales identified in the incoming request are "narrowed" to
    059     * one of these values. The first locale name in the list is the default locale used when no proper match can be
    060     * found.
    061     */
    062    public static final String SUPPORTED_LOCALES = "tapestry.supported-locales";
    063
    064    /**
    065     * Controls whether whitespace is compressed by default in templates, or left as is. The factory default is to
    066     * compress whitespace. (This can also be overridden using the xml:space attribute inside template elements.)
    067     */
    068    public static final String COMPRESS_WHITESPACE = "tapestry.compress-whitespace";
    069
    070    /**
    071     * Time interval defining how often Tapestry will check for updates to local files (including classes).
    072     * Starting with 5.3, this is only used when not running in production mode. The default is "1 s"
    073     * (one second), which is appropriate for development. With Tapestry 5.2 and earlier this number
    074     * should be raised in a production environment.
    075     */
    076    public static final String FILE_CHECK_INTERVAL = "tapestry.file-check-interval";
    077
    078    /**
    079     * Time interval that sets how long Tapestry will wait to obtain the exclusive lock needed to check local files. The
    080     * default is "50 ms". Starting with 5.3, this is only used when not running in production mode.
    081     */
    082    public static final String FILE_CHECK_UPDATE_TIMEOUT = "tapestry.file-check-update-timeout";
    083
    084    /**
    085     * The version number of the core Tapestry framework, or UNKNOWN if the version number is not available (which
    086     * should only occur when developing Tapestry).
    087     */
    088    public static final String TAPESTRY_VERSION = "tapestry.version";
    089
    090    /**
    091     * The location of the application-wide component messages catalog, relative to the web application context. This
    092     * will normally be <code>WEB-INF/app.properties</code>.
    093     */
    094    public static final String APPLICATION_CATALOG = "tapestry.app-catalog";
    095
    096    /**
    097     * The charset used when rendering page markup; the charset is also used as the request encoding when handling
    098     * incoming requests. The default is "UTF-8".
    099     */
    100    public static final String CHARSET = "tapestry.charset";
    101
    102    /**
    103     * Used as the default for the Form's autofocus and clientValidation parameters. If overridden to "false", then
    104     * Forms will not (unless explicitly specified) use client validation or autofocus, which in turn, means that most
    105     * pages with Forms will not make use of the Tapestry JavaScript stack.
    106     */
    107    public static final String FORM_CLIENT_LOGIC_ENABLED = "tapestry.form-client-logic-enabled";
    108
    109    /**
    110     * Name of page used to report exceptions; the page must implement
    111     * {@link org.apache.tapestry5.services.ExceptionReporter}.
    112     * This is used by the default exception report handler service.
    113     */
    114    public static final String EXCEPTION_REPORT_PAGE = "tapestry.exception-report-page";
    115
    116    /**
    117     * Identifies the default persistence strategy for all pages that do not provide an override (using this value as
    118     * {@link org.apache.tapestry5.annotations.Meta key}).
    119     *
    120     * @since 5.1.0.0
    121     */
    122    public static final String PERSISTENCE_STRATEGY = "tapestry.persistence-strategy";
    123
    124    /**
    125     * Minimum output stream size, in bytes, before output is compressed using GZIP. Shorter streams are not compressed.
    126     * Tapestry buffers this amount and switches to a GZIP output stream as needed. The default is "100".
    127     *
    128     * @see #GZIP_COMPRESSION_ENABLED
    129     * @since 5.1.0.0
    130     */
    131    public static final String MIN_GZIP_SIZE = "tapestry.min-gzip-size";
    132
    133    /**
    134     * Version number of the application. Prior to 5.4, this version number was integrated into asset URLs. Starting
    135     * with 5.4, a checksum of the individual asset's content is used instead, and this version number is only used
    136     * for documentation purposes; it appears in the default exception report page, for example.
    137     *
    138     * The default value is "0.0.1".  In 5.3 and earlier, the default value was a random hexadecimal string.
    139     *
    140     * @see AssetDispatcher
    141     * @see AssetPathConstructor
    142     * @since 5.1.0.0
    143     */
    144    public static final String APPLICATION_VERSION = "tapestry.application-version";
    145
    146    /**
    147     * Used to omit the normal Tapestry framework generator meta tag. The meta tag is rendered by default, but clients
    148     * who do not wish to advertise their use of Tapestry may set this symbol to "true".
    149     *
    150     * @since 5.1.0.0
    151     */
    152    public static final String OMIT_GENERATOR_META = "tapestry.omit-generator-meta";
    153
    154    /**
    155     * If "true" (the default) then GZip compression is enabled for dynamic requests and for static assets. If you are
    156     * using a server that handles GZip compression for you, or you don't want to use the extra processing power
    157     * necessary to GZIP requests, then override this to "false".
    158     *
    159     * @see #MIN_GZIP_SIZE
    160     * @see org.apache.tapestry5.services.ResponseCompressionAnalyzer
    161     * @see org.apache.tapestry5.services.assets.CompressionAnalyzer
    162     * @since 5.1.0.0
    163     */
    164    public static final String GZIP_COMPRESSION_ENABLED = "tapestry.gzip-compression-enabled";
    165
    166    /**
    167     * If "true" (which itself defaults to production mode), then the {@link org.apache.tapestry5.annotations.Secure}
    168     * annotation will be honored. If "false" (i.e., development mode), then the annotation and related HTTP/HTTPS
    169     * logic is ignored.
    170     *
    171     * @since 5.1.0.1
    172     */
    173    public static final String SECURE_ENABLED = "tapestry.secure-enabled";
    174
    175    /**
    176     * If "true" (the default), then the {@link org.apache.tapestry5.services.PersistentLocale} will be encoded into the
    177     * {@link org.apache.tapestry5.Link} path by the {@link org.apache.tapestry5.services.ComponentEventLinkEncoder}
    178     * service. If overridden to "false" this does not occur, but you should provide a
    179     * {@link org.apache.tapestry5.services.LinkCreationListener2} (registered with the
    180     * {@link org.apache.tapestry5.services.LinkCreationHub}) in order to add the locale as a query parameter (or
    181     * provide some alternate means of persisting the locale between requests).
    182     *
    183     * @since 5.1.0.1
    184     */
    185    public static final String ENCODE_LOCALE_INTO_PATH = "tapestry.encode-locale-into-path";
    186
    187    /**
    188     * If "true" then JavaScript files in a {@link JavaScriptStack} will be combined into a single virtual JavaScript
    189     * file. Defaults to "true" in production mode.
    190     *
    191     * @since 5.1.0.2
    192     */
    193    public static final String COMBINE_SCRIPTS = "tapestry.combine-scripts";
    194
    195
    196    /**
    197     * The default time interval that cookies created by Tapestry will be kept in the client web browser. The default is
    198     * "7 d" (that is, seven days).
    199     *
    200     * @since 5.2.0
    201     */
    202    public static final String COOKIE_MAX_AGE = "tapestry.default-cookie-max-age";
    203
    204    /**
    205     * The logical name of the start page, the page that is rendered for the root URL.
    206     *
    207     * @since 5.2.0
    208     */
    209    public static final String START_PAGE_NAME = "tapestry.start-page-name";
    210
    211    /**
    212     * The default stylesheet automatically inserted into every rendered HTML page.
    213     *
    214     * @since 5.2.0
    215     * @deprecated Deprecated in 5.4 with no replacement; the stylesheet is now associated with the core {@link JavaScriptStack}.
    216     */
    217    public static final String DEFAULT_STYLESHEET = "tapestry.default-stylesheet";
    218
    219    /**
    220     * The Asset path to the embedded copy of script.aculo.us packaged with Tapestry.
    221     *
    222     * @since 5.2.0
    223     */
    224    public static final String SCRIPTACULOUS = "tapestry.scriptaculous";
    225
    226    /**
    227     * The Asset path to the embedded datepicker.
    228     *
    229     * @since 5.2.0
    230     */
    231    public static final String DATEPICKER = "tapestry.datepicker";
    232
    233    /**
    234     * If "true", then JSON page initialization content is compressed; if "false"
    235     * then extra white space is added (pretty printing). Defaults to "true" in production mode.
    236     *
    237     * @since 5.2.0
    238     */
    239    public static final String COMPACT_JSON = "tapestry.compact-json";
    240
    241    /**
    242     * If "true" and {@link #PRODUCTION_MODE} is off, comments will be rendered before and after the rendering of any
    243     * component
    244     * allowing more visibility into which components rendered which markup. Defaults to "false". Component render
    245     * tracing may be
    246     * enabled per-request by the presence of a request parameter "t:component-trace" with a value of "true".
    247     *
    248     * @since 5.2.5
    249     */
    250    public static final String COMPONENT_RENDER_TRACING_ENABLED = "tapestry.component-render-tracing-enabled";
    251
    252    /**
    253     * The hostname that application should use when constructing an absolute URL. The default is "", i.e. an empty
    254     * string,
    255     * in which case system will use request.getServerName(). Not the same as environment variable HOSTNAME, but you can
    256     * also
    257     * contribute "$HOSTNAME" as the value to make it the same as the environment variable HOSTNAME.
    258     *
    259     * @since 5.3
    260     */
    261    public static final String HOSTNAME = "tapestry.hostname";
    262
    263    /**
    264     * The hostport that application should use when constructing an absolute URL. The default is "0", i.e. use the port
    265     * value from
    266     * the request.
    267     *
    268     * @since 5.3
    269     */
    270    public static final String HOSTPORT = "tapestry.hostport";
    271
    272    /**
    273     * The secure (https) hostport that application should use when constructing an absolute URL. The default is "0",
    274     * i.e. use
    275     * the value from the request.
    276     *
    277     * @since 5.3
    278     */
    279    public static final String HOSTPORT_SECURE = "tapestry.hostport-secure";
    280
    281    /**
    282     * If "true", then resources (individually or when aggregated into stacks) will be minimized via the
    283     * {@link ResourceMinimizer} service. If "false", then minification is disabled. Tracks production mode
    284     * (minification is normally disabled in development mode).
    285     *
    286     * Note that Tapestry's default implementation of {@link ResourceMinimizer} does nothing; minification is provided
    287     * by add-on libraries.
    288     *
    289     * @since 5.3
    290     */
    291    public static final String MINIFICATION_ENABLED = "tapestry.enable-minification";
    292
    293    /**
    294     * If "true" then at the end of each request the
    295     * {@link org.apache.tapestry5.services.SessionPersistedObjectAnalyzer} will be called on each session persisted
    296     * object that was accessed during the request.
    297     *
    298     * This is provided as a performance enhancement for servers that do not use clustered sessions.
    299     *
    300     * The default is {@code true}, to preserve 5.2 behavior. For non-clustered applications (the majority), this value should be
    301     * overridden to {@code false}. A future release of Tapestry may change the default.
    302     *
    303     * @since 5.3
    304     */
    305    public static final String CLUSTERED_SESSIONS = "tapestry.clustered-sessions";
    306
    307    /**
    308     * The name of a folder in which the Tapestry application executes. Prior to 5.3, a Tapestry application always responded to all
    309     * URLs in the context under the context root; by setting this to the name of a folder, the T5 URLs will be inside that folder only, and should
    310     * match a corresponding entry in the {@code web.xml} configuration file.  This is useful when running multiple servlets within the same web application (such as when migrating
    311     * from Tapestry 4 or some other framework, to Tapestry 5).
    312     * Effectively, if this symbol is set to a value, that folder name will be placed after the context path
    313     * (typically "/") and before the locale, page name, or other prefix.  For example, if this symbol is set to "app", the {@code web.xml <url-pattern>} should be set to {@code /app/*}, and Tapestry will
    314     * only be in invoked by the servlet container for requests inside the virtual {@code app} folder.
    315     *
    316     * This also affects the search for page templates (which are allowed within the web context). When set to a non-blank value, page templates are searched for in the folder, rather than in the root context.
    317     *
    318     * The default value is the empty string, which preserves Tapestry 5.2 behavior (and continues to be appropriate for most applications).
    319     *
    320     * Note that while Tapestry is case-insensitive, the servlet container is not, so the configured value must exactly match
    321     * the folder name inside the {@code <url-parameter>} value, including case.
    322     *
    323     * @since 5.3
    324     */
    325    public static final String APPLICATION_FOLDER = "tapestry.application-folder";
    326
    327    /**
    328     * Boolean value to indicate if every {@link  org.apache.tapestry5.Asset2} should be fully qualified or not.
    329     * Default to <code>false</code> meaning no Asset URL will be fully qualified.
    330     *
    331     * @since 5.3
    332     */
    333    public static final String ASSET_URL_FULL_QUALIFIED = "tapestry.asset-url-fully-qualified";
    334
    335    /**
    336     * Prefix to be used for all resource paths, used to recognize which requests are for assets. This value
    337     * is appended to the context path and the (optional {@linkplain #APPLICATION_FOLDER application folder}.
    338     * It may contain slashes, but should not begin or end with one.
    339     *
    340     * The default is "assets".
    341     */
    342    public static final String ASSET_PATH_PREFIX = "tapestry.asset-path-prefix";
    343
    344
    345    /**
    346     * Prefix used for all module resources. This may contain slashes, but should not being or end with one.
    347     * Tapestry will create two {@link org.apache.tapestry5.services.Dispatcher}s from this: one for normal
    348     * modules, the other for GZip compressed modules (by appending ".gz" to this value).
    349     *
    350     * The default is "modules".
    351     *
    352     * @since 5.4
    353     */
    354    public static final String MODULE_PATH_PREFIX = "tapestry.module-path-prefix";
    355
    356    /**
    357     * Identifies the context path of the application, as determined from {@link javax.servlet.ServletContext#getContextPath()}.
    358     * This is either a blank string or a string that starts with a slash but does not end with one.
    359     *
    360     * @since 5.4
    361     */
    362    public static final String CONTEXT_PATH = "tapestry.context-path";
    363
    364    /**
    365     * A passphrase used as the basis of hash-based message authentication (HMAC) for any object stream data stored on
    366     * the client.  The default phrase is the empty string, which will result in a logged runtime <em>error</em>.
    367     * You should configure this to a reasonable value (longer is better) and ensure that all servers in your cluster
    368     * share the same value (configuring this in code, rather than the command line, is preferred).
    369     *
    370     * @see org.apache.tapestry5.services.ClientDataEncoder
    371     * @since 5.3.6
    372     */
    373    public static final String HMAC_PASSPHRASE = "tapestry.hmac-passphrase";
    374
    375    /**
    376     * The root asset path for Twitter Bootstrap; if your application uses a modified version of Bootstrap,
    377     * you can override this symbol to have Tapestry automatically use your version. The value should be a path
    378     * to a folder (under "classpath:" or "context:") and should not include a trailing slash.
    379     *
    380     * @since 5.4
    381     */
    382    public static final String BOOTSTRAP_ROOT = "tapestry.bootstrap-root";
    383
    384    /**
    385     * Tapestry relies on an underlying client-side JavaScript infrastructure framework to handle DOM manipulation,
    386     * event handling, and Ajax requests. Through Tapestry 5.3, the foundation was
    387     * <a href="http://http://prototypejs.org/">Prototype</a>. In 5.4, support for
    388     * <a href="http://jquery.org/">jQuery</a> has been added, and it is possible to add others. This symbol defines a value that is used to select
    389     * a resource that is provided to the {@link org.apache.tapestry5.services.javascript.ModuleManager} service
    390     * as a {@link org.apache.tapestry5.services.javascript.JavaScriptModuleConfiguration} to provide a specific implementation
    391     * of the {@code t5/core/dom} module. Tapestry 5.4 directly supports "prototype" or "jquery".  To support
    392     * other foundation frameworks, override this symbol value and supply your own module configuration.
    393     *
    394     * In Tapestry 5.4, this defaults to "prototype" for compatibility with 5.3. This will likely change in
    395     * 5.5 to default to "jquery". At some point in the future, Prototype support will no longer be present.
    396     *
    397     * @since 5.4
    398     */
    399    public static final String JAVASCRIPT_INFRASTRUCTURE_PROVIDER = "tapestry.javascript-infrastructure-provider";
    400
    401    /**
    402     * If true (the default), then Tapestry will apply locking semantics around access to the {@link javax.servlet.http.HttpSession}.
    403     * Reading attribute names occurs with a shared read lock; getting or setting an attribute upgrades to an exclusive write lock.
    404     * This can tend to serialize threads when a number of simultaneous (Ajax) requests from the client arrive ... however,
    405     * many implementations of HttpSession are not thread safe, and often mutable objects are stored in the session and shared
    406     * between threads. Leaving this on the default will yield a more robust application; setting it to false may speed
    407     * up processing for more Ajax intensive applications (but care should then be given to ensuring that objects shared inside
    408     * the session are themselves immutable or thread-safe).
    409     *
    410     * @since 5.4
    411     */
    412    public static final String SESSION_LOCKING_ENABLED = "tapestry.session-locking-enabled";
    413
    414    /**
    415     * If true (the default), then Tapestry will automatically include the "core" stack in all
    416     * pages.
    417     *
    418     * @see <a href="https://issues.apache.org/jira/browse/TAP5-2169">TAP5-2169</a>
    419     * @since 5.4
    420     */
    421    public static final String INCLUDE_CORE_STACK = "tapestry.include-core-stack";
    422
    423    /**
    424     * Defines the CSS class that will be given to HTML element (usually a div) &lt;div&gt; generated by
    425     * the {@linkplain FormGroup} mixin and the
    426     * {@linkplain BeanEditForm} and {@linkplain BeanEditor}
    427     * components surrounding the label and the field. The default value is <code>form-group</code>.
    428     *
    429     * @see <a href="https://issues.apache.org/jira/browse/TAP5-2182">TAP5-2182</a>
    430     * @since 5.4
    431     */
    432    public static final String FORM_GROUP_WRAPPER_CSS_CLASS = "tapestry.form-group-wrapper-css-class";
    433
    434    /**
    435     * Defines the name of the HTML element that will surround the HTML form field generated by
    436     * the {@linkplain FormGroup} mixin and the {@linkplain BeanEditForm} and {@linkplain BeanEditor}.
    437     * If this symbol is null or an empty string, no element will be generated surrouding the
    438     * form field. The default value is the empty string (no wrapping).
    439     *
    440     * @see <a href="https://issues.apache.org/jira/browse/TAP5-2182">TAP5-2182</a>
    441     * @see #FORM_GROUP_FORM_FIELD_WRAPPER_ELEMENT_CSS_CLASS
    442     * @since 5.4
    443     */
    444    public static final String FORM_GROUP_FORM_FIELD_WRAPPER_ELEMENT_NAME = "tapestry.form-group-form-field-wrapper-element-name";
    445
    446    /**
    447     * Defines the CSS class of the HTML element generated by
    448     * the {@linkplain FormGroup} mixin and the {@linkplain BeanEditForm} and {@linkplain BeanEditor}.
    449     * when {@linkplain #FORM_GROUP_FORM_FIELD_WRAPPER_ELEMENT_NAME} is not set to null or the empty string.
    450     * The default value is the empty string (no CSS class added).
    451     *
    452     * @see <a href="https://issues.apache.org/jira/browse/TAP5-2182">TAP5-2182</a>
    453     * @since 5.4
    454     */
    455    public static final String FORM_GROUP_FORM_FIELD_WRAPPER_ELEMENT_CSS_CLASS = "tapestry.form-group-form-field-wrapper-element-css-class";
    456
    457    /**
    458     * Defines the CSS class that will be given to &lt;label&gt; element generated by
    459     * the {@linkplain FormGroup} mixin and the
    460     * {@linkplain BeanEditForm} and {@linkplain BeanEditor}
    461     * components. The default value is <code>control-label</code>.
    462     *
    463     * @see <a href="https://issues.apache.org/jira/browse/TAP5-2182">TAP5-2182</a>
    464     * @since 5.4
    465     */
    466    public static final String FORM_GROUP_LABEL_CSS_CLASS = "tapestry.form-group-label-css-class";
    467
    468    /**
    469     * Defines the CSS class that will be given to form field components which are
    470     * {@linkplain AbstractField} subclasses. The default value is <code>form-control</code>.
    471     *
    472     * @see <a href="https://issues.apache.org/jira/browse/TAP5-2182">TAP5-2182</a>
    473     * @since 5.4
    474     */
    475    public static final String FORM_FIELD_CSS_CLASS = "tapestry.form-field-css-class";
    476
    477    /**
    478     * Defines whether {@link java.text.DateFormat} instances created by Tapestry should be
    479     * lenient or not by default. The default value is <code>false</code>.
    480     *
    481     * @since 5.4
    482     */
    483    public static final String LENIENT_DATE_FORMAT = "tapestry.lenient-date-format";
    484
    485    /**
    486     * The directory to which exception report files should be written. The default is appropriate
    487     * for development: {@code build/exceptions}, and should be changed for production.
    488     *
    489     * @see org.apache.tapestry5.services.ExceptionReporter
    490     * @since 5.4
    491     */
    492
    493    public static final String EXCEPTION_REPORTS_DIR = "tapestry.exception-reports-dir";
    494
    495    /**
    496     * Defines whether {@link org.apache.tapestry5.internal.services.assets.CSSURLRewriter} will throw an exception when a CSS file
    497     * references an URL which doesn't exist. The default value is <code>false</code>.
    498     *
    499     * @since 5.4
    500     */
    501    public static final String STRICT_CSS_URL_REWRITING = "tapestry.strict-css-url-rewriting";
    502
    503    /**
    504     * When an asset (typically, a JavaScript module) is streamed without an explicit expiration header, then
    505     * this value is sent as the {@code Cache-Control} header; the default is "max-age=60, must-revalidate". Setting
    506     * max-age to a value above zero significantly reduces the number of client requests for module content, as client
    507     * browsers will then cache previously downloaded versions. For normal assets, which are immutable, and fingerprinted with
    508     * a content hash, there is no need to set max age, and instead, a far-future expiration date is provided.
    509     *
    510     * @since 5.4
    511     */
    512    public static final String OMIT_EXPIRATION_CACHE_CONTROL_HEADER = "tapestry.omit-expiration-cache-control-header";
    513
    514    /**
    515     * Defines whether HTML5 features should be used. Value used in the default implementation of
    516     * {@link Html5Support#isHtml5SupportEnabled()}. Default value: <code>false</code>.
    517     *
    518     * @see Html5Support#isHtml5SupportEnabled()
    519     * @since 5.4
    520     */
    521    public static final String ENABLE_HTML5_SUPPORT = "tapestry.enable-html5-support";
    522
    523    /**
    524     * A general switch for restrictive environments, such as Google App Engine, which forbid some useful operations,
    525     * such as creating files or directories. Defaults to false.
    526     *
    527     * @since 5.4
    528     */
    529    public static final String RESTRICTIVE_ENVIRONMENT = "tapestry.restrictive-environment";
    530
    531    /**
    532     * If true, then when a page includes any JavaScript, a {@code script} block is added to insert
    533     * a pageloader mask into the page; the pageloader mask ensure that the user can't interact with the page
    534     * until after the page is fully initialized.
    535     *
    536     * @since 5.4
    537     */
    538    public static final String ENABLE_PAGELOADING_MASK = "tapestry.enable-pageloading-mask";
    539
    540    /**
    541     * Controls in what environment page preloading should occur. By default, preloading only occurs
    542     * in production.
    543     *
    544     * @see org.apache.tapestry5.services.pageload.PagePreloader
    545     * @see org.apache.tapestry5.services.pageload.PreloaderMode
    546     * @since 5.4
    547     */
    548    public static final String PRELOADER_MODE = "tapestry.page-preload-mode";
    549}