Package org.apache.struts.taglib

Class TagUtils

java.lang.Object
org.apache.struts.taglib.TagUtils
public class TagUtils extends Object
Provides helper methods for JSP tags.
Since:
Struts 1.2
Version:
$Rev$

  • Field Details

    • XHTML_1_0

      public static final BigDecimal XHTML_1_0
      Constant for XHTML 1.0 conformance.
      Since:
      Struts 1.4

    • XHTML_1_1

      public static final BigDecimal XHTML_1_1
      Constant for XHTML 1.1 conformance.
      Since:
      Struts 1.4

    • XHTML_2_0

      public static final BigDecimal XHTML_2_0
      Constant for XHTML 2.0 conformance.
      Since:
      Struts 1.4

    • XHTML_5_0

      public static final BigDecimal XHTML_5_0
      Constant for XHTML 5.0 conformance.
      Since:
      Struts 1.4

  • Constructor Details

    • TagUtils

      protected TagUtils()
      Constructor for TagUtils.

  • Method Details

    • getInstance

      public static TagUtils getInstance()
      Returns the Singleton instance of TagUtils.

    • setInstance

      public static void setInstance(TagUtils instance)
      Set the instance. This blatantly violates the Singleton pattern, but then some say Singletons are an anti-pattern.
      Parameters:
      instance - The instance to set.
      Since:
      1.3.5 Changed to non-final and added setInstance() so TagUtils may be overridden, use at your own risk (you've been warned!!)

    • computeParameters

      public Map<String,Object> computeParameters(PageContext pageContext, String paramId, String paramName, String paramProperty, String paramScope, String name, String property, String scope, boolean transaction) throws JspException
      Compute a set of query parameters that will be dynamically added to a generated URL. The returned Map is keyed by parameter name, and the values are either null (no value specified), a String (single value specified), or a String[] array (multiple values specified). Parameter names correspond to the corresponding attributes of the <html:link> tag. If no query parameters are identified, return null.
      Parameters:
      pageContext - PageContext we are operating in
      paramId - Single-value request parameter name (if any)
      paramName - Bean containing single-value parameter value
      paramProperty - Property (of bean named by paramName containing single-value parameter value
      paramScope - Scope containing bean named by paramName
      name - Bean containing multi-value parameters Map (if any)
      property - Property (of bean named by name containing multi-value parameters Map
      scope - Scope containing bean named by name
      transaction - Should we add our transaction control token?
      Returns:
      Map of query parameters
      Throws:
      JspException - if we cannot look up the required beans
      JspException - if a class cast exception occurs on a looked-up bean or property

    • computeURL

      public String computeURL(PageContext pageContext, String forward, String href, String page, String action, String module, Map<String,?> params, String anchor, boolean redirect) throws MalformedURLException
      Throws:
      MalformedURLException

    • computeURLWithCharEncoding

      public String computeURLWithCharEncoding(PageContext pageContext, String forward, String href, String page, String action, String module, Map<String,?> params, String anchor, boolean redirect, boolean useLocalEncoding) throws MalformedURLException
      Compute a hyperlink URL based on the forward, href, action or page parameter that is not null. The returned URL will have already been passed to response.encodeURL() for adding a session identifier.
      Parameters:
      pageContext - PageContext for the tag making this call
      forward - Logical forward name for which to look up the context-relative URI (if specified)
      href - URL to be utilized unmodified (if specified)
      page - Module-relative page for which a URL should be created (if specified)
      action - Logical action name for which to look up the context-relative URI (if specified)
      params - Map of parameters to be dynamically included (if any)
      anchor - Anchor to be dynamically included (if any)
      redirect - Is this URL for a response.sendRedirect()?
      Returns:
      URL with session identifier
      Throws:
      MalformedURLException - if a URL cannot be created for the specified parameters

    • computeURL

      public String computeURL(PageContext pageContext, String forward, String href, String page, String action, String module, Map<String,?> params, String anchor, boolean redirect, boolean encodeSeparator) throws MalformedURLException
      Throws:
      MalformedURLException

    • computeURLWithCharEncoding

      public String computeURLWithCharEncoding(PageContext pageContext, String forward, String href, String page, String action, String module, Map<String,?> params, String anchor, boolean redirect, boolean encodeSeparator, boolean useLocalEncoding) throws MalformedURLException
      Compute a hyperlink URL based on the forward, href, action or page parameter that is not null. The returned URL will have already been passed to response.encodeURL() for adding a session identifier.
      Parameters:
      pageContext - PageContext for the tag making this call
      forward - Logical forward name for which to look up the context-relative URI (if specified)
      href - URL to be utilized unmodified (if specified)
      page - Module-relative page for which a URL should be created (if specified)
      action - Logical action name for which to look up the context-relative URI (if specified)
      params - Map of parameters to be dynamically included (if any)
      anchor - Anchor to be dynamically included (if any)
      redirect - Is this URL for a response.sendRedirect()?
      encodeSeparator - This is only checked if redirect is set to false (never encoded for a redirect). If true, query string parameter separators are encoded as >amp;, else & is used.
      useLocalEncoding - If set to true, urlencoding is done on the bytes of character encoding from ServletResponse#getCharacterEncoding. Use UTF-8 otherwise.
      Returns:
      URL with session identifier
      Throws:
      MalformedURLException - if a URL cannot be created for the specified parameters

    • encodeURL

      public String encodeURL(String url)
      URLencodes a string assuming the character encoding is UTF-8.
      Parameters:
      url -
      Returns:
      String The encoded url in UTF-8

    • encodeURL

      public String encodeURL(String url, String enc)
      Use the new URLEncoder.encode() method from Java 1.4 if available, else use the old deprecated version. This method uses reflection to find the appropriate method; if the reflection operations throw exceptions, this will return the url encoded with the old URLEncoder.encode() method.
      Parameters:
      enc - The character encoding the urlencode is performed on.
      Returns:
      String The encoded url.

    • filter

      public String filter(String value)
      Filter the specified string for characters that are sensitive to HTML interpreters, returning the string with these characters replaced by the corresponding character entities.
      Parameters:
      value - The string to be filtered and returned

    • getActionMappingName

      public String getActionMappingName(String action)
      Return the form action converted into an action mapping path. The value of the action property is manipulated as follows in computing the name of the requested mapping:
      • Any filename extension is removed (on the theory that extension mapping is being used to select the controller servlet).
      • If the resulting value does not start with a slash, then a slash is prepended.

    • getActionMappingURL

      public String getActionMappingURL(String action, PageContext pageContext)
      Return the form action converted into a server-relative URL.

    • getActionMappingURL

      public String getActionMappingURL(String action, String module, PageContext pageContext, boolean contextRelative)
      Return the form action converted into a server-relative URL.

    • getActionMessages

      public ActionMessages getActionMessages(PageContext pageContext, String paramName) throws JspException
      Retrieves the value from request scope and if it isn't already an ActionMessages, some classes are converted to one.
      Parameters:
      pageContext - The PageContext for the current page
      paramName - Key for parameter value
      Returns:
      ActionErrors in page context.
      Throws:
      JspException

    • getModuleConfig

      public ModuleConfig getModuleConfig(PageContext pageContext)
      Return the default ModuleConfig object if it exists, null if otherwise.
      Parameters:
      pageContext - The page context.
      Returns:
      the ModuleConfig object

    • getModuleConfig

      public ModuleConfig getModuleConfig(String module, PageContext pageContext)
      Return the specified ModuleConfig object for the given prefix if it exists, otherwise a NullPointerException will be thrown.
      Parameters:
      module - The module prefix
      pageContext - The page context.
      Returns:
      the ModuleConfig object
      Throws:
      NullPointerException - Thrown when module cannot be found

    • getScope

      public int getScope(String scopeName) throws JspException
      Converts the scope name into its corresponding PageContext constant value.
      Parameters:
      scopeName - Can be "page", "request", "session", or "application" in any case.
      Returns:
      The constant representing the scope (ie. PageContext.REQUEST_SCOPE).
      Throws:
      JspException - if the scopeName is not a valid name.

    • getUserLocale

      public Locale getUserLocale(PageContext pageContext, String locale)
      Look up and return current user locale, based on the specified parameters.
      Parameters:
      pageContext - The PageContext associated with this request
      locale - Name of the session attribute for our user's Locale. If this is null, the default locale key is used for the lookup.
      Returns:
      current user locale

    • isXhtml

      public boolean isXhtml(PageContext pageContext)
      Returns true if the custom tags are in XHTML mode.

    • lookup

      public Object lookup(PageContext pageContext, String name, String scopeName) throws JspException
      Locate and return the specified bean, from an optionally specified scope, in the specified page context. If no such bean is found, return null instead. If an exception is thrown, it will have already been saved via a call to saveException().
      Parameters:
      pageContext - Page context to be searched
      name - Name of the bean to be retrieved
      scopeName - Scope to be searched (page, request, session, application) or null to use findAttribute() instead
      Returns:
      JavaBean in the specified page context
      Throws:
      JspException - if an invalid scope name is requested

    • lookup

      public Object lookup(PageContext pageContext, String name, String property, String scope) throws JspException
      Locate and return the specified property of the specified bean, from an optionally specified scope, in the specified page context. If an exception is thrown, it will have already been saved via a call to saveException().
      Parameters:
      pageContext - Page context to be searched
      name - Name of the bean to be retrieved
      property - Name of the property to be retrieved, or null to retrieve the bean itself
      scope - Scope to be searched (page, request, session, application) or null to use findAttribute() instead
      Returns:
      property of specified JavaBean
      Throws:
      JspException - if an invalid scope name is requested
      JspException - if the specified bean is not found
      JspException - if accessing this property causes an IllegalAccessException, IllegalArgumentException, InvocationTargetException, or NoSuchMethodException

    • message

      public String message(PageContext pageContext, String bundle, String locale, String key) throws JspException
      Look up and return a message string, based on the specified parameters.
      Parameters:
      pageContext - The PageContext associated with this request
      bundle - Name of the servlet context attribute for our message resources bundle
      locale - Name of the session attribute for our user's Locale
      key - Message key to be looked up and returned
      Returns:
      message string
      Throws:
      JspException - if a lookup error occurs (will have been saved in the request already)

    • message

      public String message(PageContext pageContext, String bundle, String locale, String key, Object[] args) throws JspException
      Look up and return a message string, based on the specified parameters.
      Parameters:
      pageContext - The PageContext associated with this request
      bundle - Name of the servlet context attribute for our message resources bundle
      locale - Name of the session attribute for our user's Locale
      key - Message key to be looked up and returned
      args - Replacement parameters for this message
      Returns:
      message string
      Throws:
      JspException - if a lookup error occurs (will have been saved in the request already)

    • pageURL

      public String pageURL(HttpServletRequest request, String page, ModuleConfig moduleConfig)

      Return the context-relative URL that corresponds to the specified page attribute value, calculated based on the pagePattern property of the current module's ModuleConfig.

      Parameters:
      request - The servlet request we are processing
      page - The module-relative URL to be substituted in to the pagePattern pattern for the current module (MUST start with a slash)
      Returns:
      context-relative URL

    • present

      public boolean present(PageContext pageContext, String bundle, String locale, String key) throws JspException
      Return true if a message string for the specified message key is present for the specified Locale and bundle.
      Parameters:
      pageContext - The PageContext associated with this request
      bundle - Name of the servlet context attribute for our message resources bundle
      locale - Name of the session attribute for our user's Locale
      key - Message key to be looked up and returned
      Returns:
      true if a message string for message key exists
      Throws:
      JspException - if a lookup error occurs (will have been saved in the request already)

    • retrieveMessageResources

      public MessageResources retrieveMessageResources(PageContext pageContext, String bundle, boolean checkPageScope) throws JspException
      Returns the appropriate MessageResources object for the current module and the given bundle.
      Parameters:
      pageContext - Search the context's scopes for the resources.
      bundle - The bundle name to look for. If this is null, the default bundle name is used.
      checkPageScope - Whether to check page scope
      Returns:
      MessageResources The bundle's resources stored in some scope.
      Throws:
      JspException - if the MessageResources object could not be found.

    • saveException

      public void saveException(PageContext pageContext, Throwable exception)
      Save the specified exception as a request attribute for later use.
      Parameters:
      pageContext - The PageContext for the current page
      exception - The exception to be saved

    • write

      public void write(PageContext pageContext, String text) throws JspException
      Write the specified text as the response to the writer associated with this page. WARNING - If you are writing body content from the doAfterBody() method of a custom tag class that implements BodyTag, you should be calling writePrevious() instead.
      Parameters:
      pageContext - The PageContext object for this page
      text - The text to be written
      Throws:
      JspException - if an input/output error occurs (already saved)

    • writePrevious

      public void writePrevious(PageContext pageContext, String text) throws JspException
      Write the specified text as the response to the writer associated with the body content for the tag within which we are currently nested.
      Parameters:
      pageContext - The PageContext object for this page
      text - The text to be written
      Throws:
      JspException - if an input/output error occurs (already saved)