Class LinkTool

java.lang.Object
org.apache.velocity.tools.generic.SafeConfig
org.apache.velocity.tools.generic.LinkTool
org.apache.velocity.tools.view.LinkTool
All Implemented Interfaces:
Serializable, Cloneable
public class LinkTool extends org.apache.velocity.tools.generic.LinkTool

The LinkTool provides many methods to work with URIs and can help you:

  • construct full URIs (absolute or relative)
  • encode session ID into a URI
  • retrieve server, port and path info for the current request
  • reconstruct or alter the current request URI
  • and more..

The LinkTool is somewhat special in that nearly all public methods return a new instance of LinkTool. This facilitates greatly the repeated use of the LinkTool in Velocity and leads to an elegant syntax.

Template example(s):


  #set( $base = $link.path('MyPage.vm').anchor('view') )
  <a href="$base.param('select','this')">this</a>
  <a href="$base.param('select','that')">that</a>

Toolbox configuration:
<tools>
  <toolbox scope="request">
    <tool class="org.apache.velocity.tools.view.LinkTool"
             forceRelative="true" includeRequestParams="true"/>
  </toolbox>
</tools>

This tool may only be used in the request scope.

Since:
VelocityTools 2.0
Version:
$Id$
Author:
Gabe Sidler, Nathan Bubna, Chris Schultz
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final String
    INCLUDE_REQUEST_PARAMS_KEY
     
    protected boolean
    includeRequestParams
     
    protected javax.servlet.http.HttpServletRequest
    request
     
    protected javax.servlet.http.HttpServletResponse
    response
     

    Fields inherited from class org.apache.velocity.tools.generic.LinkTool

    APPEND_PARAMS_KEY, appendParams, charset, CHARSET_KEY, DEFAULT_CHARSET, DEFAULT_SCHEME, FORCE_RELATIVE_KEY, forceRelative, fragment, FRAGMENT_KEY, host, HOST_KEY, HTML_QUERY_DELIMITER, opaque, path, PATH_KEY, port, PORT_KEY, query, QUERY_KEY, queryDelim, scheme, SCHEME_KEY, SECURE_SCHEME, self, URI_KEY, user, USER_KEY, XHTML_MODE_KEY, XHTML_QUERY_DELIMITER

    Fields inherited from class org.apache.velocity.tools.generic.SafeConfig

    LOCK_CONFIG_KEY, log, LOGGER_NAME_KEY, SAFE_MODE_KEY, USE_CLASS_LOGGER_KEY

  • Constructor Summary

    Constructors
    Constructor
    Description
    LinkTool()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    LinkTool
    addMissingRequestParams(Object... ignoreThese)
    Adds all of the current request's parameters to this link's "query data" except for those whose keys match any of the specified strings or already have a value set for them in the current instance.
    LinkTool
    addRequestParams(Object... butOnlyThese)
    Adds the specified parameters (if they exist) from the current request to the query data of a copy of this instance.
    LinkTool
    addRequestParamsExcept(Object... ignoreThese)
    Adds all of the current request's parameters to this link's "query data" except for those whose keys match any of the specified strings.
    protected void
    configure(org.apache.velocity.tools.generic.ValueParser props)
     
    String
    getContextPath()
    Initially, this returns the context path that addresses this web application, e.g.
    String
    getContextURL()
    Returns a URL that addresses the web application.
    String
    getRequestPath()
    Initially, this retrieves the path for the current request regardless of whether this is a direct request or an include by the RequestDispatcher.
    protected boolean
    isPathChanged()
     
    protected void
    setFromRequest(javax.servlet.http.HttpServletRequest request)
     
    void
    setIncludeRequestParams(boolean includeRequestParams)
    Controls whether or not this tool starts off with all parameters from the last request automatically.
    String
    toString()
    Overrides to use response.encodeURL to get session id into URL if sessions are used but cookies are not supported.

    Methods inherited from class org.apache.velocity.tools.generic.LinkTool

    absolute, absolute, anchor, append, append, appendAsArray, appendPath, appendQuery, combinePath, combineQuery, createURI, decode, decodeQueryPercents, directory, duplicate, duplicate, encode, equals, getAnchor, getAppendParams, getBaseRef, getCharacterEncoding, getDirectory, getFile, getHost, getParams, getPath, getPort, getQuery, getRoot, getScheme, getSelf, getUri, getUser, handleParamsBoolean, hashCode, host, insecure, isAbsolute, isOpaque, isRelative, isSecure, isXHTML, normalizeQuery, param, params, parseQuery, parseQuery, path, port, query, relative, relative, remove, removeParam, root, scheme, secure, set, setAppendParams, setCharacterEncoding, setForceRelative, setFragment, setFromURI, setHost, setParam, setParams, setPath, setPort, setQuery, setScheme, setUserInfo, setXHTML, toQuery, toQuery, toURI, uri, user

    Methods inherited from class org.apache.velocity.tools.generic.SafeConfig

    configure, getLog, initLogger, isConfigLocked, isSafeMode, setLockConfig, setSafeMode

    Methods inherited from class Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  • Field Details

    • INCLUDE_REQUEST_PARAMS_KEY

      public static final String INCLUDE_REQUEST_PARAMS_KEY
      See Also:

    • request

      protected javax.servlet.http.HttpServletRequest request

    • response

      protected javax.servlet.http.HttpServletResponse response

    • includeRequestParams

      protected boolean includeRequestParams

  • Constructor Details

    • LinkTool

      public LinkTool()

  • Method Details

    • configure

      protected void configure(org.apache.velocity.tools.generic.ValueParser props)
      Overrides:
      configure in class org.apache.velocity.tools.generic.LinkTool

    • setFromRequest

      protected void setFromRequest(javax.servlet.http.HttpServletRequest request)

    • setIncludeRequestParams

      public void setIncludeRequestParams(boolean includeRequestParams)

      Controls whether or not this tool starts off with all parameters from the last request automatically. Default is false.

      Parameters:
      includeRequestParams - whether or not to keep current request params

    • addRequestParams

      public LinkTool addRequestParams(Object... butOnlyThese)
      Adds the specified parameters (if they exist) from the current request to the query data of a copy of this instance. If no parameters are specified, then all of the current request's parameters will be added.
      Parameters:
      butOnlyThese - curent request parameters to keep
      Returns:
      A LinkTool object with the specified parameters from the current request added to it or all the params if none specified.

    • addRequestParamsExcept

      public LinkTool addRequestParamsExcept(Object... ignoreThese)
      Adds all of the current request's parameters to this link's "query data" except for those whose keys match any of the specified strings.
      Parameters:
      ignoreThese - curent request parameters to ignore
      Returns:
      A LinkTool object with all of the current request's parameters added to it, except those specified.

    • addMissingRequestParams

      public LinkTool addMissingRequestParams(Object... ignoreThese)
      Adds all of the current request's parameters to this link's "query data" except for those whose keys match any of the specified strings or already have a value set for them in the current instance.
      Parameters:
      ignoreThese - curent request parameters to ignore
      Returns:
      A LinkTool object with all of the current request's parameters added to it, except those specified or those that already have values.

    • isPathChanged

      protected boolean isPathChanged()

    • getContextPath

      public String getContextPath()

      Initially, this returns the context path that addresses this web application, e.g. /myapp. This string starts with a "/" but does not end with a "/". If the path has been changed (e.g. via a call to LinkTool.path(Object)), then this will simply be the first "directory" in the path (i.e. everything from the start up to the second backslash).

      Overrides:
      getContextPath in class org.apache.velocity.tools.generic.LinkTool
      Returns:
      context path
      See Also:
      • LinkTool.relative(Object)

    • getRequestPath

      public String getRequestPath()

      Initially, this retrieves the path for the current request regardless of whether this is a direct request or an include by the RequestDispatcher. This string should always start with a "/". If the path has been changed (e.g. via a call to LinkTool.path(Object)), then this will simply be everything in the path after the getContextPath() (i.e. the second "/" in the path and everything after).

      Returns:
      request path

    • getContextURL

      public String getContextURL()

      Returns a URL that addresses the web application. (e.g. http://myserver.net/myapp/. This essentially just replaces the full path with the getContextPath() and removes the anchor and query data.

      Returns:
      context URL

    • toString

      public String toString()
      Overrides to use response.encodeURL to get session id into URL if sessions are used but cookies are not supported.
      Overrides:
      toString in class org.apache.velocity.tools.generic.LinkTool
      Returns:
      final string representation