initial sketch of trackback-handling servlet

etc/web.xml

@@ -97,7 +97,7 @@
 
   <servlet>
     <servlet-name>PostShortcut</servlet-name>
-    <description>Redirects the user to a comunity, conference, topic, or message.</description>
+    <description>Redirects the user to a community, conference, topic, or message.</description>
     <servlet-class>com.silverwrist.venice.ui.conf.PostShortcutServlet</servlet-class>
   </servlet>
 
@@ -125,6 +125,12 @@
     <servlet-class>com.silverwrist.venice.ui.rpc.XmlRpcServlet</servlet-class>
   </servlet>
 
+  <servlet>
+    <servlet-name>Trackback</servlet-name>
+    <description>Handles trackback requests.</description>
+    <servlet-class>com.silverwrist.venice.ui.conf.TrackbackServlet</servlet-class>
+  </servlet>
+
   <!-- Servlet mappings -->
 
   <servlet-mapping>
@@ -192,6 +198,11 @@
     <url-pattern>/RPC2</url-pattern>
   </servlet-mapping>
 
+  <servlet-mapping>
+    <servlet-name>Trackback</servlet-name>
+    <url-pattern>/trackback/*</url-pattern>
+  </servlet-mapping>
+
   <!-- Global parameters for the HTTP session -->
   <session-config>
     <session-timeout>60</session-timeout>    <!-- 1 hour -->

src/com/silverwrist/venice/db/PostLinkDecoder.java

@@ -9,9 +9,9 @@
  * 
  * The Original Code is the Venice Web Community System.
  * 
- * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@ricochet.com>,
  * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
- * Copyright (C) 2001-02 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * Copyright (C) 2001-2004 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
  * 
  * Contributor(s): 
  */

src/com/silverwrist/venice/ui/RequestInput.java

@@ -38,14 +38,14 @@ public interface RequestInput extends ServiceProvider
   public static final String LEFT_MENU_SESSION_ATTR = "LeftMenu";
 
   /**
-   * Returns a <CODE>String</CODE> containing the real path for a given virtual path. For example,
+   * Returns a {@link java.lang.String String} containing the real path for a given virtual path. For example,
    * the virtual path &quot;/index.html&quot; has a real path of whatever file on the server's filesystem
-   * would be served by a request for &quot;/index.html&quot;.<P>
+   * would be served by a request for &quot;/index.html&quot;.<p>
-   * This method returns <CODE>null</CODE> if the virtual path cannot be translated to a real path for
+   * This method returns <code>null</code> if the virtual path cannot be translated to a real path for
    * any reason.
    *
-   * @param s A <CODE>String</CODE> specifying a virtual path.
+   * @param s A <code>String</code> specifying a virtual path.
-   * @return A <CODE>String</CODE> specifying the real path, or <CODE>null</CODE> if the translation cannot
+   * @return A <code>String</code> specifying the real path, or <code>null</code> if the translation cannot
    *         be performed.
    */
   public String mapPath(String s);
@@ -55,8 +55,8 @@ public interface RequestInput extends ServiceProvider
    * context under which Venice is installed. The context path always comes first in a request URI. The
    * path starts with a &quot;/&quot; character but does not end with a &quot;/&quot; character.
    *
-   * @return A <CODE>String</CODE> specifying the portion of the request URI that indicates the context
+   * @return A {@link java.lang.String String} specifying the portion of the request URI that indicates the
-   * of the request.
+   *         context of the request.
    */
   public String getContextPath();
 
@@ -64,28 +64,28 @@ public interface RequestInput extends ServiceProvider
    * Returns the part of this request's URI that calls the servlet. This includes either the servlet name
    * or a path to the servlet, but does not include any extra path information or a query string.
    *
-   * @return A <CODE>String</CODE> containing the name or path of the servlet being called, as specified
+   * @return A {@link java.lang.String String} containing the name or path of the servlet being called, as
-   *         in the request URI.
+   *         specified in the request URI.
    */
   public String getServletPath();
 
   /**
    * Returns any extra path information associated with the URI the client sent when it made this request.
    * The extra path information follows the servlet path but precedes the query string. This method
-   * returns <CODE>null</CODE> if there was no extra path information.  In Venice, the path information is
+   * returns <code>null</code> if there was no extra path information.  In Venice, the path information is
    * used to specify parameters in certain servlets.
    *
-   * @return A <CODE>String</CODE> specifying extra path information that comes after the servlet path
+   * @return A {@link java.lang.String String} specifying extra path information that comes after the servlet path
-   *         but before the query string in the request URI; or <CODE>null</CODE> if the URI does not
+   *         but before the query string in the request URI; or <code>null</code> if the URI does not
    *         have any extra path information.
    */
   public String getPathInfo();
 
   /**
    * Returns the query string that is contained in the request URI after the path. This method returns
-   * <CODE>null</CODE> if the URI does not have a query string.
+   * <code>null</code> if the URI does not have a query string.
    *
-   * @return A <CODE>String</CODE> containing the query string or <CODE>null</CODE> if the URI contains
+   * @return A {@link java.lang.String String} containing the query string or <code>null</code> if the URI contains
    *         no query string.
    */
   public String getQueryString();
@@ -93,20 +93,20 @@ public interface RequestInput extends ServiceProvider
   /**
    * Returns the name of the HTTP method with which this request was made, for example, GET, POST, or PUT.
    *
-   * @return A <CODE>String</CODE> specifying the name of the method with which this request was made.
+   * @return A {@link java.lang.String String} specifying the name of the method with which this request was made.
    */
   public String getVerb();
 
   /**
    * Returns the Internet Protocol (IP) address of the client that sent the request.
    *
-   * @return A <CODE>String</CODE> containing the IP address of the client that sent the request.
+   * @return A {@link java.lang.String String} containing the IP address of the client that sent the request.
    */
   public String getSourceAddress();
 
   /**
-   * Returns <CODE>true</CODE> if the request parameter with the specified name is defined,
+   * Returns <code>true</code> if the request parameter with the specified name is defined,
-   * <CODE>false</CODE> if not.  For standard Venice requests, parameters are contained in the
+   * <code>false</code> if not.  For standard Venice requests, parameters are contained in the
    * query string or posted form data.
    *
    * @param name Parameter name to be checked.
@@ -115,117 +115,120 @@ public interface RequestInput extends ServiceProvider
   public boolean hasParameter(String name);
 
   /**
-   * Returns the value of a request parameter as a <CODE>String</CODE>, or <CODE>null</CODE> if the
+   * Returns the value of a request parameter as a {@link java.lang.String String}, or <code>null</code> if the
    * parameter does not exist. For standard Venice requests, parameters are contained in the query
-   * string or posted form data.<P>
+   * string or posted form data.<p>
    * You should only use this method when you are sure the parameter has only one value. If the parameter
-   * might have more than one value, use {@link #getParameterValues(java.lang.String)}.<P>
+   * might have more than one value, use {@link #getParameterValues(java.lang.String)}.<p>
    * If you use this method with a multivalued parameter, the value returned is equal to the first value
-   * in the array returned by <CODE>getParameterValues</CODE>.
+   * in the array returned by <code>getParameterValues</code>.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the parameter.
+   * @param name A <code>String</code> specifying the name of the parameter.
-   * @return A <CODE>String</CODE> representing the single value of the parameter.
+   * @return A <code>String</code> representing the single value of the parameter.
    * @see #getParameterValues(java.lang.String)
    */
   public String getParameter(String name);
 
   /**
-   * Returns the value of a request parameter as a <CODE>int</CODE>, or a specified default value if
+   * Returns the value of a request parameter as a <code>int</code>, or a specified default value if
    * the parameter does not exist. For standard Venice requests, parameters are contained in the query
-   * string or posted form data.<P>
+   * string or posted form data.<p>
    * If you use this method with a multivalued parameter, the value returned is equal to the
-   * <CODE>int</CODE> equivalent of the first value in the array returned by <CODE>getParameterValues</CODE>.
+   * <code>int</code> equivalent of the first value in the array returned by
+   * {@link #getParameterValues(java.lang.String)}.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the parameter.
+   * @param name A {@link java.lang.String String} specifying the name of the parameter.
    * @param default_value The default value to use for the parameter if the specified parameter does not exist.
-   * @return An <CODE>int</CODE> representing the single value of the parameter.
+   * @return An <code>int</code> representing the single value of the parameter.
    */
   public int getParameterInt(String name, int default_value);
 
   /**
-   * Returns the value of a request parameter as a <CODE>short</CODE>, or a specified default value if
+   * Returns the value of a request parameter as a <code>short</code>, or a specified default value if
    * the parameter does not exist. For standard Venice requests, parameters are contained in the query
-   * string or posted form data.<P>
+   * string or posted form data.<p>
    * If you use this method with a multivalued parameter, the value returned is equal to the
-   * <CODE>short</CODE> equivalent of the first value in the array returned by <CODE>getParameterValues</CODE>.
+   * <code>short</code> equivalent of the first value in the array returned by
+   * {@link #getParameterValues(java.lang.String)}.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the parameter.
+   * @param name A {@link java.lang.String String} specifying the name of the parameter.
    * @param default_value The default value to use for the parameter if the specified parameter does not exist.
-   * @return A <CODE>short</CODE> representing the single value of the parameter.
+   * @return A <code>short</code> representing the single value of the parameter.
    */
   public short getParameterShort(String name, short default_value);
 
   /**
-   * Returns the value of a request parameter as a <CODE>long</CODE>, or a specified default value if
+   * Returns the value of a request parameter as a <code>long</code>, or a specified default value if
    * the parameter does not exist. For standard Venice requests, parameters are contained in the query
-   * string or posted form data.<P>
+   * string or posted form data.<p>
    * If you use this method with a multivalued parameter, the value returned is equal to the
-   * <CODE>long</CODE> equivalent of the first value in the array returned by <CODE>getParameterValues</CODE>.
+   * <code>long</code> equivalent of the first value in the array returned by
+   * {@link #getParameterValues(java.lang.String)}.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the parameter.
+   * @param name A {@link java.lang.String String} specifying the name of the parameter.
    * @param default_value The default value to use for the parameter if the specified parameter does not exist.
-   * @return A <CODE>long</CODE> representing the single value of the parameter.
+   * @return A <code>long</code> representing the single value of the parameter.
    */
   public long getParameterLong(String name, long default_value);
 
   /**
-   * Returns an <CODE>Enumeration</CODE> of <CODE>String</CODE> objects containing the names of the
+   * Returns an {@link java.util.Enumeration Enumeration} of {@link java.lang.String String} objects containing
-   * parameters contained in this request. If the request has no parameters, the method returns an empty
+   * the names of the parameters contained in this request. If the request has no parameters, the method returns
-   * <CODE>Enumeration.</CODE>
+   * an empty <code>Enumeration.</code>
    *
-   * @return An <CODE>Enumeration</CODE> of <CODE>String</CODE> objects, each <CODE>String</CODE>
+   * @return An <code>Enumeration</code> of <code>String</code> objects, each <code>String</code>
-   *         containing the name of a request parameter, or an empty <CODE>Enumeration</CODE> if the
+   *         containing the name of a request parameter, or an empty <code>Enumeration</code> if the
    *         request has no parameters.
    */
   public Enumeration getParameterNames();
 
   /**
-   * Returns an array of <CODE>String</CODE> objects containing all of the values the given request
+   * Returns an array of {@link java.lang.String String} objects containing all of the values the given request
-   * parameter has, or <CODE>null</CODE> if the parameter does not exist.<P>
+   * parameter has, or <code>null</code> if the parameter does not exist.<p>
    * If the parameter has a single value, the array has a length of 1.
    *
-   * @param name A <CODE>String</CODE> containing the name of the parameter whose value is requested.
+   * @param name A <code>String</code> containing the name of the parameter whose value is requested.
-   * @return An array of <CODE>String</CODE> objects containing the parameter's values.
+   * @return An array of <code>String</code> objects containing the parameter's values.
    * @see #getParameter(java.lang.String)
    */
   public String[] getParameterValues(String name);
 
   /**
-   * Returns <CODE>true</CODE> if the specified parameter is a file parameter, <CODE>false</CODE> if
+   * Returns <code>true</code> if the specified parameter is a file parameter, <code>false</code> if
-   * not.  If the parameter does not exist, the return value is <CODE>false</CODE>.
+   * not.  If the parameter does not exist, the return value is <code>false</code>.
    *
-   * @param name A <CODE>String</CODE> containing the name of the parameter to test.
+   * @param name A {@link java.lang.String String} containing the name of the parameter to test.
    * @return See above.
    */
   public boolean isFileParam(String name);
 
   /**
    * Returns the MIME type of the specified parameter.  If the type cannot be determined, the return
-   * value is <CODE>null</CODE>.<P>
+   * value is <code>null</code>.<p>
    * N.B.: For non-file parameters, or all parameters to a request that is not a file upload, the MIME
    * type is &quot;text/plain&quot;.
    *
-   * @param name A <CODE>String</CODE> containing the name of the parameter to test.
+   * @param name A {@link java.lang.String String} containing the name of the parameter to test.
    * @return See above.
    */
   public String getParameterType(String name);
 
   /**
    * Returns the size in bytes of the specified parameter.  If the size cannot be determined, the return
-   * value is -1.<P>
+   * value is -1.<p>
    * N.B.: For non-file parameters, or all parameters to a request that is not a file upload, the size
    * is the number of bytes occupied by the parameter, expressed in UTF-8 encoding.
    *
-   * @param name A <CODE>String</CODE> containing the name of the parameter to test.
+   * @param name A {@link java.lang.String String} containing the name of the parameter to test.
    * @return See above.
    */
   public int getParameterSize(String name);
 
   /**
-   * Returns an <CODE>InputStream</CODE> reading from the data of the named file parameter.  If the
+   * Returns an {@link java.io.InputStream InputStream} reading from the data of the named file parameter.  If the
-   * named parameter does not exist or is not a file parameter, returns <CODE>null;
+   * named parameter does not exist or is not a file parameter, returns <code>null;
    *
-   * @param name A <CODE>String</CODE> containing the name of the parameter whose value is requested.
+   * @param name A {@link java.lang.String String} containing the name of the parameter whose value is requested.
    * @return See above.
    * @exception com.silverwrist.util.ServletMultipartException If there is a problem retrieving
    *            the parameter data stream.
@@ -233,20 +236,20 @@ public interface RequestInput extends ServiceProvider
   public InputStream getParameterDataStream(String name) throws ServletMultipartException;
 
   /**
-   * Returns <CODE>true</CODE> if the parameter set reflects the clicking of an image button with a
+   * Returns <code>true</code> if the parameter set reflects the clicking of an image button with a
-   * specified name, <CODE>false</CODE> if not.
+   * specified name, <code>false</code> if not.
    *
-   * @param name A <CODE>String</CODE> containing the name of the image button to test.
+   * @param name A {@link java.lang.String String} containing the name of the image button to test.
    * @return See above.
    */
   public boolean isImageButtonClicked(String name);
 
   /**
-   * Returns the application-level attribute with the given name, or <CODE>null</CODE> if there is no
+   * Returns the application-level attribute with the given name, or <code>null</code> if there is no
    * attribute by that name.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the attribute.
+   * @param name A {@link java.lang.String String} specifying the name of the attribute.
-   * @return An <CODE>Object</CODE> containing the value of the attribute, or <CODE>null</CODE> if no
+   * @return An {@link java.lang.Object Object} containing the value of the attribute, or <code>null</code> if no
    *         attribute exists matching the given name.
    */
   public Object getAppAttribute(String name);
@@ -254,18 +257,18 @@ public interface RequestInput extends ServiceProvider
   /**
    * Sets the application-level attribute with the given name.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the attribute.
+   * @param name A {@link java.lang.String String} specifying the name of the attribute.
-   * @param o The object to be bound as the value of that attribute, or <CODE>null</CODE> if the binding
+   * @param o The object to be bound as the value of that attribute, or <code>null</code> if the binding
    *          is to be removed.
    */
   public void setAppAttribute(String name, Object o);
 
   /**
-   * Returns the session-level attribute with the given name, or <CODE>null</CODE> if there is no
+   * Returns the session-level attribute with the given name, or <code>null</code> if there is no
    * attribute by that name.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the attribute.
+   * @param name A {@link java.lang.String String} specifying the name of the attribute.
-   * @return An <CODE>Object</CODE> containing the value of the attribute, or <CODE>null</CODE> if no
+   * @return An {@link java.lang.Object Object} containing the value of the attribute, or <code>null</code> if no
    *         attribute exists matching the given name.
    */
   public Object getSessionAttribute(String name);
@@ -273,18 +276,18 @@ public interface RequestInput extends ServiceProvider
   /**
    * Sets the session-level attribute with the given name.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the attribute.
+   * @param name A {@link java.lang.String String} specifying the name of the attribute.
-   * @param o The object to be bound as the value of that attribute, or <CODE>null</CODE> if the binding
+   * @param o The object to be bound as the value of that attribute, or <code>null</code> if the binding
    *          is to be removed.
    */
   public void setSessionAttribute(String name, Object o);
 
   /**
-   * Returns the request-level attribute with the given name, or <CODE>null</CODE> if there is no
+   * Returns the request-level attribute with the given name, or <code>null</code> if there is no
    * attribute by that name.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the attribute.
+   * @param name A {@link java.lang.String String} specifying the name of the attribute.
-   * @return An <CODE>Object</CODE> containing the value of the attribute, or <CODE>null</CODE> if no
+   * @return An {@link java.lang.Object Object} containing the value of the attribute, or <code>null</code> if no
    *         attribute exists matching the given name.
    */
   public Object getRequestAttribute(String name);
@@ -292,8 +295,8 @@ public interface RequestInput extends ServiceProvider
   /**
    * Sets the request-level attribute with the given name.
    *
-   * @param name A <CODE>String</CODE> specifying the name of the attribute.
+   * @param name A {@link java.lang.String String} specifying the name of the attribute.
-   * @param o The object to be bound as the value of that attribute, or <CODE>null</CODE> if the binding
+   * @param o The object to be bound as the value of that attribute, or <code>null</code> if the binding
    *          is to be removed.
    */
   public void setRequestAttribute(String name, Object o);
@@ -329,8 +332,8 @@ public interface RequestInput extends ServiceProvider
   public void setLocation(String str);
 
   /**
-   * Returns <CODE>true</CODE> if the &quot;Log In&quot; link is to be displayed on the outer frame,
+   * Returns <code>true</code> if the &quot;Log In&quot; link is to be displayed on the outer frame,
-   * <CODE>false</CODE> if not.
+   * <code>false</code> if not.
    *
    * @return See above.
    */
@@ -339,8 +342,8 @@ public interface RequestInput extends ServiceProvider
   /**
    * Sets whether or not the &quot;Log In&quot; link is to be displayed on the outer frame.
    *
-   * @param val <CODE>true</CODE> to display the &quot;Log In&quot; link on the outer frame,
+   * @param val <code>true</code> to display the &quot;Log In&quot; link on the outer frame,
-   *            <CODE>false</CODE> to omit it.
+   *            <code>false</code> to omit it.
    */
   public void setDisplayLogin(boolean val);
 

src/com/silverwrist/venice/ui/conf/PostShortcutServlet.java

@@ -9,15 +9,15 @@
  * 
  * The Original Code is the Venice Web Communities System.
  * 
- * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@ricochet.com>,
  * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
- * Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * Copyright (C) 2001-2004 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
  * 
  * Contributor(s): 
  */
 package com.silverwrist.venice.ui.conf;
 
-import org.apache.log4j.*;
+import org.apache.log4j.Logger;
 import com.silverwrist.venice.core.*;
 import com.silverwrist.venice.db.PostLinkDecoder;
 import com.silverwrist.venice.except.*;
@@ -32,7 +32,7 @@ public class PostShortcutServlet extends BaseServlet implements LinkTypes
    *--------------------------------------------------------------------------------
    */
 
-  private static Category logger = Category.getInstance(PostShortcutServlet.class);
+  private static Logger logger = Logger.getLogger(PostShortcutServlet.class);
 
   /*--------------------------------------------------------------------------------
    * Internal operations

src/com/silverwrist/venice/ui/conf/TrackbackServlet.java

@@ -0,0 +1,188 @@
+/*
+ * The contents of this file are subject to the Mozilla Public License Version 1.1
+ * (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.mozilla.org/MPL/>.
+ * 
+ * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT
+ * WARRANTY OF ANY KIND, either express or implied. See the License for the specific
+ * language governing rights and limitations under the License.
+ * 
+ * The Original Code is the Venice Web Communities System.
+ * 
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@ricochet.com>,
+ * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
+ * Copyright (C) 2004 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * 
+ * Contributor(s): 
+ */
+package com.silverwrist.venice.ui.conf;
+
+import org.apache.log4j.Logger;
+import com.silverwrist.venice.core.*;
+import com.silverwrist.venice.db.PostLinkDecoder;
+import com.silverwrist.venice.except.*;
+import com.silverwrist.venice.ui.*;
+import com.silverwrist.venice.ui.helpers.*;
+import com.silverwrist.venice.ui.servlet.BaseServlet;
+
+public class TrackbackServlet extends BaseServlet
+{
+  /*--------------------------------------------------------------------------------
+   * Static data members
+   *--------------------------------------------------------------------------------
+   */
+
+  private static Logger logger = Logger.getLogger(TrackbackServlet.class);
+
+  private static final int INVALID = 0;
+  private static final int COMMUNITY = 1;
+  private static final int CONFERENCE = 2;
+  private static final int TOPIC = 3;
+  private static final int POST = 4;
+  private static final int POST_RANGE = 5;
+  private static final int POST_OE_RANGE = 6;
+
+  /*--------------------------------------------------------------------------------
+   * Internal operations
+   *--------------------------------------------------------------------------------
+   */
+
+  private static final int classifyPostLink(RequestInput req, PostLinkDecoder pld)
+  {
+    String s = pld.getCommunity();
+    if (s==null)
+      return INVALID;  // we must have the community or we're not valid
+    CommunityContext comm = null;
+    try
+    { // get the community context we're looking for
+      comm = req.getUser().getCommunityContext(s);
+      req.setRequestAttribute("current.community",comm);
+
+    } // end try
+    catch (DataException e)
+    { // can't find the community - we're screwed
+      logger.error("unable to decode community \"" + s + "\"",e);
+      return INVALID;
+
+    } // end catch
+
+    s = pld.getConference();
+    if (s==null)
+      return COMMUNITY;  // community link only
+
+    ConferenceContext conf = null;
+    try
+    { // get the conference context
+      conf = comm.getConferenceContext(s);
+      req.setRequestAttribute("current.conference",comm);
+
+    } // end try
+    catch (DataException e)
+    { // can't find the conference - we're screwed
+      logger.error("unable to decode conference \"" + s + "\"",e);
+      return INVALID;
+
+    } // end catch
+    catch (AccessError ae)
+    { // we can't get to the conference...
+      logger.error("AccessError getting conference \"" + s + "\"",ae);
+      return INVALID;
+
+    } // end catch
+
+    short tn = pld.getTopic();
+    if (tn==-1)
+      return CONFERENCE;  // only a conference locator
+
+    TopicContext topic = null;
+    try
+    { // get the resulting topic number
+      topic = conf.getTopic(tn);
+      req.setRequestAttribute("current.topic",comm);
+
+    } // end try
+    catch (DataException e)
+    { // we can't find the topic - we're screwed
+      logger.error("unable to decode topic \"" + tn + "\"",e);
+      return INVALID;
+
+    } // end catch
+    catch (AccessError ae)
+    { // we can't get to the topic...
+      logger.error("AccessError getting topic \"" + tn + "\"",ae);
+      return INVALID;
+
+    } // end catch
+
+    int fp = pld.getFirstPost();
+    if (fp==-1)
+      return TOPIC;  // just referencing the topic
+    int lp = pld.getLastPost();
+    if (fp==lp)
+      return POST;  // single post
+    if (lp==-1)
+      return POST_OE_RANGE;  // open-ended range of posts
+    return POST_RANGE;  // normal range of posts
+
+  } // end classifyPostLink
+
+  /*--------------------------------------------------------------------------------
+   * Implementations from class BaseServlet
+   *--------------------------------------------------------------------------------
+   */
+
+  public Object process(RequestInput req)
+  {
+    String raw_link = req.getPathInfo().substring(1);
+    PostLinkDecoder decoder;
+
+    if (logger.isDebugEnabled())
+      logger.debug("decoding post link: " + raw_link);
+
+    try
+    { // attempt to decode the path link information
+      decoder = new PostLinkDecoder(raw_link);
+
+    } // end try
+    catch (ValidationException e)
+    { // the post link decoder failed
+      logger.error("Post link decode failed!",e);
+      return new HTTPError(400,"Invalid post link \"" + raw_link + "\": " + e.getMessage());
+
+    } // end catch
+
+    // classify the post link and decode as much of it as we can
+    int what = classifyPostLink(req,decoder);
+    if (what==INVALID)
+      return new HTTPError(400,"Invalid post link \"" + raw_link + "\"");
+      
+    // at this point, trackback may only be applied to single posts, not ranges or anything higher
+    if (what!=POST)
+      return new HTTPError(400,"Trackback only applies to single posts");
+
+    TopicMessageContext msg = null;
+    try
+    { // get the message involved
+      TopicContext topic = (TopicContext)(req.getRequestAttribute("current.topic"));
+      msg = topic.getMessage(decoder.getFirstPost());
+
+    } // end try
+    catch (DataException e)
+    { // the post was not found
+      return new HTTPError(404,"Post not found: \"" + raw_link + "\"");
+
+    } // end catch
+    catch (AccessError e)
+    { // could not access the post
+      return new HTTPError(403,"Post not accessible: \"" + raw_link + "\"");
+
+    } // end catch
+
+    // TODO: POST = add trackback
+    // GET = get list of trackbacks, may be with either ?__mode=rss (default) or ?__mode=view
+
+    return null;
+
+  } // end process
+
+} // end class TrackbackServlet

src/com/silverwrist/venice/ui/helpers/HTTPError.java

@@ -9,9 +9,9 @@
  * 
  * The Original Code is the Venice Web Communities System.
  * 
- * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@ricochet.com>,
  * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
- * Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * Copyright (C) 2001-2004 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
  * 
  * Contributor(s): 
  */
@@ -29,7 +29,7 @@ public class HTTPError extends ThrowableContent implements ContentExecute
    *--------------------------------------------------------------------------------
    */
 
-  private int code;
+  private final int code;
 
   /*--------------------------------------------------------------------------------
    * Constructors