Changeset 24753 for main/trunk/greenstone3

Timestamp:

2011-10-13T12:05:21+13:00 (13 years ago)

Author:

sjm84

Message:

Some modifications to LibraryServlet to allow CGI formatted POST requests to go through the doGet method, also some initial code for handling file uploads

Location:

main/trunk/greenstone3

Files:

• src/java/org/greenstone/gsdl3/LibraryServlet.java (modified) (26 diffs)
• web/WEB-INF/lib/commons-fileupload-1.2.2.jar (added)

main/trunk/greenstone3/src/java/org/greenstone/gsdl3/LibraryServlet.java

@@ -5 +5 @@
 import org.greenstone.gsdl3.util.*;
 import org.greenstone.gsdl3.action.PageAction; // used to get the default action
+import org.greenstone.util.GlobalProperties;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
@@ -15 +16 @@
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.io.File;
 import java.lang.reflect.Type;
@@ -26 +29 @@
 
 // Apache Commons
+import org.apache.commons.fileupload.FileItem;
+import org.apache.commons.fileupload.disk.DiskFileItemFactory;
+import org.apache.commons.fileupload.servlet.ServletFileUpload;
 import org.apache.commons.lang3.*;
 
-/** a servlet to serve the greenstone library - we are using servlets instead
-* of cgi
-* the init method is called only once - the first time the servlet classes
-* are loaded. Each time a request comes in to the servlet, the session()
-* method is called in a new thread (calls doGet/doPut etc)
-* takes the a=p&p=home type args and builds a simple request to send to
-* its receptionist, which returns a result in html, cos output=html
-* is set in the request
-* 
-* 18/Jul/07 xiao
-* modify to make the cached parameters collection-specific.
-* Most of the work is done in doGet(), except adding an inner class UserSessionCache.
-* 
-* @see Receptionist
-*/
-public class LibraryServlet extends HttpServlet {
+/**
+ * a servlet to serve the greenstone library - we are using servlets instead of
+ * cgi the init method is called only once - the first time the servlet classes
+ * are loaded. Each time a request comes in to the servlet, the session() method
+ * is called in a new thread (calls doGet/doPut etc) takes the a=p&p=home type
+ * args and builds a simple request to send to its receptionist, which returns a
+ * result in html, cos output=html is set in the request
+ * 
+ * 18/Jul/07 xiao modify to make the cached parameters collection-specific. Most
+ * of the work is done in doGet(), except adding an inner class
+ * UserSessionCache.
+ * 
+ * @see Receptionist
+ */
+public class LibraryServlet extends HttpServlet
+{
 
     /** the receptionist to send messages to */
-    protected Receptionist recept=null;
-
-    /** the default language - is specified by setting a servlet param,
-* otherwise DEFAULT_LANG is used*/
-    protected String default_lang= null;
+    protected Receptionist recept = null;
+
+    /**
+     * the default language - is specified by setting a servlet param, otherwise
+     * DEFAULT_LANG is used
+     */
+    protected String default_lang = null;
 
     /** Whether or not client-side XSLT support should be exposed */
     protected boolean supports_client_xslt = false;
 
-    /** The default default - used if a default lang is not specified
-* in the servlet params */
+    /**
+     * The default default - used if a default lang is not specified in the
+     * servlet params
+     */
     protected final String DEFAULT_LANG = "en";
 
     /** container Document to create XML Nodes */
-    protected Document doc=null;
+    protected Document doc = null;
 
     /** a converter class to parse XML and create Docs */
-    protected XMLConverter converter=null;
-
-    /** the cgi stuff - the Receptionist can add new args to this
-*
-* its used by the servlet to determine what args to save */
+    protected XMLConverter converter = null;
+
+    /**
+     * the cgi stuff - the Receptionist can add new args to this
+     * 
+     * its used by the servlet to determine what args to save
+     */
     protected GSParams params = null;
 
-    /** user id - new one per session. This doesn't work if session state is saved between restarts - this requires this value to be saved too. */
+    /**
+     * user id - new one per session. This doesn't work if session state is
+     * saved between restarts - this requires this value to be saved too.
+     */
     protected int next_user_id = 0;
 
-    /** a hash that contains all the active session IDs mapped to the cached items
-*  It is updated whenever the whole site or a particular collection is reconfigured
-*  using the command a=s&sa=c or a=s&sa=c&c=xxx
-*  It is in the form: sid -> (UserSessionCache object)
-*/
+    /**
+     * a hash that contains all the active session IDs mapped to the cached
+     * items It is updated whenever the whole site or a particular collection is
+     * reconfigured using the command a=s&sa=c or a=s&sa=c&c=xxx It is in the
+     * form: sid -> (UserSessionCache object)
+     */
     protected Hashtable session_ids_table = new Hashtable();
 
-    /** the maximum interval that the cached info remains in session_ids_table (in seconds) 
-*  This is set in web.xml
-*/
+    /**
+     * the maximum interval that the cached info remains in session_ids_table
+     * (in seconds) This is set in web.xml
+     */
     protected int session_expiration = 1800;
 
     static Logger logger = Logger.getLogger(org.greenstone.gsdl3.LibraryServlet.class.getName());
 
-    /** initialise the servlet
-*/
-    public void init(ServletConfig config) throws ServletException {
+    /** initialise the servlet */
+    public void init(ServletConfig config) throws ServletException
+    {
         // always call super.init;
         super.init(config);
         // disable preferences - does this work anyway??
         //System.setProperty("java.util.prefs.PreferencesFactory", "org.greenstone.gsdl3.util.DisabledPreferencesFactory");
-        
+
         String library_name = config.getInitParameter(GSConstants.LIBRARY_NAME);
         String gsdl3_home = config.getInitParameter(GSConstants.GSDL3_HOME);
         String interface_name = config.getInitParameter(GSConstants.INTERFACE_NAME);
-        
-        String allowXslt = (String)config.getInitParameter(GSConstants.ALLOW_CLIENT_SIDE_XSLT);
+
+        String allowXslt = (String) config.getInitParameter(GSConstants.ALLOW_CLIENT_SIDE_XSLT);
         supports_client_xslt = allowXslt != null && allowXslt.equals("true");
-        
+
         this.default_lang = config.getInitParameter(GSConstants.DEFAULT_LANG);
         String sess_expire = config.getInitParameter(GSXML.SESSION_EXPIRATION);
-        
-        if (sess_expire != null && !sess_expire.equals("")) {
+
+        if (sess_expire != null && !sess_expire.equals(""))
+        {
             this.session_expiration = Integer.parseInt(sess_expire);
         }
-        
-        if (library_name == null || interface_name ==null) {
+
+        if (library_name == null || interface_name == null)
+        {
             // must have this
             System.err.println("initialisation parameters not all set!");
@@ -115 +134 @@
             System.exit(1);
         }
-        
+
         String site_name = config.getInitParameter(GSConstants.SITE_NAME);
         String remote_site_name = null;
         String remote_site_type = null;
         String remote_site_address = null;
-        
-        if (site_name == null) {
+
+        if (site_name == null)
+        {
             // no site, try for communicator
             remote_site_name = config.getInitParameter("remote_site_name");
             remote_site_type = config.getInitParameter("remote_site_type");
             remote_site_address = config.getInitParameter("remote_site_address");
-            if (remote_site_name == null || remote_site_type == null || remote_site_address == null) {
+            if (remote_site_name == null || remote_site_type == null || remote_site_address == null)
+            {
                 System.err.println("initialisation paramters not all set!");
                 System.err.println("if site_name is not set, then you must have remote_site_name, remote_site_type and remote_site_address set");
@@ -132 +153 @@
             }
         }
-        
-        if (this.default_lang == null) {
+
+        if (this.default_lang == null)
+        {
             // choose english
             this.default_lang = DEFAULT_LANG;
         }
-        
+
         HashMap config_params = new HashMap();
-        
+
         config_params.put(GSConstants.LIBRARY_NAME, library_name);
-        config_params.put(GSConstants.INTERFACE_NAME, interface_name);  
+        config_params.put(GSConstants.INTERFACE_NAME, interface_name);
         config_params.put(GSConstants.ALLOW_CLIENT_SIDE_XSLT, supports_client_xslt);
-        
-        if (site_name != null) {
+
+        if (site_name != null)
+        {
             config_params.put(GSConstants.SITE_NAME, site_name);
         }
         this.converter = new XMLConverter();
         this.doc = this.converter.newDOM();
-        
+
         // the receptionist -the servlet will talk to this
-        String recept_name = (String)config.getInitParameter("receptionist_class");
-        if (recept_name == null) {
+        String recept_name = (String) config.getInitParameter("receptionist_class");
+        if (recept_name == null)
+        {
             this.recept = new DefaultReceptionist();
-        } else {
-            try {
-                this.recept = (Receptionist)Class.forName("org.greenstone.gsdl3.core."+recept_name).newInstance();
-            } catch (Exception e) { // cant use this new one, so use normal one
-                System.err.println("LibraryServlet configure exception when trying to use a new Receptionist "+recept_name+": "+e.getMessage());
+        }
+        else
+        {
+            try
+            {
+                this.recept = (Receptionist) Class.forName("org.greenstone.gsdl3.core." + recept_name).newInstance();
+            }
+            catch (Exception e)
+            { // cant use this new one, so use normal one
+                System.err.println("LibraryServlet configure exception when trying to use a new Receptionist " + recept_name + ": " + e.getMessage());
                 e.printStackTrace();
                 this.recept = new DefaultReceptionist();
@@ -164 +193 @@
         }
         this.recept.setConfigParams(config_params);
-        
+
         // the receptionist uses a MessageRouter or Communicator to send its requests to. We either create a MessageRouter here for the designated site (if site_name set), or we create a Communicator for a remote site. The is given to teh Receptionist, and the servlet never talks to it again.directly.
-        if (site_name != null) {
-            String mr_name = (String)config.getInitParameter("messagerouter_class");
+        if (site_name != null)
+        {
+            String mr_name = (String) config.getInitParameter("messagerouter_class");
             MessageRouter message_router = null;
-            if (mr_name == null) { // just use the normal MR
+            if (mr_name == null)
+            { // just use the normal MR
                 message_router = new MessageRouter();
-            } else { // try the specified one
-                try {
-                    message_router = (MessageRouter)Class.forName("org.greenstone.gsdl3.core."+mr_name).newInstance();
-                } catch (Exception e) { // cant use this new one, so use normal one
-                    System.err.println("LibraryServlet configure exception when trying to use a new MessageRouter "+mr_name+": "+e.getMessage());
+            }
+            else
+            { // try the specified one
+                try
+                {
+                    message_router = (MessageRouter) Class.forName("org.greenstone.gsdl3.core." + mr_name).newInstance();
+                }
+                catch (Exception e)
+                { // cant use this new one, so use normal one
+                    System.err.println("LibraryServlet configure exception when trying to use a new MessageRouter " + mr_name + ": " + e.getMessage());
                     e.printStackTrace();
                     message_router = new MessageRouter();
                 }
             }
-            
+
             message_router.setSiteName(site_name);
             message_router.setLibraryName(library_name);
             message_router.configure();
             this.recept.setMessageRouter(message_router);
-        } else {
+        }
+        else
+        {
             // talking to a remote site, create a communicator
             Communicator communicator = null;
@@ -193 +231 @@
             site_elem.setAttribute(GSXML.NAME_ATT, remote_site_name);
             site_elem.setAttribute(GSXML.ADDRESS_ATT, remote_site_address);
-            
-            if (remote_site_type.equals(GSXML.COMM_TYPE_SOAP_JAVA)) {
+
+            if (remote_site_type.equals(GSXML.COMM_TYPE_SOAP_JAVA))
+            {
                 communicator = new SOAPCommunicator();
-            } else {
-                System.err.println("LibraryServlet.init Error: invalid Communicator type: "+remote_site_type);
+            }
+            else
+            {
+                System.err.println("LibraryServlet.init Error: invalid Communicator type: " + remote_site_type);
                 System.exit(1);
             }
-            
-            if (!communicator.configure(site_elem)) {
+
+            if (!communicator.configure(site_elem))
+            {
                 System.err.println("LibraryServlet.init Error: Couldn't configure communicator");
                 System.exit(1);
@@ -207 +249 @@
             this.recept.setMessageRouter(communicator);
         }
-        
+
         // the params arg thingy
-        
-        String params_name = (String)config.getInitParameter("params_class");
-        if (params_name == null) {
+
+        String params_name = (String) config.getInitParameter("params_class");
+        if (params_name == null)
+        {
             this.params = new GSParams();
-        } else {
-            try {
-                this.params = (GSParams)Class.forName("org.greenstone.gsdl3.util."+params_name).newInstance();
-            } catch (Exception e) {
-                System.err.println("LibraryServlet configure exception when trying to use a new params thing "+params_name+": "+e.getMessage());
+        }
+        else
+        {
+            try
+            {
+                this.params = (GSParams) Class.forName("org.greenstone.gsdl3.util." + params_name).newInstance();
+            }
+            catch (Exception e)
+            {
+                System.err.println("LibraryServlet configure exception when trying to use a new params thing " + params_name + ": " + e.getMessage());
                 e.printStackTrace();
                 this.params = new GSParams();
@@ -225 +273 @@
         this.recept.setParams(this.params);
         this.recept.configure();
-        
+
     }
 
-
-    private void logUsageInfo(HttpServletRequest request){
+    private void logUsageInfo(HttpServletRequest request)
+    {
         String usageInfo = "";
-        
+
         //session-info: get params stored in the session
         HttpSession session = request.getSession(true);
         Enumeration attributeNames = session.getAttributeNames();
-        while(attributeNames.hasMoreElements()) {
-            String name = (String)attributeNames.nextElement();
-            usageInfo +=name+"="+session.getAttribute(name)+" ";
+        while (attributeNames.hasMoreElements())
+        {
+            String name = (String) attributeNames.nextElement();
+            usageInfo += name + "=" + session.getAttribute(name) + " ";
+        }
+
+        //logged info = general-info + session-info
+        usageInfo = request.getServletPath() + " " + //serlvet
+        "[" + request.getQueryString() + "]" + " " + //the query string
+        "[" + usageInfo.trim() + "]" + " " + // params stored in a session
+        request.getRemoteAddr() + " " + //remote address
+        request.getRequestedSessionId() + " " + //session id
+        request.getHeader("user-agent") + " "; //the remote brower info
+
+        logger.info(usageInfo);
+
+    }
+
+    public class UserSessionCache implements HttpSessionBindingListener
+    {
+
+        String session_id = "";
+
+        /**
+         * a hash that maps the session ID to a hashtable that maps the
+         * coll_name to its parameters coll_name -> Hashtable (param_name ->
+         * param_value)
+         */
+        protected Hashtable coll_name_params_table = null;
+
+        public UserSessionCache(String id, Hashtable table)
+        {
+            session_id = id;
+            coll_name_params_table = (table == null) ? new Hashtable() : table;
+        }
+
+        protected void cleanupCache(String coll_name)
+        {
+            if (coll_name_params_table.containsKey(coll_name))
+            {
+                coll_name_params_table.remove(coll_name);
+            }
+        }
+
+        protected Hashtable getParamsTable()
+        {
+            return coll_name_params_table;
+        }
+
+        public void valueBound(HttpSessionBindingEvent event)
+        {
+            // Do nothing
+        }
+
+        public void valueUnbound(HttpSessionBindingEvent event)
+        {
+            if (session_ids_table.containsKey(session_id))
+            {
+                session_ids_table.remove(session_id);
+            }
+        }
+
+        public int tableSize()
+        {
+            return (coll_name_params_table == null) ? 0 : coll_name_params_table.size();
+        }
+
+    }
+
+    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
+    {
+        logUsageInfo(request);
+
+        String query_string;
+        if(request.getMethod().equals("GET"))
+        {
+            query_string = request.getQueryString();    
+        }
+        else if(request.getMethod().equals("POST"))
+        {
+            query_string = "";
+            Map paramMap = request.getParameterMap();
+            Iterator keyIter = paramMap.keySet().iterator();
+            
+            while(keyIter.hasNext())
+            {
+                String current = (String)keyIter.next();
+                query_string += current + "=" + ((String[])paramMap.get(current))[0];
+                if(keyIter.hasNext())
+                {
+                    query_string += "&";
+                }
+            }
+            
+            DiskFileItemFactory fileItemFactory = new DiskFileItemFactory();
+
+            int sizeLimit = System.getProperties().containsKey("servlet.upload.filesize.limit") ? Integer.parseInt(System.getProperty("servlet.upload.filesize.limit")) : 20 * 1024 * 1024;
+
+            fileItemFactory.setSizeThreshold(sizeLimit);
+            fileItemFactory.setRepository(new File(GlobalProperties.getGSDL3Home() + File.separator + "tmp"));
+
+            ServletFileUpload uploadHandler = new ServletFileUpload(fileItemFactory);
+
+            try
+            {
+                List items = uploadHandler.parseRequest(request);
+                Iterator iter = items.iterator();
+                while(iter.hasNext())
+                {
+                    FileItem current = (FileItem) iter.next();
+                    if(current.isFormField())
+                    {
+                        query_string += current.getFieldName() + "=" + current.getString();
+                        if(iter.hasNext())
+                        {
+                            query_string += "&";
+                        }
+                    }
+                    else
+                    {
+                        File file = new File(GlobalProperties.getGSDL3Home() + File.separator + "tmp" + File.separator + current.getName());
+                        current.write(file);
+                    }
+                }
+            }
+            catch (Exception e) 
+            {
+                logger.error("Exception in LibraryServlet -> " + e.getMessage());
+            }
+            
+            if(query_string.equals(""))
+            {
+                query_string = null;
+            }
+        }
+        else
+        {
+            query_string = null;
         }
         
-        //logged info = general-info + session-info
-        usageInfo =
-        request.getServletPath()+" "+ //serlvet
-        "["+request.getQueryString()+"]" +" "+ //the query string
-        "["+usageInfo.trim()+"]" +" "+ // params stored in a session
-        request.getRemoteAddr()+" "+   //remote address
-        request.getRequestedSessionId()+" "+ //session id
-        request.getHeader("user-agent")+" "; //the remote brower info
-        
-        logger.info(usageInfo);
-        
-    }
-
-    public class UserSessionCache implements HttpSessionBindingListener {
-
-        String session_id = "";
-        
-        /** a hash that maps the session ID to a hashtable that maps the coll_name to its parameters 
-    *  coll_name -> Hashtable (param_name -> param_value)
-    */
-        protected Hashtable coll_name_params_table = null;
-        
-        public UserSessionCache(String id, Hashtable table) {
-            session_id = id;      
-            coll_name_params_table = (table == null)? new Hashtable() : table;      
-        }
-
-        protected void cleanupCache(String coll_name) {
-            if (coll_name_params_table.containsKey(coll_name)) {
-                coll_name_params_table.remove(coll_name);
-            }
-        }
-
-        protected Hashtable getParamsTable() {
-            return coll_name_params_table;
-        }
-
-        public void valueBound(HttpSessionBindingEvent event) {
-            // Do nothing
-        }
-
-        public void valueUnbound(HttpSessionBindingEvent event) {
-            if(session_ids_table.containsKey(session_id)) {
-                session_ids_table.remove(session_id);
-            }
-        }
-
-        public int tableSize() {
-            return (coll_name_params_table == null)? 0 : coll_name_params_table.size();
-        }
-
-    }
-
-    public void doGet (HttpServletRequest request, HttpServletResponse response)
-    throws ServletException, IOException {
-        logUsageInfo (request);
-
-        String query_string = request.getQueryString();
-        if (query_string!=null){
+        if (query_string != null)
+        {
             String[] query_arr = StringUtils.split(query_string, "&");
             boolean redirect = false;
@@ -305 +431 @@
             String[] nameval = new String[2]; // Reuse it for memory efficiency purposes    
 
-            for (int i=0;i<query_arr.length;i++){
-
-                if (query_arr[i].startsWith("el=")){
-                    if (query_arr[i].substring(query_arr[i].indexOf("=")+1,query_arr[i].length()).equals("direct")){
+            for (int i = 0; i < query_arr.length; i++)
+            {
+                if (query_arr[i].startsWith("el="))
+                {
+                    if (query_arr[i].substring(query_arr[i].indexOf("=") + 1, query_arr[i].length()).equals("direct"))
+                    {
                         redirect = true;
                     }
-                }else if(query_arr[i].startsWith("href=")){
-                    href = query_arr[i].substring(query_arr[i].indexOf("=")+1,query_arr[i].length());
+                }
+                else if (query_arr[i].startsWith("href="))
+                {
+                    href = query_arr[i].substring(query_arr[i].indexOf("=") + 1, query_arr[i].length());
                     href = StringUtils.replace(href, "%2f", "/");
                     href = StringUtils.replace(href, "%7e", "~");
                     href = StringUtils.replace(href, "%3f", "?");
                     href = StringUtils.replace(href, "%3A", "\\:");
-                }else if(query_arr[i].startsWith("rl=")){
-                    rl = query_arr[i].substring(query_arr[i].indexOf("=")+1,query_arr[i].length());
+                }
+                else if (query_arr[i].startsWith("rl="))
+                {
+                    rl = query_arr[i].substring(query_arr[i].indexOf("=") + 1, query_arr[i].length());
                 }
             }
@@ -325 +457 @@
             //"rl=0" this is an external link
             //"rl=1" this is an internal link
-            if ((redirect) && (href != null) && (rl.equals("0"))){// This is an external link, the web page is re-directed to the external URL (&el=&rl=0&href="http://...")
+            if ((redirect) && (href != null) && (rl.equals("0")))
+            {// This is an external link, the web page is re-directed to the external URL (&el=&rl=0&href="http://...")
                 response.setContentType("text/xml");
                 response.sendRedirect(href);
             }
         }
-        
+
         // Nested Diagnostic Configurator to identify the client for
-        HttpSession session = request.getSession (true);
+        HttpSession session = request.getSession(true);
         session.setMaxInactiveInterval(session_expiration);
-        String uid = (String)session.getAttribute (GSXML.USER_ID_ATT);
-        if (uid ==null) {
-            uid = ""+getNextUserId ();
-            session.setAttribute (GSXML.USER_ID_ATT, uid);
-        }
-        request.setCharacterEncoding ("UTF-8");
-        response.setContentType ("text/html;charset=UTF-8");
-        PrintWriter out = response.getWriter ();
-        
-        String lang = request.getParameter (GSParams.LANGUAGE);
-        if (lang==null || lang.equals ("")) {
+        String uid = (String) session.getAttribute(GSXML.USER_ID_ATT);
+        if (uid == null)
+        {
+            uid = "" + getNextUserId();
+            session.setAttribute(GSXML.USER_ID_ATT, uid);
+        }
+        request.setCharacterEncoding("UTF-8");
+        response.setContentType("text/html;charset=UTF-8");
+        PrintWriter out = response.getWriter();
+
+        String lang = request.getParameter(GSParams.LANGUAGE);
+        if (lang == null || lang.equals(""))
+        {
             // try the session cached lang
-            lang = (String)session.getAttribute (GSParams.LANGUAGE);
-            if (lang==null || lang.equals ("")) {
+            lang = (String) session.getAttribute(GSParams.LANGUAGE);
+            if (lang == null || lang.equals(""))
+            {
                 // still not set, use the default
                 lang = this.default_lang;
             }
         }
-        
+
         // set the lang in the session
-        session.setAttribute (GSParams.LANGUAGE, lang);
-        
-        String output = request.getParameter (GSParams.OUTPUT);
-        if (output==null || output.equals ("")) {
+        session.setAttribute(GSParams.LANGUAGE, lang);
+
+        String output = request.getParameter(GSParams.OUTPUT);
+        if (output == null || output.equals(""))
+        {
             output = "html"; // uses html by default
         }
-        
+
         // If server output, force a switch to traditional interface
         //output = (output.equals("server")) ? "html" : output;
-        
+
         // Force change the output mode if client-side XSLT is supported - server vs. client
         // BUT only if the library allows client-side transforms    
-        if(supports_client_xslt) {
+        if (supports_client_xslt)
+        {
             // MUST be done before the xml_message is built
             Cookie[] cookies = request.getCookies();
             Cookie xsltCookie = null;
-            
+
             // The client has cookies enabled and a value set - use it!
-            if(cookies != null) {
-                for(Cookie c : cookies) {
-                    if(c.getName().equals("supportsXSLT")) {
+            if (cookies != null)
+            {
+                for (Cookie c : cookies)
+                {
+                    if (c.getName().equals("supportsXSLT"))
+                    {
                         xsltCookie = c;
                         break;
@@ -382 +523 @@
             }
         }
-        
+
         // the request to the receptionist
-        Element xml_message = this.doc.createElement (GSXML.MESSAGE_ELEM);
-        Element xml_request = GSXML.createBasicRequest (this.doc, GSXML.REQUEST_TYPE_PAGE, "", lang, uid);
-        xml_request.setAttribute (GSXML.OUTPUT_ATT, output);
-        
-        xml_message.appendChild (xml_request);
-        
-        String action = request.getParameter (GSParams.ACTION);
-        String subaction = request.getParameter (GSParams.SUBACTION);
+        Element xml_message = this.doc.createElement(GSXML.MESSAGE_ELEM);
+        Element xml_request = GSXML.createBasicRequest(this.doc, GSXML.REQUEST_TYPE_PAGE, "", lang, uid);
+        xml_request.setAttribute(GSXML.OUTPUT_ATT, output);
+
+        xml_message.appendChild(xml_request);
+
+        String action = request.getParameter(GSParams.ACTION);
+        String subaction = request.getParameter(GSParams.SUBACTION);
         String collection = request.getParameter(GSParams.COLLECTION);
         String service = request.getParameter(GSParams.SERVICE);
@@ -398 +539 @@
         // commands are issued (and also don't need to do caching for this request)
         boolean should_cache = true;
-        if(action != null && action.equals(GSParams.SYSTEM)) {
+        if (action != null && action.equals(GSParams.SYSTEM))
+        {
             should_cache = false;
 
             // we may want to remove all collection cache info, or just a specific collection
-            boolean clean_all = true; 
+            boolean clean_all = true;
             String clean_collection = null;
             // system commands are to activate/deactivate stuff
@@ -408 +550 @@
             // don't like the fact that it is hard coded here
             String coll = request.getParameter(GSParams.SYSTEM_CLUSTER);
-            if (coll != null && !coll.equals("")) {
+            if (coll != null && !coll.equals(""))
+            {
                 clean_all = false;
                 clean_collection = coll;
-            } else {
+            }
+            else
+            {
                 // check other system types
-                if (subaction.equals("a") || subaction.equals("d")) {
+                if (subaction.equals("a") || subaction.equals("d"))
+                {
                     String module_name = request.getParameter("sn");
-                    if (module_name != null && !module_name.equals("")) {
+                    if (module_name != null && !module_name.equals(""))
+                    {
                         clean_all = false;
                         clean_collection = module_name;
@@ -421 +568 @@
                 }
             }
-            if (clean_all) {
-                session_ids_table = new Hashtable(); 
+            if (clean_all)
+            {
+                session_ids_table = new Hashtable();
                 session.removeAttribute(GSXML.USER_SESSION_CACHE_ATT);
-            } else {
+            }
+            else
+            {
                 // just clean up info for clean_collection
                 ArrayList cache_list = new ArrayList(session_ids_table.values());
-                for (int i=0; i<cache_list.size(); i++) {
-                    UserSessionCache cache = (UserSessionCache)cache_list.get(i);
+                for (int i = 0; i < cache_list.size(); i++)
+                {
+                    UserSessionCache cache = (UserSessionCache) cache_list.get(i);
                     cache.cleanupCache(clean_collection);
                 }
-                
-            }
-
-        }
-        
+
+            }
+
+        }
+
         // cache_key is the collection name, or service name
         String cache_key = collection;
-        if (cache_key == null || cache_key.equals("")) {
+        if (cache_key == null || cache_key.equals(""))
+        {
             cache_key = service;
         }
-        
+
         // logger.info("should_cache= " + should_cache);
 
@@ -447 +599 @@
         //about the same collection as the last session or not.
         Enumeration attributeNames = session.getAttributeNames();
-        while(attributeNames.hasMoreElements()) {
-            String name = (String)attributeNames.nextElement();
-            if (!name.equals (GSXML.USER_SESSION_CACHE_ATT)
-                    && !name.equals (GSParams.LANGUAGE) 
-                    && !name.equals (GSXML.USER_ID_ATT)) {
+        while (attributeNames.hasMoreElements())
+        {
+            String name = (String) attributeNames.nextElement();
+            if (!name.equals(GSXML.USER_SESSION_CACHE_ATT) && !name.equals(GSParams.LANGUAGE) && !name.equals(GSXML.USER_ID_ATT))
+            {
 
                 session.removeAttribute(name);
             }
         }
-        
+
         UserSessionCache session_cache = null;
-        Hashtable param_table = null;    
+        Hashtable param_table = null;
         Hashtable table = null;
         String sid = session.getId();
-        if (should_cache == true && cache_key != null && !cache_key.equals("")) {
-            if (session_ids_table.containsKey(sid)) {
-                session_cache = (UserSessionCache)session_ids_table.get(sid);
+        if (should_cache == true && cache_key != null && !cache_key.equals(""))
+        {
+            if (session_ids_table.containsKey(sid))
+            {
+                session_cache = (UserSessionCache) session_ids_table.get(sid);
                 param_table = session_cache.getParamsTable();
                 logger.info("collections in table: " + tableToString(param_table));
-                if (param_table.containsKey(cache_key)) {
+                if (param_table.containsKey(cache_key))
+                {
                     //logger.info("existing table: " + collection);
-                    table = (Hashtable)param_table.get(cache_key);
-                } else {
+                    table = (Hashtable) param_table.get(cache_key);
+                }
+                else
+                {
                     table = new Hashtable();
                     param_table.put(cache_key, table);
                     //logger.info("new table: " + collection);
                 }
-            } else {
+            }
+            else
+            {
                 param_table = new Hashtable();
                 table = new Hashtable();
@@ -485 +644 @@
         }
 
-        if (action==null || action.equals ("")) {
+        if (action == null || action.equals(""))
+        {
             // should we do all the following stuff if using default page?
             // display the home page  - the default page
-            xml_request.setAttribute (GSXML.ACTION_ATT, "p");
-            xml_request.setAttribute (GSXML.SUBACTION_ATT, PageAction.HOME_PAGE);
-        }
-        else {
-            xml_request.setAttribute (GSXML.ACTION_ATT, action);
-            if (subaction != null) {
-                xml_request.setAttribute (GSXML.SUBACTION_ATT, subaction);
-            }
-            
+            xml_request.setAttribute(GSXML.ACTION_ATT, "p");
+            xml_request.setAttribute(GSXML.SUBACTION_ATT, PageAction.HOME_PAGE);
+        }
+        else
+        {
+            xml_request.setAttribute(GSXML.ACTION_ATT, action);
+            if (subaction != null)
+            {
+                xml_request.setAttribute(GSXML.SUBACTION_ATT, subaction);
+            }
+
             //  create the param list for the greenstone request - includes
             // the params from the current request and any others from the saved session
-            Element xml_param_list = this.doc.createElement (GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER);
-            xml_request.appendChild (xml_param_list);
-            
-            Enumeration params = request.getParameterNames ();
-            while(params.hasMoreElements ()) {
-                String name = (String)params.nextElement ();
-                if (!name.equals (GSParams.ACTION) 
-                        && !name.equals (GSParams.SUBACTION) 
-                        && !name.equals (GSParams.LANGUAGE) 
-                        && !name.equals (GSParams.OUTPUT)) {// we have already dealt with these
-                    
-                    String value="";
-                    String [] values = request.getParameterValues (name);
+            Element xml_param_list = this.doc.createElement(GSXML.PARAM_ELEM + GSXML.LIST_MODIFIER);
+            xml_request.appendChild(xml_param_list);
+
+            Enumeration params = request.getParameterNames();
+            while (params.hasMoreElements())
+            {
+                String name = (String) params.nextElement();
+                if (!name.equals(GSParams.ACTION) && !name.equals(GSParams.SUBACTION) && !name.equals(GSParams.LANGUAGE) && !name.equals(GSParams.OUTPUT))
+                {// we have already dealt with these
+
+                    String value = "";
+                    String[] values = request.getParameterValues(name);
                     value = values[0];
-                    if (values.length > 1) {
-                        for (int i=1; i< values.length; i++) {
-                            value += ","+values[i];
+                    if (values.length > 1)
+                    {
+                        for (int i = 1; i < values.length; i++)
+                        {
+                            value += "," + values[i];
                         }
                     }
                     // either add it to the param list straight away, or save it to the session and add it later
-                    if (this.params.shouldSave (name) && table != null) {
+                    if (this.params.shouldSave(name) && table != null)
+                    {
                         table.put(name, value);
-                    } else {
-                        Element param = this.doc.createElement (GSXML.PARAM_ELEM);
-                        param.setAttribute (GSXML.NAME_ATT, name);
-                        param.setAttribute (GSXML.VALUE_ATT, GSXML.xmlSafe (value));
-                        xml_param_list.appendChild (param);
+                    }
+                    else
+                    {
+                        Element param = this.doc.createElement(GSXML.PARAM_ELEM);
+                        param.setAttribute(GSXML.NAME_ATT, name);
+                        param.setAttribute(GSXML.VALUE_ATT, GSXML.xmlSafe(value));
+                        xml_param_list.appendChild(param);
                     }
                 }
@@ -531 +697 @@
             //put everything in the table into the session
             // do we need to do this? why not just put from table into param list
-            if (table != null) {
-                Enumeration keys = table.keys ();
-                while(keys.hasMoreElements ()) {
-                    String name = (String)keys.nextElement();
-                    session.setAttribute(name, (String)table.get(name));
-                }
-            }
-            
+            if (table != null)
+            {
+                Enumeration keys = table.keys();
+                while (keys.hasMoreElements())
+                {
+                    String name = (String) keys.nextElement();
+                    session.setAttribute(name, (String) table.get(name));
+                }
+            }
+
             // put in all the params from the session cache
-            params = session.getAttributeNames ();
-            while(params.hasMoreElements ()) {
-                String name = (String)params.nextElement ();
-                
-                if ( !name.equals (GSXML.USER_SESSION_CACHE_ATT) 
-                        && !name.equals (GSParams.LANGUAGE) 
-                        && !name.equals (GSXML.USER_ID_ATT)) { 
+            params = session.getAttributeNames();
+            while (params.hasMoreElements())
+            {
+                String name = (String) params.nextElement();
+
+                if (!name.equals(GSXML.USER_SESSION_CACHE_ATT) && !name.equals(GSParams.LANGUAGE) && !name.equals(GSXML.USER_ID_ATT))
+                {
 
                     // lang and uid are stored but we dont want it in the param list cos its already in the request
-                    Element param = this.doc.createElement (GSXML.PARAM_ELEM);
-                    param.setAttribute (GSXML.NAME_ATT, name);
-                    String value =  GSXML.xmlSafe ((String)session.getAttribute (name));
+                    Element param = this.doc.createElement(GSXML.PARAM_ELEM);
+                    param.setAttribute(GSXML.NAME_ATT, name);
+                    String value = GSXML.xmlSafe((String) session.getAttribute(name));
 
                     // ugly hack to undo : escaping
                     value = StringUtils.replace(value, "%3A", "\\:");
-                    param.setAttribute (GSXML.VALUE_ATT,value);
-                    xml_param_list.appendChild (param);
-                }
-            }
-        }
-        
-        if (!output.equals("html") && !output.equals("server") && !output.equals("xsltclient")) {
-            response.setContentType ("text/xml"); // for now use text
-        }
-        
+                    param.setAttribute(GSXML.VALUE_ATT, value);
+                    xml_param_list.appendChild(param);
+                }
+            }
+        }
+
+        if (!output.equals("html") && !output.equals("server") && !output.equals("xsltclient"))
+        {
+            response.setContentType("text/xml"); // for now use text
+        }
+
         //Add custom HTTP headers if requested
         String httpHeadersParam = request.getParameter(GSParams.HTTPHEADERFIELDS);
@@ -570 +739 @@
         {
             Gson gson = new Gson();
-            Type type = new TypeToken<List<Map<String,String>>>() {}.getType();
-            List<Map<String,String>> httpHeaders = gson.fromJson(httpHeadersParam, type);
-            if (httpHeaders != null && httpHeaders.size() > 0) {
-                
-                for(int j = 0; j < httpHeaders.size(); j++)
-                {
-                    Map nameValueMap = (Map)httpHeaders.get(j);
-                    String name = (String)nameValueMap.get("name");
-                    String value = (String)nameValueMap.get("value");
-                    
-                    if(name != null && value != null)
+            Type type = new TypeToken<List<Map<String, String>>>()
+            {
+            }.getType();
+            List<Map<String, String>> httpHeaders = gson.fromJson(httpHeadersParam, type);
+            if (httpHeaders != null && httpHeaders.size() > 0)
+            {
+
+                for (int j = 0; j < httpHeaders.size(); j++)
+                {
+                    Map nameValueMap = (Map) httpHeaders.get(j);
+                    String name = (String) nameValueMap.get("name");
+                    String value = (String) nameValueMap.get("value");
+
+                    if (name != null && value != null)
                     {
                         response.setHeader(name, value);
@@ -587 +759 @@
             }
         }
-        
+
         Node xml_result = this.recept.process(xml_message);
-        encodeURLs (xml_result, response);
-        out.println (this.converter.getPrettyString (xml_result));
-        
+        encodeURLs(xml_result, response);
+        out.println(this.converter.getPrettyString(xml_result));
+
         displaySize(session_ids_table);
 
@@ -597 +769 @@
 
     //a debugging method
-    private void displaySize(Hashtable table) {
-        if(table == null) {
+    private void displaySize(Hashtable table)
+    {
+        if (table == null)
+        {
             logger.info("cached table is null");
             return;
         }
-        if (table.size() == 0) {
+        if (table.size() == 0)
+        {
             logger.info("cached table size is zero");
             return;
@@ -608 +783 @@
         int num_cached_coll = 0;
         ArrayList cache_list = new ArrayList(table.values());
-        for (int i=0; i<cache_list.size(); i++) {
-            num_cached_coll += ((UserSessionCache)cache_list.get(i)).tableSize();
+        for (int i = 0; i < cache_list.size(); i++)
+        {
+            num_cached_coll += ((UserSessionCache) cache_list.get(i)).tableSize();
         }
         logger.info("Number of sessions : total number of cached collection info = " + table.size() + " : " + num_cached_coll);
@@ -615 +791 @@
 
     /** merely a debugging method! */
-    private String tableToString(Hashtable table) {
+    private String tableToString(Hashtable table)
+    {
         String str = "";
-        Enumeration keys = table.keys ();
-        while(keys.hasMoreElements ()) {
-            String name = (String)keys.nextElement();
+        Enumeration keys = table.keys();
+        while (keys.hasMoreElements())
+        {
+            String name = (String) keys.nextElement();
             str += name + ", ";
         }
@@ -625 +803 @@
     }
 
-    /** this goes through each URL and adds in a session id if needed--
-* its needed if the browser doesn't accept cookies
-* also escapes things if needed
-*/
-    protected void encodeURLs(Node dataNode, HttpServletResponse response) {
-        
-        if (dataNode == null) {
+    /**
+     * this goes through each URL and adds in a session id if needed-- its
+     * needed if the browser doesn't accept cookies also escapes things if
+     * needed
+     */
+    protected void encodeURLs(Node dataNode, HttpServletResponse response)
+    {
+
+        if (dataNode == null)
+        {
             return;
         }
 
-        Element data =null;
+        Element data = null;
 
         short nodeType = dataNode.getNodeType();
-        if (nodeType == Node.DOCUMENT_NODE) {
-            Document docNode = (Document)dataNode;
-            data = docNode.getDocumentElement() ;
-        }
-        else {
-            data = (Element)dataNode;
-        }
-
-        if ( data != null ) {
+        if (nodeType == Node.DOCUMENT_NODE)
+        {
+            Document docNode = (Document) dataNode;
+            data = docNode.getDocumentElement();
+        }
+        else
+        {
+            data = (Element) dataNode;
+        }
+
+        if (data != null)
+        {
 
             // get all the <a> elements
@@ -653 +837 @@
             int hrefscount = hrefs.getLength();
 
-            for (int i=0; hrefs!=null && i < hrefscount; i++) {
-                Element a = (Element)hrefs.item(i);
+            for (int i = 0; hrefs != null && i < hrefscount; i++)
+            {
+                Element a = (Element) hrefs.item(i);
                 // ugly hack to get rid of : in the args - interferes with session handling
                 String href = a.getAttribute("href");
-                if (!href.equals("")) {
-                    if (href.indexOf("?")!=-1) {
+                if (!href.equals(""))
+                {
+                    if (href.indexOf("?") != -1)
+                    {
                         String[] parts = StringUtils.split(href, "\\?", -1);
                         if (parts.length == 1)
                         {
                             parts[0] = StringUtils.replace(parts[0], ":", "%3A");
-                            href = "?"+parts[0];
+                            href = "?" + parts[0];
                         }
                         else
                         {
                             parts[1] = StringUtils.replace(parts[1], ":", "%3A");
-                            href = parts[0]+"?"+parts[1];
+                            href = parts[0] + "?" + parts[1];
                         }
-                        
+
                     }
                     a.setAttribute("href", response.encodeURL(href));
                 }
             }
-            
+
             // now find any submit bits - get all the <form> elements
             NodeList forms = data.getElementsByTagName("form");
             int formscount = forms.getLength();
-            for (int i=0; forms!=null && i < formscount; i++) {
-                Element form = (Element)forms.item(i);
+            for (int i = 0; forms != null && i < formscount; i++)
+            {
+                Element form = (Element) forms.item(i);
                 form.setAttribute("action", response.encodeURL(form.getAttribute("action")));
             }
@@ -686 +874 @@
             // we should only do this for greenstone urls?
         }
-        
+
     }
 
-    synchronized protected int getNextUserId() {
+    synchronized protected int getNextUserId()
+    {
         next_user_id++;
         return next_user_id;
     }
 
-    public void doPost(HttpServletRequest request, HttpServletResponse response)
-    throws ServletException, IOException {
-
-        doGet(request,response);
-        
+    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
+    {
+        doGet(request, response);
     }
 }