Основы портлетов

package ru.habrahabr.rssportlet;

import java.io.*;
import java.util.*;
import javax.portlet.*;

public class HabraRssPortlet extends GenericPortlet {

  public static final String JSP_FOLDER    = "/_HabraRssPortlet/jsp/";
  public static final String VIEW_JSP     = "HabraRssPortletView";
  public static final String EDIT_JSP     = "HabraRssPortletEdit";
  public static final String HELP_JSP     = "HabraRssPortletHelp";
  public static final String CONFIG_JSP    = "HabraRssPortletConfig";
  public static final String RSS_LINKS    = "rssLinks";
  public static final String UPDATE_FREQUENCY = "updateFrequency";
  public static final String ITEM_QUANTITY  = "itemQuantity";
  public static final String NEW_RSS_LINK   = "newRssLink";
  public static final String ADD_NEW_RSS_LINK = "addNewRssLink";
  public static final String DELETE_RSS_LINK = "deleteRssLink";
  public static final String RSS_LINKS_LIST  = "rssLinksList";
  public static final String FREQUENCY     = "frequency";
  public static final String QUANTITY     = "quantity";
  public static final String SET_FREQUENCY  = "setFrequency";
  public static final String SET_QUANTITY   = "setQuantity";
  public static final String ERROR_MESSAGE  = "errorMessage";
  public static final String UPDATE_FEEDS   = "updateFeeds";
  public static final String EDIT_BACK     = "editBack";

  private static HashMap rssMap    = new HashMap();
  private static HashMap updateTimeMap = new HashMap();

  public void doView(RenderRequest request, RenderResponse response)throws PortletException, IOException {
    response.setContentType(request.getResponseContentType());
    PortletPreferences preferences = request.getPreferences();
    
    if (!rssMap.containsKey(request.getUserPrincipal().getName())){
      rssMap.put(request.getUserPrincipal().getName(), new ArrayList());
      updateTimeMap.put(request.getUserPrincipal().getName(), new Long(0));
      
    }
        
    if (RssUtil.checkUpdateTime(getLastUpdateTime(request), preferences)) {
      ArrayList rssItems = (ArrayList)rssMap.get(request.getUserPrincipal().getName());
      rssItems.clear();
      rssItems = RssUtil.updateRssFeeds(preferences);
      System.out.println("News for user " + request.getUserPrincipal().getName() + " updated!");
      rssMap.put(request.getUserPrincipal().getName(), rssItems);
      setLastUpdateTime(request);
      
    }
        
    int interval = Integer.parseInt(preferences.getValue(UPDATE_FREQUENCY, "60"));
    System.out.println("Time befor update (in seconds) = " + ((interval * 60) - ((System.currentTimeMillis() - getLastUpdateTime(request).longValue()) / 1000 )));
    
    request.setAttribute("rssMap", rssMap.get(request.getUserPrincipal().getName()));
    PortletRequestDispatcher rd = getPortletContext().getRequestDispatcher(getJspFilePath(request, VIEW_JSP));
    rd.include(request, response);
  }

  public void doEdit(RenderRequest request, RenderResponse response)
      throws PortletException, IOException {
    response.setContentType(request.getResponseContentType());
    PortletRequestDispatcher rd = getPortletContext().getRequestDispatcher(
        getJspFilePath(request, EDIT_JSP));
    rd.include(request, response);
  }

  protected void doHelp(RenderRequest request, RenderResponse response)
      throws PortletException, IOException {
    response.setContentType(request.getResponseContentType());
    PortletRequestDispatcher rd = getPortletContext().getRequestDispatcher(getJspFilePath(request, HELP_JSP));
    rd.include(request, response);
  }

  public void processAction(ActionRequest request, ActionResponse response)
      throws PortletException, java.io.IOException {
    PortletPreferences preferences = request.getPreferences();

    if (request.getParameter(ADD_NEW_RSS_LINK) != null) {
      if (request.getParameter(NEW_RSS_LINK).trim().length() > 0) {
        String[] links = (String[]) preferences.getValues(HabraRssPortlet.RSS_LINKS, null);
        String newLink = request.getParameter(NEW_RSS_LINK);
        preferences.setValues(RSS_LINKS, addToArray(links, newLink));
        preferences.store();
        System.out.println(">>>>>>>>>>>>>>>> New rss link added " + newLink);
      } else {
        response.setRenderParameter(ERROR_MESSAGE, "Link must be not empty!");
      }
    }

    if (request.getParameter(DELETE_RSS_LINK) != null) {
      if (request.getParameter(RSS_LINKS_LIST) != null
          && request.getParameter(RSS_LINKS_LIST).trim().length() > 0 ) {
        String[] links = (String[]) preferences.getValues(
            HabraRssPortlet.RSS_LINKS, null);
        String deletedLink = request.getParameter(RSS_LINKS_LIST);
        if (isFound(links, deletedLink)) {
          preferences.setValues(RSS_LINKS, deleteFromArray(links, deletedLink));
          preferences.store();
          System.out.println(">>>>>>>>>>>>>>>> Rss link deleted " + deletedLink);
        }
      } else {
        response.setRenderParameter(ERROR_MESSAGE, "Choose a link!");
      }
    }

    if (request.getParameter(SET_FREQUENCY) != null) {
      if (request.getParameter(FREQUENCY).trim().length() > 0
          && isDigit(request.getParameter(FREQUENCY))) {
        String frequency = request.getParameter(FREQUENCY);
        preferences.setValue(UPDATE_FREQUENCY, frequency);
        preferences.store();
        System.out.println(">>>>>>>>>>>>>>>> Frequency updated " + frequency);
      } else {
        response.setRenderParameter(ERROR_MESSAGE, "Set valid frequency!");
      }
    }

    if (request.getParameter(SET_QUANTITY) != null) {
      if (request.getParameter(QUANTITY).trim().length() > 0
          && isDigit(request.getParameter(QUANTITY))) {
        String quantity = request.getParameter(QUANTITY);
        preferences.setValue(ITEM_QUANTITY, quantity);
        preferences.store();
        System.out.println(">>>>>>>>>>>>>>>> Quantity updated " + quantity);
      } else {
        response.setRenderParameter(ERROR_MESSAGE, "Set valid quantity!");
      }
    }

    if (request.getParameter(UPDATE_FEEDS) != null) {
      ArrayList rssItems = (ArrayList)rssMap.get(request.getUserPrincipal().getName());
      rssItems.clear();
      rssItems = RssUtil.updateRssFeeds(preferences);
      System.out.println("News fo user " + request.getUserPrincipal().getName() + " updated!");
      rssMap.put(request.getUserPrincipal().getName(), rssItems);
      setLastUpdateTime(request);
    }

    if (request.getParameter(EDIT_BACK) != null) {
      response.setPortletMode(PortletMode.VIEW);
    }
    
    

  }

  private static String getJspFilePath(RenderRequest request, String jspFile) {
    String markup = request.getProperty("wps.markup");
    if (markup == null)
      markup = getMarkup(request.getResponseContentType());
    return JSP_FOLDER + markup + "/" + jspFile + "."
        + getJspExtension(markup);
  }

  private static String getMarkup(String contentType) {
    if ("text/vnd.wap.wml".equals(contentType))
      return "wml";
    else
      return "html";
  }

  private static String getJspExtension(String markupName) {
    return "jsp";
  }

  private static String[] addToArray(String[] array, String s) {
    String[] ans = new String[array.length + 1];
    System.arraycopy(array, 0, ans, 0, array.length);
    ans[ans.length - 1] = s;
    return ans;
  }

  private static String[] deleteFromArray(String[] array, String s) {
    String[] ans = new String[array.length - 1];
    int addIndex = 0;
    for (int i = 0; i < array.length; i++) {
      if (array[i].equals(s)) {
        addIndex++;
        continue;
      }
      ans[i - addIndex] = array[i];
    }
    return ans;
  }

  private static boolean isFound(String[] array, String s) {
    boolean found = false;
    for (int i = 0; i < array.length; i++) {
      if (array[i].equals(s)) {
        found = true;
        break;
      }
    }
    return found;
  }

  private static boolean isDigit(String s) {
    char[] array = s.toCharArray();
    for (int i = 0; i < array.length; i++) {
      if (!Character.isDigit(array[i])) {
        return false;
      }
    }
    return true;
  }
  
  private static Long getLastUpdateTime(PortletRequest request){
    return (Long)updateTimeMap.get(request.getUserPrincipal().getName());
  }
  
  private static void setLastUpdateTime(PortletRequest request){
    updateTimeMap.put(request.getUserPrincipal().getName(), new Long(System.currentTimeMillis()));
  }
  
  
}

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