Preferred Locale on AppFuse

The solution provided here are based on locale issues on AppFuse JIRA, specifically, APF-141 which is further refined in APF-142.

Here are the steps to change the request-based locale to user-preferred locale, i.e., implement a session-based locale on AppFuse:
1. Add session-scope PREFERRED_LOCALE and optional request scope DEFAULT_LOCALE constants.
2. Use LoginServlet to set locale session. The parameter, locale, is passed from loginForm.jsp, a selected locale from a dropdown for example.

public final class LoginServlet extends HttpServlet {
  ...
  public void execute(HttpServletRequest request, HttpServletResponse response)
  throws IOException, ServletException {
    ...
    request.getSession().setAttribute(Constants.PREFERRED_LOCALE, request.getParameter("locale"));
    ...
  }
}

3. Persist preferredLocale for user in ActionFilter:

public class ActionFilter implements Filter {
  public void doFilter(ServletRequest req, ServletResponse resp,
          FilterChain chain)
         throws IOException, ServletException {
    ...
    if ((username != null) && (user == null)) {
      ...
      String preferredLocale = session.getAttribute(Constants.PREFERRED_LOCALE).toString();
      if (preferredLocale != null) {
        if (preferredLocale  "") {
          if (user.getPreferredLocale()  null) {
                      user.setPreferredLocale(Constants.DEFAULT_LOCALE);
          }
        } else {
                  user.setPreferredLocale(preferredLocale);
        }
      }
    }      
    session.setAttribute(Constants.PREFERRED_LOCALE, user.getPreferredLocale());
  }
}

4. Add locale filter, LocaleFilter:

public class LocaleFilter implements Filter {
  private static final transient Log log = LogFactory.getLog(LocaleFilter.class);
  public void init(FilterConfig filterConfig) {
  }

  public void destroy() {
  }
  public void doFilter(ServletRequest request, ServletResponse response,
                                      FilterChain chain)
           throws IOException, ServletException {
      HttpServletRequest servletRequest = (HttpServletRequest) request;
      HttpSession session = servletRequest.getSession(false);

      if (log.isDebugEnabled()) {
          log.debug(servletRequest.getRequestURL());
      }
      Locale preferredLocale = null;

      if (session!=null){          
          if (session.getAttribute(Constants.PREFERRED_LOCALE) != null) {
              String localeKey = session.getAttribute(Constants.PREFERRED_LOCALE).toString();
              if (localeKey != null) {
                  if (localeKey.equals("")) {
                      String[] keys = Constants.DEFAULT_LOCALE.split("-");
                      preferredLocale = new Locale(keys[0],keys[1]);
                  } else {
                      String[] keys = localeKey.split("-");
                      preferredLocale = new Locale(keys[0],keys[1]);
                  }
              }    
          }
      }
      if (null != preferredLocale
              && !(request instanceof LocaleResponseWrapper)) {
          request = new LocaleResponseWrapper(servletRequest, preferredLocale);
      }

      chain.doFilter(request, response);
   }
}

5. The associated LocaleResponseWrapper is equivalent to LocaleRequestWrapper:

public class LocaleResponseWrapper extends HttpServletRequestWrapper {
  private final Locale preferredLocale;
  private Enumeration locales;

  public LocaleResponseWrapper(HttpServletRequest request, Locale sessionLocale) {
       super(request);
       preferredLocale = sessionLocale;
  }

  public Locale getLocale() {
      if (null != preferredLocale) {
          return preferredLocale;
      } else {
          return super.getLocale();
      }
  }
  public Enumeration getLocales() {
      if (null != preferredLocale) {
          return setLocales();
      } else {
          return super.getLocales();
      }
  }
  private Enumeration setLocales() {
      if (null == locales) {
          List l = Collections.list(super.getLocales());
          l.add(0, preferredLocale);
          locales = Collections.enumeration(l);
      }
      return locales;
  }
} 

6. Put the locale filter in web.xml or appfuse/metadata/web/filters.xml:

<filter>
  <filter-name>localeFilter</filter-name>
  <display-name>Locale Filter</display-name>
  <filter-class>org.appfuse.webapp.filter.LocaleFilter</filter-class>
</filter>

7. Modify JSP’s: add page-scope locale setting:

<fmt:setLocale value="${preferredLocale}" /> 

Now AppFuse is powered by preferred locale! 
¶ 9:41 AM comments/評論(8)

告訴你為什麼程式不 work

為什麼程式不 work？ 我不是跟你說了嗎？

10. 'That's weird...'
9. 'It's never done that before.'
8. 'It worked yesterday.'
7. 'You must have the wrong version.'
6. 'It works, but it hasn't been tested.'
5. 'Somebody must have changed my code.'
4. 'Did you check for a virus?'
3. 'Where were you when the program blew up?'
2. 'Why do you want to do it that way?'

and finally ...

1. 'I thought I fixed that.'

source , link

慚愧，這些藉口我都用盡了，不曉得有否其他可以借用？ 
¶ 7:43 AM comments/評論(0)

AJAX on AppFuse

Steps in setting up DWR on AppFuse:

1. Add DWR jar in /lib/dwr-1.0
2. Add to /lib/lib.properties:

#
# DWR - https://dwr.dev.java.net/ (Direct Web Remoting)
#
dwr.version=1.0
dwr.dir=${lib.dir}/dwr-${dwr.version}
dwr.jar=${dwr.dir}/dwr.jar

3. Add to /properties.xml:

<!-- Web -->
<path id="web.compile.classpath">
 ...
 <pathelement location="${dwr.jar}"/>
</path>

4. Add to /build.xml:

<target name="package-web" depends="compile-web,jsp-2" description="Package WAR">
 ...
 <war destfile="${webapp.dist}/${webapp.war}"
       webxml="${webapp.target}/WEB-INF/web.xml" compress="true">
   ...
   <lib file="${dwr.jar}"/>
 </war>
</target>

5. Add DWR servlet in /metadata/web/servlets.xml:

<!-- dwr servlet -->
<servlet>
 <servlet-name>dwr-invoker</servlet-name>
 <display-name>DWR Servlet</display-name>                
 <servlet-class>uk.ltd.getahead.dwr.DWRServlet</servlet-class>
 <init-param>
   <param-name>debug</param-name>
   <param-value>true</param-value>
 </init-param>
</servlet>

6. Add DWR servlet mapping in /metadata/web/servlet-mappings.xml:

<!-- dwr mapping -->
<servlet-mapping>
 <servlet-name>dwr-invoker</servlet-name>
 <url-pattern>/dwr/*</url-pattern>
</servlet-mapping>

7. Exclude DWR from sitemesh in /web/WEB-INF/classes/decorators.xml:

<excludes>
 <pattern>/dwr/*</pattern>
</excludes>

8. Add DWR configuration, /WEB-INF/dwr.xml:

<dwr>
 <allow>
   <convert converter="bean" match="com.octasoft.fp.*"/>
   <create creator="spring" javascript="userManager">
     <param name="beanName" value="userManager"/>
     <include method="getUser"/>
     <include method="getUsers"/>
   </create>
 </allow>
</dwr>

Here we use DWR provided Spring creator, and utilizes userManager for remoting. Also, we use default-deny policy for the service.

To browse and test DWR-enabled Spring beans: http://server:port/fpweb/dwr/index.html.

Note:
It might be required to delete the existing web.xml in \build\fpweb\WEB-INF\ in order to successfully add in DWR servlet into web.xml.

Use case
Verifying user by username before authentication on loginForm.jsp; on verification, user’s nickname is shown:

<script src="/appfuse/dwr/engine.js" type="text/javascript"></script>   
<script src="/appfuse/dwr/util.js" type="text/javascript"></script>
<script src="/appfuse/dwr/interface/userManager.js" type="text/javascript"></script>
<script>
DWREngine.setErrorHandler(doNothing);
var nickname = "";
function doNothing() {
 return false;
}
function getNickname() {
 if (nickname == "") { 
     userManager.getUser(popUser,document.loginForm.j_username.value);
   document.loginForm.j_password.focus();
   return false;
 } else {
   return validateForm( document.loginForm, false, true, true, false, 1)
 }   
}

var popUser = function(user) {
 if (user == undefined) {
   return false;
 } else {   
   DWRUtil.setValue("nick", "Hello, " + user.nickName);
   nickname = user.nickName;
 }   
}
</script>
<form method="post" name="loginForm" id="loginForm"
      action="<c:url value="/authorize"/>" onsubmit="return getNickname();">
 <div id="nick"></div>
 <input name="j_username" type="text" id="j_username"/>
 <input name="j_password" type="password" id="j_password"/>
</form>

 
¶ 4:07 PM