IllegalStateException: Client-id : ... is duplicated in the faces tree

[Roel Verwinkel]

Hi,

I'm facing a problem using a datatable component. I can call the view twice without a problem, but the third time I get a IllegalStateException: Client-id : ... is duplicated in the faces tree. Before the exception occurs Hibernate shows a query for populating the datatable, so it's probably a rendering issue.

It's probably something stupid I'm overlooking, but I'm crushing my brains for some hours now on it. Any Ideas?

Kind regards,

Roel


Stacktrace:

java.lang.IllegalStateException: Client-id : j_id40 is duplicated in the faces tree. Component : j_id32:dt1:j_id40, path: {Component-Path : [Class: javax.faces.component.UIViewRoot,ViewId: /pages/userList.xhtml][Class: javax.faces.component.html.HtmlForm,Id: j_id32][Class: javax.faces.component.html.HtmlDataTable,Id: dt1][Class: javax.faces.component.UIColumn,Id: j_id38][Class: javax.faces.component.html.HtmlOutputText,Id: j_id40]}
        at org.apache.myfaces.application.jsp.JspStateManagerImpl.checkForDuplicateIds(JspStateManagerImpl.java:419)
        at org.apache.myfaces.application.jsp.JspStateManagerImpl.checkForDuplicateIds(JspStateManagerImpl.java:431)
        at org.apache.myfaces.application.jsp.JspStateManagerImpl.checkForDuplicateIds(JspStateManagerImpl.java:431)
        at org.apache.myfaces.application.jsp.JspStateManagerImpl.checkForDuplicateIds(JspStateManagerImpl.java:431)
        at org.apache.myfaces.application.jsp.JspStateManagerImpl.checkForDuplicateIds(JspStateManagerImpl.java:431)
        at org.apache.myfaces.application.jsp.JspStateManagerImpl.saveSerializedView(JspStateManagerImpl.java:372)
        at org.springframework.faces.webflow.FlowViewStateManager.saveSerializedView(FlowViewStateManager.java:129)
        at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:615)
        at org.apache.myfaces.lifecycle.RenderResponseExecutor.execute(RenderResponseExecutor.java:41)
        at org.apache.myfaces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:140)
        at javax.faces.webapp.FacesServlet.service(FacesServlet.java:155)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
        at org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:301)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:433)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
        at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
        at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
        at java.lang.Thread.run(Thread.java:619)

JSF-view (stripped):

...
<h:dataTable id="dt1" binding="#{userlist.dataTable}"
 value="#{userlist.users}" var="xuser" bgcolor="#F1F1F1" cellpadding="5" 
cellspacing="3" first="0" rows="4" dir="LTR" frame="hsides" rules="all" summary="These are all active users">
  <h:column>
    <f:facet name="header">
      <h:outputText value="id" />
    </f:facet>
    <h:outputText value="#{xuser.id}"></h:outputText>
  </h:column>
  <h:column>
    <f:facet name="header">
      <h:outputText value="name" />
    </f:facet>
    <h:outputText value="#{xuser.name}"></h:outputText>
  </h:column>
</h:dataTable>
...

faces-config.xml:

...
<managed-bean>
	<managed-bean-name>userlist</managed-bean-name>
	<managed-bean-class>com.xxx.web.internal.beans.UserListPageBean</managed-bean-class>
	<managed-bean-scope>request</managed-bean-scope>
</managed-bean>
...

UserListPageBean (removed getters/setters/imports):

public class UserListPageBean extends BasePageBean  {

    private UserDAO userDAO;
    private HtmlDataTable dataTable;
    private User dataItem = new User();
    private HtmlInputHidden dataItemId = new HtmlInputHidden();
    private HtmlInputHidden addCount = new HtmlInputHidden();
    private List<User> userList;

    private static final Logger log = LoggerFactory.getLogger(UserListPageBean.class);  
	
    public UserListPageBean() {
    }

    public List<User> getUsers() {
        if (userDAO != null) {
            loadUserList();
        }
        return this.userList;
    }

    public String addNewUser() {

        userList.add(new User());
        addCount.setValue(((Integer) addCount.getValue()) + 1);

        return null; 
    }

    private void loadUserList() {

        try {
            userList = userDAO.all();
        } catch (DataException e) {
            e.printStackTrace();
        }

        for (int i = 0; i < (Integer) addCount.getValue(); i++) {
            userList.add(new User());
        }
    }

    public List<User> getUserList() {
        if (userList == null && userDAO != null) {
            loadUserList(); 
        }
        return userList;
    }
}

The userDAO is injected by Spring:

    <bean id="userlist" class="com.xxx.web.internal.beans.UserListPageBean" scope="request">
       <property name="userDAO"><ref bean="userDAO"></ref></property>
    </bean>

[Tim Holloway]

You get thus typically when updating a Faces view when the underlying JSF has been changed, so most commonly when you're tweaking stuff in development. Usually a complete page refresh will flush it out (meaning go to some other page, then request the offending page to be built from scratch, not via "back" or redisplay).

One thing that can help is to be generous when assigning id attributes on components. I've found that placing "id=" on forms and input controls is a general all-around boon.