ItemNotFoundException when trying to compute a file path (the request item is absent from configuration)

 Hi I am using RTC Enterprise version 6.0.4 . I am trying to fetch full file paths of all the files in a changeset in this way :

IVersionableHandle filePathHandle = versionableHandle;
currentItem = versionableManager.fetchCompleteState(versionableHandle, monitor);
try {
 while (filePathHandle != null) {
   final String name = currentItem.getName();
   if (name != null & name.length() > 0) {
     filePath = name + File.separator + filePath;
   }
   filePathHandle = currentItem.getParent();
   if (filePathHandle != null) {
     //You have to switch from verManager.fetchCompleteState(versionableHandle, monitor) to
     // iconfig.fetchCompleteItem (versionableHandle, monitor) to avoid null state for folders.
      log.debug("To get the filePath for File:" + currentItem.getName() + " FilePath: " + filePath);
     currentItem = iConfig.fetchCompleteItem(filePathHandle, monitor);
   }
 }
 if (!filePath.isEmpty() && (versionableHandle instanceof IFileItemHandle)) {
   workingFileName = filePath.substring(0, filePath.length() - 1);
 }

IComponentHandle componentHandle = changeset.getComponent();
IConfiguration iConfig = workspaceConnection.configuration(componentHandle);

workspaceManager.findWorkspacesContainingChangeset(changeSet, wsc, Integer.MAX_VALUE, monitor);

</pre>

IConfiguration iConfig = workspaceConnection.configuration(componentHandle);

    </pre>
    <pre style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0); font-family: Menlo; font-size: 9pt;">

I can even get the fileName using : IVersionable.getName() .. but problem is while retrieving full file path. 
    </pre>
    <pre style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0); font-family: Menlo; font-size: 9pt;">

Any use-case when this fileItem won't be present in IConfig ?
    </pre>
    <pre style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0); font-family: Menlo; font-size: 9pt;">

Because as per my understanding if this changeset is present in workSpace means it should be present in IConfig as well ? 
    </pre>
</div>