Cannot use documentViewer (Primefaces Extensions)

Question

I use Primefaces 5.1, Primefaces Extensions 3.0.0 and GlassFish 4.0 in my project and have many problems with pe:documentViewer. My code is:

• in xhtml

  <f:event listener="#{previewComponent.onPrerender}" type="preRenderView"/>
  <p:tab title="#{text['attach.documento']}" class="borderless nopadding">
      <pe:documentViewer value="#{previewComponent.file2}"/>
  </p:tab>
  

• in bean

  public class PreviewComponent extends BasePage implements Serializable {

  private String filePath;
  
  private StreamedContent file2;
  
  //events
  public void onPrerender(ComponentSystemEvent event) {
      try {
          if (this.filePath == null) {
              if (log.isDebugEnabled()) {
                  log.debug("OnPreRender: filePath is null!");
              }
              ByteArrayOutputStream out = new ByteArrayOutputStream();
  
              Document document = new Document();
              PdfWriter.getInstance(document, out);
              document.open();
  
              for (int i = 0; i < 50; i++) {
                  document.add(new Paragraph("Ficheiro não encontrado."));
              }
  
              document.close();
              setFile2(new DefaultStreamedContent(new ByteArrayInputStream(out.toByteArray()), "application/pdf"));
          } else {
              if (log.isDebugEnabled()) {
                  log.debug("OnPreRender: filePath is " + this.filePath);
              }
              String fileName = FilenameUtils.getName(filePath);
              String mimeType = this.getFacesContext().getExternalContext().getMimeType(fileName);
              if (log.isDebugEnabled()) {
                  log.debug("fileName: " + fileName);
                  log.debug("mimeType: " + mimeType);
              }
              setFile2(new DefaultStreamedContent(new FileInputStream(filePath), mimeType));
          }
      } catch (Exception e) {
          if (log.isDebugEnabled()) {
              log.debug("OnPreRender: error is " + e.getMessage());
          }
      }
  }
  
  //GETTERS and SETTERS
  public String getFilePath() {
      return filePath;
  }
  
  public void setFilePath(String filePath) {
      this.filePath = filePath;
  }
  
  public StreamedContent getFile2() {
      return file2;
  }
  
  public void setFile2(StreamedContent file2) {
      this.file2 = file2;
  }
  

  }

And initialy i have the follow error:

SEVERE: Exception during lifecycle processing java.lang.RuntimeException: There is no web component by the name of Faces Servlet here.

After i add this in web.xml:

<servlet-mapping>
    <servlet-name>faces</servlet-name>
    <url-pattern>*.xhtml</url-pattern>
    <url-pattern>*.jsf</url-pattern>
</servlet-mapping>

And after this i have more errors. Why? Give me some answers please :D