How to use

findAncestorWithClass

method

in

javax.servlet.jsp.tagext.TagSupport

if (this.value != null) {
  EditorAwareTag tag = (EditorAwareTag) TagSupport.findAncestorWithClass(this, EditorAwareTag.class);
  if (tag == null) {
    throw new JspException("TransformTag can only be used within EditorAwareTag (e.g. BindTag)");

if (this.value != null) {
  EditorAwareTag tag = (EditorAwareTag) TagSupport.findAncestorWithClass(this, EditorAwareTag.class);
  if (tag == null) {
    throw new JspException("TransformTag can only be used within EditorAwareTag (e.g. BindTag)");

/**
 * Find parent tag which must implement AttributeContainer.
 * @throws JspException If we can't find an appropriate enclosing tag.
 */
protected PutTagParent findEnclosingPutTagParent() throws JspException {
  try {
    PutTagParent parent =
      (PutTagParent) findAncestorWithClass(this, PutTagParent.class);
    if (parent == null) {
      throw new JspException("Error - tag put : enclosing tag doesn't accept 'put' tag.");
    }
    return parent;
  } catch (ClassCastException ex) {
    throw new JspException("Error - tag put : enclosing tag doesn't accept 'put' tag.");
  }
}

/**
 * Find enclosing parent tag accepting this tag.
 * @throws JspException If we can't find an appropriate enclosing tag.
 */
protected PutListTagParent findEnclosingParent() throws JspException {
  try {
    PutListTagParent parent =
      (PutListTagParent) findAncestorWithClass(this,
        PutListTagParent.class);
        
    if (parent == null) {
      throw new JspException("Error - tag putList : enclosing tag doesn't accept 'putList' tag.");
    }
    
    return parent;
    
  } catch (ClassCastException ex) {
    throw new JspException("Error - tag putList : enclosing tag doesn't accept 'putList' tag.");
  }
}

  /**
   * Find parent tag which must implement AttributeContainer.
   * @throws JspException If we can't find an appropriate enclosing tag.
   */
 protected AddTagParent findEnclosingPutListTagParent() throws JspException {
  try
   {
   AddTagParent parent = (AddTagParent)findAncestorWithClass(this,AddTagParent.class);
   if( parent == null )
    {
    throw new JspException( "Error - tag add : enclosing tag doesn't accept 'add' tag." );
    }
   return parent;
   }
   catch( ClassCastException ex )
   {
   throw new JspException( "Error - tag add : enclosing tag doesn't accept 'add' tag." );
   }
 }
}

public static Node getContext(Tag t) throws JspTagException {
  ForEachTag xt =
  (ForEachTag) TagSupport.findAncestorWithClass(
  t, ForEachTag.class);
  if (xt == null)
    return null;
  else
    return (xt.getContext());
}

public static Node getContext(Tag t) throws JspTagException {
  ForEachTag xt =
  (ForEachTag) TagSupport.findAncestorWithClass(
  t, ForEachTag.class);
  if (xt == null)
    return null;
  else
    return (xt.getContext());
}

public static Node getContext(Tag t) throws JspTagException {
  ForEachTag xt =
  (ForEachTag) TagSupport.findAncestorWithClass(
  t, ForEachTag.class);
  if (xt == null)
    return null;
  else
    return (xt.getContext());
}

public static Node getContext(Tag t) throws JspTagException {
  ForEachTag xt =
  (ForEachTag) TagSupport.findAncestorWithClass(
  t, ForEachTag.class);
  if (xt == null)
    return null;
  else
    return (xt.getContext());
}

public static Node getContext(Tag t) throws JspTagException {
  ForEachTag xt =
  (ForEachTag) TagSupport.findAncestorWithClass(
  t, ForEachTag.class);
  if (xt == null)
    return null;
  else
    return (xt.getContext());
}

/**
 * Processes the <CODE>param</CODE> tag.
 *
 * @return <CODE>SKIP_BODY</CODE>
 */
@Override
public int doStartTag() throws JspException {
  final ParameterizableTag parameterizableTag =
      (ParameterizableTag)
          TagSupport.findAncestorWithClass(this, ParameterizableTag.class);
  if (parameterizableTag == null) {
    throw new JspException(
        "the 'param' Tag must have a parent tag that implements ParameterizableTag");
  }
  if (this.name != null) {
    parameterizableTag.addParameter(this.name, this.value);
  }
  return SKIP_BODY;
}

public int doStartTag() throws JspTagException {
  CacheTag ancestorCacheTag = (CacheTag) TagSupport.findAncestorWithClass(this, CacheTag.class);
  if (ancestorCacheTag == null) {
    throw new JspTagException("GroupsTag cannot be used from outside a CacheTag");
  }
  ancestorCacheTag.addGroups(String.valueOf(groups));
  
  return EVAL_BODY_INCLUDE;
}

public int doStartTag() throws JspTagException {
  CacheTag ancestorCacheTag = (CacheTag) TagSupport.findAncestorWithClass(this, CacheTag.class);
  if (ancestorCacheTag == null) {
    throw new JspTagException("GroupTag cannot be used from outside a CacheTag");
  }
  ancestorCacheTag.addGroup(String.valueOf(group));
  return EVAL_BODY_INCLUDE;
}

  /** {@inheritDoc} */
  @Override
  protected void execute() throws TilesJspException {
    PutAttributeTagParent parent = (PutAttributeTagParent)
      TagSupport.findAncestorWithClass(this, PutAttributeTagParent.class);


    if (parent == null) {
      throw new TilesJspException(
          "Error: no enclosing tag accepts 'putAttribute' tag.");
    }

    parent.processNestedTag(this);
  }
}

/**
 * Executes the processing of this tag, calling its parent tag.
 *
 * @throws TilesJspException If something goes wrong during execution.
 */
protected void execute() throws TilesJspException {
  AddAttributeTagParent parent = (AddAttributeTagParent)
    TagSupport.findAncestorWithClass(this, AddAttributeTagParent.class);
  if (parent == null) {
    throw new TilesJspException(
        "Error: no enclosing tag accepts 'addAttribute' tag.");
  }
  parent.processNestedTag(this);
}

public static Node getContext(Tag t) throws JspTagException {
  ForEachTag xt =
  (ForEachTag) TagSupport.findAncestorWithClass(
  t, ForEachTag.class);
  if (xt == null)
    return newEmptyDocument();
  else
    return (xt.getContext());
}

  /** {@inheritDoc} */
  @Override
  protected void execute() throws TilesJspException {
    PutListAttributeTagParent parent = (PutListAttributeTagParent) TagSupport
        .findAncestorWithClass(this, PutListAttributeTagParent.class);

    if (parent == null) {
      // Try with the old method.
      super.execute();
    }

    parent.processNestedTag(this);
  }
}

  /**
   * The start tag.
   *
   * @throws JspTagException The standard tag exception thrown.
   * @return The standard Tag return.
   */
  public int doStartTag() throws JspTagException {
    CacheTag cacheTag = (CacheTag) TagSupport.findAncestorWithClass(this, CacheTag.class);

    if (cacheTag == null) {
      throw new JspTagException("A UseCached tag must be nested within a Cache tag");
    }

    cacheTag.setUseBody(!use);

    return SKIP_BODY;
  }
}

  public int doAfterBody() throws JspException
  {
    LayoutTag tag = (LayoutTag) TagSupport.findAncestorWithClass(this,
        LayoutTag.class);

    if (tag == null)
    {
      throw new JspException(
          "Sidebar tag must be in an enclosing Layout tag");
    }

    tag.setSidebar(getBodyContent().getString());

    return SKIP_BODY;
  }
}

@Override
public int doEndTag() throws JspException {
  final RenderPortletTag renderPortletTag =
      (RenderPortletTag) TagSupport.findAncestorWithClass(this, RenderPortletTag.class);
  if (this.windowState != null) {
    final WindowState state = PortletUtils.getWindowState(this.windowState);
    renderPortletTag.setParentUrlState(state);
  }
  if (this.portletMode != null) {
    final PortletMode mode = PortletUtils.getPortletMode(this.portletMode);
    renderPortletTag.setParentUrlMode(mode);
  }
  renderPortletTag.setParentUrlParameters(this.parameters);
  return EVAL_PAGE;
}