protected UIComponent createComponent(FacesContext context,
    String newId) throws JspException 
{
        UIComponent component;
        Application application = context.getApplication();
        if (binding != null) {
            component = application.createComponent(binding, context,
                                                    getComponentType());
	    component.setValueExpression("binding", binding);
        } else {
            component = application.createComponent(getComponentType());
        }
        component.setId(newId);
        setProperties(component);
        return component;
}

Create and return a new child component of the type returned by calling getComponentType(). If this UIComponentELTag has a non-null binding attribute, this is done by call Application#createComponent with the ValueExpression created for the binding attribute, and the ValueExpression will be stored on the component. Otherwise, Application#createComponent is called with only the component type. Finally, initialize the components id and other properties.

 protected ELContext getELContext() 
{
	FacesContext fc = getFacesContext();
	ELContext result = null;
	if (null != fc) {
	    result = fc.getELContext();
	}
	return result;
}

Return the ELContext for the FacesContext for this request.

This is a convenience for getFacesContext().getELContext().

 protected boolean hasBinding() 
{
	return null != binding;
}

 public  void release() 
{
	this.binding = null;
        this.rendered = null;
	super.release();
}

Release any resources allocated during the execution of this tag handler.

 public  void setBinding(ValueExpression binding) throws JspException 
{
	this.binding = binding;
}

Set the value expression for our component.

 protected  void setProperties(UIComponent component) 
{
        // The "id" property is explicitly set when components are created
        // so it does not need to be set here
        if (rendered != null) {
            if (rendered.isLiteralText()) {
                try {
                    component.setRendered(Boolean.valueOf(rendered.getExpressionString())
                            .booleanValue());
                } catch (ELException e) {
                    throw new FacesException(e);
                }
            } else {
                component.setValueExpression("rendered", rendered);
            }
        }
        if (getRendererType() != null) {
            component.setRendererType(getRendererType());
        }
}

Override properties and attributes of the specified component, if the corresponding properties of this tag handler instance were explicitly set. This method must be called ONLY if the specified UIComponent was in fact created during the execution of this tag handler instance, and this call will occur BEFORE the UIComponent is added to the view.

Tag subclasses that want to support additional set properties must ensure that the base class setProperties() method is still called. A typical implementation that supports extra properties foo and bar would look something like this:

protected void setProperties(UIComponent component) {
  super.setProperties(component);
  if (foo != null) {
    component.setAttribute("foo", foo);
  }
  if (bar != null) {
    component.setAttribute("bar", bar);
  }
}

The default implementation overrides the following properties:

• rendered - Set if a value for the rendered property is specified for this tag handler instance.
• rendererType - Set if the getRendererType() method returns a non-null value.

 public  void setRendered(ValueExpression rendered) 
{
        this.rendered = rendered;
}

Set an override for the rendered attribute.