UML (Unified Modeling Language) is so general-purpose modeling language that could be used to express any kinds of software-intensive systems. In this reason, using UML for a specific domain or platform is not sufficient, so you may need to define UML Profile.

part of a project saved as a separate file with the extension name .mfj

A fragmen

A model element typically may have multiple corresponding view elements. Model element have its own data such as name, stereotype, type, etc. View element just renders the corresponding model element in a diagram. View elements may exists multiple times in a diagram or different diagrams.

visual geometric symbolic representation of a software model

Diagram

description of any aspect of a software system such as structure, behavior, requirement, and so on

Model or software model

Many users are confusing the difference between diagramming or drawing tool such as Microsoft Visio and modeling tools such StarUML or Rational Software Architect. First you need to understand a diagram is not a model.

If a string is passed as the parameter to $(), jQuery examines the string to see if it looks like HTML (i.e., it starts with <tag ... >). If not, the string is interpreted as a selector expression

This behaves in almost the same way as outlined previously, with a couple of small exceptions. First, the prefix used to name the input elements within the form (hence the key that denotes them in the params hash) is actually derived from the object's class, e.g. params[:post] if the object's class is Post. However, this can be overwritten using the :as option, e.g. -

if @post is an existing record you wish to edit, you can create the form using

a form can be created by passing form_for a string or symbol representing the object we are concerned with:

For fields generated in this way using the FormBuilder, if :person also happens to be the name of an instance variable @person, the default value of the field shown when the form is initially displayed (e.g. in the situation where you are editing an existing record) will be the value of the corresponding attribute of @person.

This means that when the form is submitted, the value entered by the user will be available in the controller as params[:person][:first_name].

The variable f yielded to the block is a FormBuilder object that incorporates the knowledge about the model object represented by :person passed to form_for. Methods defined on the FormBuilder are used to generate fields bound to this model. Thus, for example,

The method can be used in several slightly different ways, depending on how much you wish to rely on Rails to infer automatically from the model how the form should be constructed.

A FormBuilder object is associated with a particular model object and allows you to generate fields associated with the model object.

You don't have to rely on the automated rendering. For example, actions that could result in the rendering of different templates will use the manual rendering methods:

An action may contain only a single render or a single redirect. Attempting to try to do either again will result in a DoubleRenderError:

Redirects are used to move from one action to another.

It's automatically configured.

Action Controller sends content to the user by using one of five rendering methods.

This is useful for objects that are not yet ready to be persisted, such as a Signup object constructed in a multi-paged process, or objects that don't change much and are needed all the time, such as a User object for a system that requires login.

Sessions allow you to store objects in between requests

All request parameters, whether they come from a GET or POST request, or from the URL, are available through the params method which returns a hash

For every request, the router determines the value of the controller and action keys.

These two methods represent the two basic action archetypes used in Action Controllers. Get-and-show and do-and-redirect.

Actions, by default, render a template in the app/views directory corresponding to the name of the controller and action after executing code in the action.

Unlike index, the create action will not render a template. After performing its main purpose (creating a new post), it initiates a redirect instead.

only the ApplicationController in a Rails application inherits from ActionController::Base. All other controllers in turn inherit from ApplicationController

be created with the

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