title: How to convert NSObject model class to a sub-class of NSManagedObject?
body: <p>I have this simple model class that represent rss article called RSSEntry.</p>
  
  <p>Now I want to start working wit core data with this model class, but I didn't create the project with the 'use core data' checkbox checked.</p>
  
  <p>this is the class:</p>
  
  <pre><code>#import &lt;Foundation/Foundation.h&gt;
  
  @interface FRSSEntry : NSObject{
      NSString *_blogTitle;
      NSString *_articleTitle;
      NSString *_articleUrl;
      NSDate *_articleDate;
      NSString *_articleImageUrl;
      NSString *_content;
  }
  
  @property (copy) NSString *blogTitle;
  @property (copy) NSString *articleTitle;
  @property (copy) NSString *articleUrl;
  @property (copy) NSDate *articleDate;
  @property (copy) NSString *articleImageUrl;
  @property (copy) NSString *content;
  
  - (id)initWithBlogTitle:(NSString*)blogTitle articleTitle:(NSString*)articleTitle articleUrl:(NSString*)articleUrl articleDate:(NSDate*)articleDate articleImageUrl:(NSString *)imageUrl andContent:(NSString *)content;
  
  
  @end
  </code></pre>
  
  <p>the implementations is:</p>
  
  <pre><code>#import "FRSSEntry.h"
  
  @implementation FRSSEntry
  @synthesize blogTitle = _blogTitle;
  @synthesize articleTitle = _articleTitle;
  @synthesize articleUrl = _articleUrl;
  @synthesize articleDate = _articleDate;
  @synthesize articleImageUrl = _articleImageUrl;
  @synthesize content = _content;
  
  - (id)initWithBlogTitle:(NSString*)blogTitle articleTitle:(NSString*)articleTitle articleUrl:(NSString*)articleUrl articleDate:(NSDate*)articleDate articleImageUrl:(NSString *)imageUrl andContent:(NSString *)content
  {
      if ((self = [super init])) {
          _blogTitle = [blogTitle copy];
          _articleTitle = [articleTitle copy];
          _articleUrl = [articleUrl copy];
          _articleDate = [articleDate copy];
          _articleImageUrl = [imageUrl copy];
          _content = [content copy];
      }
      return self;
  }
  @end
  </code></pre>
  
  <p>very simple. Now how do I convert it so I can use it as a core data entity?</p>