anchor.diff:  
   If you do not wish to use the Java EE container default data-source, you can also specify additional connection parameters such as JNDI data-source names, JDBC connection information, and data-source types. Note, however, that this means you will probably need configure your application server to provide this new data-source and/or database connection.
   
  -[code, script]
  +[code, console]
   ----
   [cdbookstore]$ jpa-setup --provider Eclipse Link --dbType POSTGRES --dataSourceName java:comp/DefaultDataSource
   ----
   
   Then, let's create a few fields. Again, one single command end Forge will do its best to simplify our lives :
   
  -[code, script]
  +[code, console]
   ----
   [Book.java]$ jpa-new-field --named title
   ----
   
   This creates an attribute called `title` of type `String` with get/set methods. Notice that Forge has also updated the `toString` method. Let's add more commands with different parameters (remember to press `TAB` to get the parameters) :
   
  -[code, script]
  +[code, console]
   ----
   [Book.java]$ jpa-new-field --named description --length 2000
   [Book.java]$ jpa-new-field --named price --type java.lang.Float
  
positive.code: 
  While "holding" most files, you may inspect them using ls. This also works on REST endpoints. So, if you `cd` `BookEndpoint.java` and execute the command `ls`, this is what you get :
  
  [code, script]
  ----
  [BookEndpoint.java]$ ls
  
  
negative.code: 
  Now that we are in the `Book` entity, we can create a new enum field with the following command : 
  
  [code, console]
  ----
  [Book.java]$ jpa-new-field --named language --type org.cdbookstore.model.Language
  ----
  
  By default a JPA field is of type `String`. With the `--type` parameter we can choose from basic datatypes (`int`, `byte`, `char`…), enum, or from other entities and choosing your cardinality (One-to-One, One-to-Many, Many-to-One, Many-to-Many). So let's create a new `Author` entity and have a Many-to-One relationship with `Book` :
  
  [code, console]
  ----
  [Book.java]$ jpa-new-entity --named Author
  [Author.java]$ jpa-new-field --named firstName
  