Collaboration diagram

• The collaboration diagram for enterItem is
  
• This creates
  • Sale
  • SalesLineItem
  as needed
• It does not create
  • Post
  • ProductCatalog
  • ProductSpecification

Startup Use Case

• How does the system start up?
• It must initialise various objects that are not otherwise created
• It must establish associations between these objects
• It must start an initial processing action on the Controller objects (e.g. POST)

Startup Use Case for Menu-driven Application

• Create ProductCatalog
• Create POST
• Let POST know about ProductCatalog
• Create Menu
• Let Menu know about POST
• Start Menu processing

Startup Use Case for Application Test

• Create ProductCatalog
• Create POST
• Let POST know about ProductCatalog
• Call methods on POST
• Check state of POST

Create ProductCatalog

• ProductCatalog is a persistent object, with state maintained from one "run" of the application to another
• Let a Database Broker create all persistent objects such as ProductCatalog

CatalogBroker

import java.io.*;

public class CatalogBroker {

    public ProductCatalog getCatalog() throws Exception {
	ProductCatalog catalog = null;
  	FileInputStream fileIn = new FileInputStream("catFile");
	ObjectInputStream objIn = new ObjectInputStream(fileIn);
	Object obj = objIn.readObject();
	objIn.close();
	catalog = (ProductCatalog) obj;
	return catalog;
    }

    /**
     * @pre catalog != null
     */
    public void commit(ProductCatalog catalog) throws Exception {
	FileOutputStream fileOut = new FileOutputStream("catFile");
	ObjectOutputStream objOut = new ObjectOutputStream(fileOut);
	objOut.writeObject(catalog);
	objOut.close();
    }
}

Linking the ProductCatalog and POST

• The POST must know about the catalog
• This can be done by a setCatalog() method
• It can also be done in the constructor

  
        public Post(ProductCatalog catalog) {
            this.catalog = catalog;
        }
        

Starting the Application (Java)

      public class Application {
          public static void main(String[] argv) {
              CatalogBroker broker = new CatalogBroker();
              ProductCatalog catalog = null;
              try {
                  catalog = broker.getCatalog();
              } catch(Exception e) {
                 System.out.println("Can't get catalog " +
                                    e.toString());
                 System.exit(1);
              }

              Post post = new Post(catalog);
              ....
          }
      }
      

Starting the Application (Jacl)

set catBroker [java::new CatalogBroker]
java::try {
    set catalog [$catBroker getCatalog]
} catch {TclException err} {
    puts "Can't get Product Catalog"
    puts $err
}

set post [java::new Post $catalog]
...

Creating an Initial ProductCatalog (Java)

public MakeCatalog {
    static public void main(String[] argv) {
        ProductCatalog catalog = new ProductCatalog();
        catalog.add(123, "descr1");
        catalog.add(234, "descr2");
        catalog.add(345, "descr3");

        CatalogBroker catBroker = new CatalogBroker();
        try {
            catBroker.commit(catalog);
        } catch(Exception e) {
            System.out.println("Couldn't save Product Catalog" +
                               e.toString());
        }
    }
}

Creating an Initial ProductCatalog (Jacl)

package require java

set catalog [java::new ProductCatalog]
$catalog add 123 descr1
$catalog add 234 descr2
$catalog add 345 desrc3

set catBroker [java::new CatalogBroker]
java::try {
    $catBroker commit $catalog
} catch {TclException err} {
    puts "can't save Product Catalog"
    puts $err
}

Miscellaneous Jacl Comments

• The contract for Sale.makeLineItem(spec, qty) includes

  getLastItem().getSpecification().equals(spec)

• This says that the specification object in the new LineItem is the same as the original
• Due to the way variables are handled in Jacl, you need to make the specification object global

  
      set spec1 [java::new ProductSpecification 123 spec1]
  
      test test-1 {makeLineItem boundary case, 1 item} {
          set sale [java::new Sale]
          $sale makeLineItem $spec1 3
          set lastItem [$sale getLastItem]
          set spec [$lastItem getSpecification]
      } $spec1
        

• The contract for Sale.getTotal() includes a summation

  total is the sum of the subtotals for all the
        SalesLineItems

• This cannot be specified as an iContract condition, but it can be tested