The application was developed under Tomcat on a Linux server. MySQL was used as the 

database. The system will also be deployed under the same software components due to the 

low expected load of the application, and the financial limitations that apply to public institutions. 

4.1.2 Overall Architecture 

The Permit System consists of three layers: 

   The user interface, which was implemented using Sun's JavaServer Pages (JSP) 

technology. For presentation, both JSP and servlets are used. 

   The business logic, which consists of a package of Java classes.  

   The database layer, which consists of a set of tables in a MySQL database. 

S tr e e t  O p e n in g   P e r m it   S y s te m

  P r e s e n t a t io n   L a ye r  

B u s in e s s   L a ye r

D a t a b a s e   L a y e r

U s e r  In t e r f a c e

  S e r v le ts

Ja v a   C la s s e s

M y S Q L   D a ta b a s e

    JS P   P a g e s

B r o w s e r

Figure 9: Permit System Architecture 

The first step in developing the Permit System architecture was the design of the database by 

capturing the requirements as attributes and tables in a relational system. Then, an initial 

prototype of the user interface was created that consisted of HTML mock up pages. The Java 

classes comprising the business logic were then developed closely based on the database 

tables and the HTML pages. 

During the architectural process, a strong emphasis was placed on the consistency of the three 

layers. Fields of forms that were developed needed to have a corresponding attribute in a 

database table, and vice versa. Furthermore, a file name, attribute, and variable naming 

convention spanning all three layers was introduced to avoid confusion and to make the names 

easier to memorize. 

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