# Testing Business Components

The view objects that you design perform queries on their underlying entity objects. Often, as a part of your application, you create business logic and validation rules to process the output from view objects and the data values they can accept. By using the Business Component Browser (also called the Tester, for short), you can ensure that your view object's business logic and validation rules are working correctly before you deploy it or make it a part of a larger application.

The Tester lets you test the output of your view objects as soon as you create them; you do not have to create an application to run them. The Tester is an independent utility. It detects the view objects present in an application module or package and creates a default application module to run them. The view objects can either be independent, or in a master-detail relationship defined by a view link.

The Tester helps you ensure that the business logic and validation rules are being applied correctly by letting you insert, update, delete, and query view object data. It accepts changes which meet business logic and validation rule criteria, and returns exceptions for changes that do not. You can also use the Tester to create new view objects or links to query for different output.

You can use the Tester to examine the output of an individual view object or of a master-detail set of view objects defined by a view link. After you open the Tester and connect to a database, it creates a default root application module, then installs your application module as a child of the root. For view objects, the Tester displays the query results. For view links that coordinate the output of two view objects, the Tester displays the query results, with the master-detail relationship constructed for you.

#### To test the business logic tier:

1. In the Workspace view of the Navigator, right-click the application module and choose Test.

   JDeveloper compiles your project.

2. In the Connect dialog, make sure that the connection information is valid, and then click Connect.

   The Tester appears. Its Navigation pane displays all the view objects and view links in the application module. You can display them in the right pane.

   Remember that default view objects and view links were automatically generated based on the database tables and key relationships.

3. Perform the operations you want to try in the Tester:

   - Executing a View Object or Link Query

   - Reexecuting a Query in the Tester

   - Viewing and Changing Called Methods and Values in the Tester

   - Examining Attribute Characteristics in the Tester

   - Examining XML Output in the Tester

   - Examining Diagnostic Information from the Tester

   - Enabling Debug Tracing in the Tester

4. When you are finished testing your program, choose File | Exit to close the Tester.