Magercise 11 - Help: A JDBC Bean Database Manager

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[Magercise 11 | API Docs | Short Course | Magercises]

Help is available for each task.

Task 1

The first task is to design and implement the DatabaseManager Bean with a no-argument constructor, plus access methods for properties for the typical configuration options and database interactions.

Essential properties would include:

• driver
• url
• user
• password
• sql

Depending on your design, you could implement additional properties for handling the results from queries, and so on--whatever fits your design.

Task 2

Next, design and implement several methods that coordinate option processing with database connection and SQL operations:

Depending on your design, these methods could vary considerably, but would typically include:

• parseUrl()
• connectToDB()
• closeDB()
• executeSql()
• formatResultSetOutput()

Task 3

Next, create a database and load it with data.

The skeleton code files include programs for building and loading a sample database from Chris Date's classic database text; see SuppliesAndParts*.java. Also, DatabaseTool.java is included for independently verifying the operation of your database. Of course, you can build and/or verify the database with your preferred database tools, for example, Cloudscape JBMS or Microsoft Access.

Task 4

Design and implement a mechanism for displaying the data that's returned from a query, update, or general database operation.

Note that the return mechanics for executeQuery(), executeUpdate(), and execute() differ. Minimally, you could display the results of an SQL operation via a read-only property. A better design would include support for targets in which the results of a query are delivered via an event object, for example, DatabaseManagerEvent, which would require a listener interface such as DatabaseManagerListener with a notification method such as queryPerformed().

Task 5

Create a separate test program (or add a main() to DatabaseManager.java) that tests the DatabaseManager Bean.

Implementing a method such as DatabaseManager.printResult() facilitates command-line testing.

Task 6

If your executeSql() and connectToDB() are not no-argument methods with void returns, implement the appropriate control methods for point-and-click connection of command button actions to database operations, so that you can interact with a database from the BeanBox.

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