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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MageLang Institute.
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