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Manage() provides data management functionality for your application and/or process.
Below is the code for Manage():
//
// Manage()
//
// This function performs record adds and updates using locking
//
private static void Manage ()
{
System.out.println("MANAGE");
// delete any existing records
Delete_Records();
// populate the table with data
Add_CustomerMaster_Records();
// display contents of table
Display_Records();
// update a record under locking control
Update_CustomerMaster_Record();
// display again after update and effects of lock
Display_Records();
}
//
// Delete_Records()
//
// This function deletes all the records in the table
//
private static void Delete_Records ()
{
System.out.println("\tDelete records...");
try
{
stmt.executeUpdate("DELETE FROM custmast");
}
catch (SQLException e)
{
Handle_Exception(e);
}
try
{
conn.commit();
}
catch (SQLException e)
{
Handle_Exception(e);
}
}
//
// Add_CustomerMaster_Records()
//
// This function adds records to table CustomerMaster from an
// array of strings
//
private static void Add_CustomerMaster_Records ()
{
System.out.println("\tAdd records...");
String data[] = {
"('1000','92867','CA','1','Bryan Williams','2999 Regency','Orange')",
"('1001','61434','CT','1','Michael Jordan','13 Main','Harford')",
"('1002','73677','GA','1','Joshua Brown','4356 Cambridge','Atlanta')",
"('1003','10034','MO','1','Keyon Dooling','19771 Park Avenue','Columbia')"
};
try
{
// add one record at time to table
for (int i = 0; i < data.length; i++) {
stmt.executeUpdate("INSERT INTO custmast VALUES " + data[i]);
}
}
catch (SQLException e)
{
Handle_Exception(e);
}
try
{
conn.commit();
}
catch (SQLException e)
{
Handle_Exception(e);
}
}
//
// Display_Records()
//
// This function displays the contents of a table.
//
private static void Display_Records ()
{
System.out.print("\tDisplay records...");
try
{
// execute a query statement
ResultSet rs = stmt.executeQuery ("SELECT * FROM custmast");
// fetch and display each individual record
while (rs.next()) {
System.out.println("\n\t\t" + rs.getString(1) + " " + rs.getString(5));
}
rs.close();
}
catch (SQLException e)
{
Handle_Exception(e);
}
}
//
// Update_CustomerMaster_Records()
//
// Update one record under locking control to demonstrate the effects
// of locking
//
private static void Update_CustomerMaster_Record()
{
System.out.println("\tUpdate record...");
try
{
stmt.executeUpdate("UPDATE custmast SET cm_custname = 'KEYON DOOLING' where cm_custnumb = '1003'");
System.out.println("\tPress <ENTER> key to unlock");
System.in.read(new byte[256]);
conn.commit();
}
catch (SQLException e)
{
Handle_Exception(e);
}
catch (Exception e)
{
Handle_Exception(e);
}
}
