Manage
The manage step provides data management functionality for your application and/or process.
Below is the code for Manage():
//
// Manage()
//
// Populates table and perform a simple query
//
private static void Manage ()
{
System.out.println("MANAGE");
// populate the tables with data
Add_CustomerMaster_Records();
Add_ItemMaster_Records();
Add_Transactions();
// display the orders and their items
Display_CustomerOrders();
Display_OrderItems();
}
//
// Delete_Tables()
//
// This function removes all existing tables
//
private static void Delete_Tables ()
{
try
{
stmt.executeUpdate("DROP TABLE ordritem");
}
catch (SQLException e)
{
Handle_Exception(e);
}
try
{
stmt.executeUpdate("DROP TABLE custordr");
}
catch (SQLException e)
{
Handle_Exception(e);
}
try
{
stmt.executeUpdate("DROP TABLE custmast");
}
catch (SQLException e)
{
Handle_Exception(e);
}
try
{
stmt.executeUpdate("DROP TABLE itemmast");
}
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 ()
{
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')"
};
System.out.println("\tAdd records in table CustomerMaster...");
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);
}
}
//
// Add_ItemMaster_Records()
//
// This function adds records to table ItemMaster from an
// array of strings
//
private static void Add_ItemMaster_Records ()
{
String data[] = {
"(10,19.95,'1','Hammer')",
"(3, 9.99,'2','Wrench')",
"(4, 16.59,'3','Saw')",
"(1, 3.98,'4','Pliers')"
};
System.out.println("\tAdd records in table ItemMaster...");
try
{
// add one record at time to table
for (int i = 0; i < data.length; i++) {
stmt.executeUpdate("INSERT INTO itemmast VALUES " + data[i]);
}
}
catch (SQLException e)
{
Handle_Exception(e);
}
try
{
conn.commit();
}
catch (SQLException e)
{
Handle_Exception(e);
}
}
//
// Add_Transactions()
//
// Add an Order and associated Items "as a transaction" to their
// respective tables. A transaction is committed or aborted if the
// customer number on the order is confirmed valid. Likewise each
// item in the order is verified to be a valid item.
//
private static void Add_Transactions()
{
int i, j = 0;
String[][] orders = {
{ "09/01/2002", "09/05/2002", "1", "1001" },
{ "09/02/2002", "09/06/2002", "2", "9999" }, // bad customer number
{ "09/22/2002", "09/26/2002", "3", "1003" }
};
String[][] items = {
{ "1", "1", "2", "1" },
{ "1", "2", "1", "2" },
{ "2", "1", "1", "3" },
{ "2", "2", "3", "4" },
{ "3", "1", "2", "3" },
{ "3", "2", "2", "99"} // bad item number
};
System.out.println("\tAdd transaction records...");
for (i = 0; i < orders.length; i++)
{
try
{
// add order record
stmt.executeUpdate("INSERT INTO custordr VALUES (" +
"'" + orders[i][0] + "'," +
"'" + orders[i][1] + "'," +
"'" + orders[i][2] + "'," +
"'" + orders[i][3] + "')");
}
catch (SQLException e)
{
Handle_Exception(e);
}
// process order items
while (items[j][0].compareTo(orders[i][2]) == 0)
{
try
{
// add item record
stmt.executeUpdate("INSERT INTO ordritem VALUES (" +
items[j][1] + "," +
items[j][2] + "," +
"'" + items[j][0] + "'," +
"'" + items[j][3] + "')");
}
catch (SQLException e)
{
Handle_Exception(e);
}
// bump to next item
j++;
// exit the while loop on last item
if (j >= items.length)
break;
}
try
{
conn.commit();
}
catch (SQLException e)
{
Handle_Exception(e);
}
}
}
//
// Display_CustomerOrders()
//
// This function displays the contents of CustomerOrders table.
//
private static void Display_CustomerOrders ()
{
System.out.println("\n\tCustomerOrders Table...");
try
{
// execute a query statement
ResultSet rs = stmt.executeQuery ("SELECT * FROM custordr");
// fetch and display each individual record
while (rs.next()) {
System.out.println("\t " + rs.getString(3) + " " + rs.getString(4));
}
rs.close();
}
catch (SQLException e)
{
Handle_Exception(e);
}
}
//
// Display_OrderItems()
//
// This function displays the contents of OrderItems table.
//
private static void Display_OrderItems ()
{
System.out.println("\n\tOrderItems Table...");
try
{
// execute a query statement
ResultSet rs = stmt.executeQuery ("SELECT * FROM ordritem");
// fetch and display each individual record
while (rs.next()) {
System.out.println("\t " + rs.getString(3) + " " + rs.getString(4));
}
rs.close();
}
catch (SQLException e)
{
Handle_Exception(e);
}
}
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