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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
//
static void Manage() throws IOException {
System.out.println("MANAGE");
// 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();
}
//
// Add_CustomerMaster_Records()
//
// This function adds records to table CustomerMaster from an
// array of Strings
//
public static class DATA_RECORD {
// struct members
public String number, zipcode, state, rating, name, address, city;
// struct constructor
public DATA_RECORD(String number, String zipcode, String state, String rating, String name, String address, String city) {
this.number = number;
this.zipcode = zipcode;
this.state = state;
this.rating = rating;
this.name = name;
this.address = address;
this.city = city;
}
};
static void Add_CustomerMaster_Records() throws IOException {
DATA_RECORD[] data = new DATA_RECORD[4];
data[0] = new DATA_RECORD("1000", "92867", "CA", "1", "Bryan Williams", "2999 Regency", "Orange");
data[1] = new DATA_RECORD("1001", "61434", "CT", "1", "Michael Jordan", "13 Main", "Harford");
data[2] = new DATA_RECORD("1002", "73677", "GA", "1", "Joshua Brown", "4356 Cambridge", "Atlanta");
data[3] = new DATA_RECORD("1003", "10034", "MO", "1", "Keyon Dooling", "19771 Park Avenue", "Columbia");
int nRecords = data.length;
Delete_Records(MyRecord);
System.out.println("\tAdd records...");
try {
for (int i = 0; i < nRecords; i++) {
MyRecord.Clear();
// populate record buffer with data
MyRecord.SetFieldAsString(0, data[i].number);
MyRecord.SetFieldAsString(1, data[i].zipcode);
MyRecord.SetFieldAsString(2, data[i].state);
MyRecord.SetFieldAsString(3, data[i].rating);
MyRecord.SetFieldAsString(4, data[i].name);
MyRecord.SetFieldAsString(5, data[i].address);
MyRecord.SetFieldAsString(6, data[i].city);
// add record
MyRecord.Write();
}
} catch (CTException E) {
Handle_Exception(E);
}
}
//
// Delete_Records()
//
// This function deletes all the records in the table
//
static void Delete_Records(CTRecord record) throws IOException {
boolean found;
System.out.println("\tDelete records...");
try {
// enable session-wide lock flag
MySession.Lock(LOCK_MODE.WRITE_BLOCK);
// read first record
found = record.First();
while (found) // while records are found
{
// delete record
record.Delete();
// read next record
found = record.Next();
}
// reset session-wide locks
MySession.Unlock();
} catch (CTException E) {
Handle_Exception(E);
}
}
//
// Display_Records()
//
// This function displays the contents of a table. First() and Next()
// fetch the record. Then each field is parsed and displayed
//
static void Display_Records() throws IOException {
boolean found;
String custnumb;
String custname;
System.out.print("\tDisplay records...");
try {
// read first record
found = MyRecord.First();
while (found) {
custnumb = MyRecord.GetFieldAsString(0);
custname = MyRecord.GetFieldAsString(4);
System.out.println("\n\t" + custnumb + "\t" + custname);
// read next record
found = MyRecord.Next();
}
} catch (CTException E) {
Handle_Exception(E);
}
}
//
// Update_CustomerMaster_Records()
//
// Update one record under locking control to demonstrate the effects
// of locking
//
static void Update_CustomerMaster_Record() throws IOException {
System.out.println("\tUpdate Record...");
try {
// enable session-wide lock flag
MySession.Lock(LOCK_MODE.WRITE_BLOCK);
MyRecord.Clear();
MyRecord.SetFieldAsString(0, "1003");
// find record by customer number
if (MyRecord.Find(FIND_MODE.EQUAL)) {
MyRecord.SetFieldAsString(4, "KEYON DOOLING");
// rewrite record
MyRecord.Write();
System.out.println("\tPress <ENTER> key to unlock");
System.in.read();
}
// reset session-wide locks
MySession.Unlock();
} catch (CTException E) {
Handle_Exception(E);
}
}
