Blackberry JAVA DEVELOPMENT ENVIRONMENT - - CRYPTOGRAPHIC SMART CARD DRIVER - DEVELOPMENT GUIDE Průvodce řešením problémů stáhnout pdf (Strana 75)

3: Storing data

Use the MIDP record store

Task Steps

Create a record store. >Invoke openRecordStore() and specify true to indicate that the method should create the record store

if the record store does not exist.

RecordStore store = RecordStore.openRecordStore("Contacts", true);

Add a record. >Invoke addRecord().

int id = store.addRecord(_data.getBytes(), 0, _data.length());

Retrieve a record. >Invoke getRecord(int, byte[], int) and provide the following parameters:

• a record ID

• a byte array

• an offset

byte[] data = new byte[store.getRecordSize(id)];

store.getRecord(id, data, 0);

String dataString = new String(data);

Retrieve all records. 1. Invoke openRecordStore().

RecordStore store = RecordStore.openRecordStore("Contacts", false);

2. Invoke enumerateRecords() with the following parameters:

• filter: specifies a RecordFilter object to retrieve a subset of record store records (if null, the

method returns all records)

• comparator: specifies a RecordComparator object to determine the order in which the method

returns the records (if null, the method returns the records in any order)

• keepUpdated: determines if the method keeps the enumeration current with the changes to the

record store

RecordEnumeration e = store.enumerateRecords(null, null, false);

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Blackberry JAVA DEVELOPMENT ENVIRONMENT - - CRYPTOGRAPHIC SMART CARD DRIVER - DEVELOPMENT GUIDE Průvodce řešením problémů Strana 75