How to set record id by myself in J2ME

Question

I use RecordStore to store my data.

I know when we store data in RecordStore, it automatically generates a record id for each record.

But how can I set the record id by myself? Or how can I get the record id?

Because I want to use the recordstore.setRecord(..) method to update my recordstore.

But when I use RecordEnumeration to fetch RecordStore and use method nextRecordId(), it just shows odd or even ids. I mean when I have 8 records, it just prints out only odd or even records like

2 4 6 8

My code:

    handleRecord.openRecordStore(handleRecord.getRecordName());
    RecordEnumeration re;
    try {
         int rc = handleRecord.getRecordStore().getNumRecords();
         re = hrs.getRcs().enumerateRecords(null, null, true);

         while(re.hasNextElement()) {
             int rid = re.nextRecordId();
             System.out.println(rid);
         }
    } catch(Exception e) {
        System.out.println(e.toString());
    }

from what you describe it appears like you have a simple error in loop - hopping over records. Please show the code you use to iterate `RecordEnumeration` — gnat, Oct 07 '11 at 14:06

score 3 · Accepted Answer · answered Oct 10 '11 at 09:02

MIDP API doesn't have method to set record id by yourself.

See RecordStore API documentation for explanation how this is supposed to work.

"Records are uniquely identified within a given record store by their recordId, which is an integer value. This recordId is used as the primary key for the records. The first record created in a record store will have recordId equal to one (1). Each subsequent record added to a RecordStore will be assigned a recordId one greater than the record added before it. That is, if two records are added to a record store, and the first has a recordId of 'n', the next will have a recordId of 'n + 1'..."

The code that iterates the store appears OK:

     re = hrs.getRcs().enumerateRecords(null, null, true);
     while(re.hasNextElement()) {
         int rid = re.nextRecordId();
         System.out.println(rid);
     }

if you're getting only odd or even record like 2-4-6... or 1-3-5... printed as a result, first thing to check is whether you somehow removed records that are "missing" - this could be done eg using RecordStore.getVersion method:

"Each time a record store is modified (by addRecord, setRecord, or deleteRecord methods) its version is incremented. This can be used by MIDlets to quickly tell if anything has been modified..."

How to set record id by myself in J2ME

1 Answers1