Database query j2me including criterias

Question

I am creating an application with J2ME. for connecting with database i am using RecordStore.

so to get a record i need to write as follow:

public boolean SearchRecord(String Rec, int pos )
    {
        String [] data = getRecordData();

        Rec = Rec.substring(0,pos);
        for ( int i = 0 ; i < data.length ; i++ )
        {
            data[i] = data[i].substring(0, pos );
            if ( Rec.toString().trim().equals(data[i].toString().trim()) )
            {
                data = null; // System.gc();
                return true;
            }
        }

        data = null; // System.gc();
        return false;
    }

This is first get all records and traverse through it to search a record. But i have thousands of records and i just need some based on criteria is there any way to resolve this problem ? I do not want to traverse through thousands of records to get ten records.

One more thing i am confused about UI part that LWUIT is better or JSR is better to implement ?

Piper

Open a new question for the UI part. – Guarneri

Answer 1

The code you are talking in the question is method from my answer. I have developed this code about a year ago for searching purpose only. The basic of RMS is a structured version of flat file. You can not fire a query on RMS. There is no in-built method for searching records from RMS. This is the reason that after many r & d i developed the above code.

Detribalize

i have searched a lot and got that answer from your answer. but the issue is that my application takes much time to show 10 records as it has to filter through 10000 records. – Piper

agree, but you have no other option to search from a flat file kind of data structure. – Detribalize

is there any other option of RMS can we use database ? – Piper

for J2ME we have no other option than RMS. – Detribalize

Answer 2

If you are calling SearchRecord a lot you could make String [] data an attribute. This would lead to a smaller version of your method:

public boolean SearchRecord(String rec, int pos )
{
    rec = rec.substring(0, pos).trim();
    for ( int i = 0 ; i < this.data.length ; i++ )
    {
        String comp = this.data[i].substring(0, pos);
        if ( rec.equals(comp.trim()) )
        {
            return true;
        }
    }

    return false;
}

Guarneri

i just dont want to traverse through all records.. I want it to provide criteria like in sql we arite select employee where fname='abc' here we get all record and then find record with first anme i want to get that record only from database – Piper

You can use a RecordFilter when calling RecordStore.enumerateRecords, but, for each comparison, you will have to convert from byte[] to String. – Guarneri