com.ibm.jtopenlite.ddm

Interface DDMWriteCallback



  • public interface DDMWriteCallback
    Used by DDMConnection to obtain the input for a write operation from the user in a memory-conscious fashion.

    Order of operations:

    1. DDMConnection.write(file, callback)
    2. --> callback.getNumberOfRecords()
    3. --> begin loop
    4. ------> callback.getRecordData()
    5. ------> callback.getRecordDataOffset()
    6. ------> callback.getNullFieldValues()
    7. ------> Record is written
    8. --> end loop
    • Method Summary

      Methods 
      Modifier and Type Method and Description
      boolean[] getNullFieldValues(DDMCallbackEvent event, int recordIndex)
      Returns the array of null field values, one for each field in the record to be written.
      int getNumberOfRecords(DDMCallbackEvent event)
      Returns the number of records to write, which is how many times the DDMConnection will call getRecordData() for a given write operation.
      byte[] getRecordData(DDMCallbackEvent event, int recordIndex)
      Returns the record data to write.
      int getRecordDataOffset(DDMCallbackEvent event, int recordIndex)
      Returns the offset into the byte array returned by the prior call to getRecordData() so that a single buffer can be used to write multiple records.
  • >
    • Method Detail

      • getNumberOfRecords

        int getNumberOfRecords(DDMCallbackEvent event)
        Returns the number of records to write, which is how many times the DDMConnection will call getRecordData() for a given write operation.
      • getRecordData

        byte[] getRecordData(DDMCallbackEvent event,
                           int recordIndex)
        Returns the record data to write.
      • getRecordDataOffset

        int getRecordDataOffset(DDMCallbackEvent event,
                              int recordIndex)
        Returns the offset into the byte array returned by the prior call to getRecordData() so that a single buffer can be used to write multiple records.
      • getNullFieldValues

        boolean[] getNullFieldValues(DDMCallbackEvent event,
                                   int recordIndex)
        Returns the array of null field values, one for each field in the record to be written. Returning null indicates no fields should be written with a value of null.