Significance of sync key for a Sync Bo

Question

Hi,
What is meant by the sync Key in MI Client application. How is it used to identify a particular sync BO instance.
Is it the same as that of the key field selected in the syncbo mapping.
If the syncbo has multiple key fields what would be the sync key in the application
Regards
Raja Sekhar

Answer 1

Hi Raja,
<<<1>>>
Anyway u will not have any difficulty to find out the SyncKey. It is coming as the first field of the SyncBO instance ,whether it is an item instance or header instance.
just go throught this..
For modifying one  syncbo instance ,
in the meRepMeta.xml file corresponding to that SyncBo ,  allowModify="true".This must be satisfied.
For modifying one  syncbo instance , u can do it like described below..
  Here u must need the sync key of the header .u have to find out this sync key using one of the standard methods(first entry  of a row is sync key of that sync bo instance).
Then to modify the header instance .
1) u can use the standard method <b>modifyRowInDB</b> . here the input parameters are SyncBo name , Sync Key , Value and index of the Column. But the limitation of this method is ,if u have more than one field to modify , then u have to use this method inside the loop. In this method , we are explicitely calling the commit() method . So during looping if one of the modification fails for particular sync bo instance , then we have to manually do the rollback for the previous transactions.
  we can change the method like this..
public void modifyHeaderOfSyncBo(String syncBoName,String syncKey,String headerFieldNames[],String  headerFieldValues[])throws SmartSyncException, PersistenceException
SyncBo syncBo = getSyncBoInstance(syncBoName, syncKey);
SmartSyncTransactionManager transactionManager;
          transactionManager = dataFacade.getSmartSyncTransactionManager();
          if (!transactionManager.isTransactionStarted())
               transactionManager.beginTransaction();
          for (int c = 0; c < headerFieldNames.length; c++) {
               setHeaderFieldValue(syncBo, headerFieldNames[c], headerFieldValues[c]);
//Commit the transaction          
transactionManager.commit();
To modify the Item Instance
In two ways
1) If we know the sync key of the header and there is only one item instance.
Here using the header Sync key , we have to find out the SyncBo instance -->> then find out the item instance / instances
-->> then modify the item.
public void  modifyItemOfSyncBo(String syncBoName,String headerSyncKey,String itemName,String itemFieldNames[],String  itemFieldValues[])throws SmartSyncException, PersistenceException
SyncBo syncBo = getSyncBoInstance(syncBoName, headerSyncKey);
Row [] itemRows = getItemInstances(syncBo,itemName);//this is the standard method.
// itemRows[0] is the one and only item instance
SyncBoDescriptor sbd =
   descriptorFacade.getSyncBoDescriptor(syncBoName);
RowDescriptor rd = sbd.getRowDescriptor(itemName);
SmartSyncTransactionManager transactionManager;
          transactionManager = dataFacade.getSmartSyncTransactionManager();
          if (!transactionManager.isTransactionStarted())
               transactionManager.beginTransaction();
          for (int c = 0; c < itemFieldNames.length; c++) {
          FieldDescriptor fdDesc = rd.getFieldDescriptor(itemFieldNames[c]);
                                setItemFieldValue(fdDesc, itemRow[0], itemFieldValues); // this method is given below
          transactionManager.commit();
2) If we know the  Sync key of the item instance.
    Here what u have to do is find out the particular sync bo item instance and then modify as mentioned above.
Here we know the Sync Key of the item instance ,so here we will get the exact item row instance.So after retrieving the item row instance just modify this item row instance with new values as mentioned above.
This method is for setting values in item instance.Just follow this method
     private void setItemFieldValue(FieldDescriptor fd, Row item, Object value)
          throws SmartSyncException, PersistenceException {
          BasisFieldType bft = fd.getFieldType();
          //                 integer oprator
          if (bft == BasisFieldType.N) {
               NumericField nf = item.getNumericField(fd);
               if (nf != null) {
                    BigInteger ii = new BigInteger(value.toString());
                    //                 nf.setValue(ii);
                    item.setFieldValue(fd, ii);
          //                 charactor operator
          if (bft == BasisFieldType.C) {
               CharacterField cf = item.getCharacterField(fd);
               if (cf != null) {
                    //                 cf.setValue(newValues<i><i></i>toString());
                    item.setFieldValue(fd, value);
          //                 decimal operator
          if (bft == BasisFieldType.P) {
               DecimalField df = item.getDecimalField(fd);
               if (df != null) {
                    if (value.equals(""))
                         value = "0";
                    BigDecimal bd = new BigDecimal(value.toString());
                    //                 df.setValue(bd);
                    item.setFieldValue(fd, bd);
          if (bft == BasisFieldType.D) {
               DateField df = item.getDateField(fd);
               if (df != null) {
                    if (value.equals("")) {
                         Date syDatum = new Date(System.currentTimeMillis());
                         value = syDatum.toString();
                    Date dat = Date.valueOf(value.toString());
                    item.setFieldValue(fd, dat);
<<<<<<<<<<<<<<<<
2. How is the syncbo organized in the mobile device. What is the significance of rows?
Does each row represent one instance of syncbo.
>>>>>>>>>>>>>>>>
  Ur understanding is correct. Data is organized in the form of header and item.
  One Header instance can have 0 , one or more item instances.
  I dont know , how exactly that link is maintained in bw HEADER and ITEM instance. Because i could see only this SYNC_KEY field in the instances.
  I think it might be handled by the SmartSync Framework itself.
<<<<<<
For example each work order would be a row in the work order syncbo.
The fields declared in the getlist bapi  wud be part of header and fields in the Getdetail bapi be the items.
>>>>>>
Number of rows returned by the GETLIST BAPI Wrapper actually represents the HEADER instances in the SmartSync.
We may have 0 , one or more ITEM instances for particular HEADER instance.
(During Sync , First GETLIST collects all HEADER instances . Then looping though each HEADER instance , corresponding GETDETAIL is executed).
<<<<<<
if Getdetail bapi consists of fields from different tables, how are these mapped to the item.
>>>>>>
I didnt get ur question exactly.
Anyway... ,,
  For creating ITEM tables for GETDETAIL , we have to DEFINE one structure , which contain the fields from all tables.
This structure is including as a TABLE parameter of ur GETDETAIL Wrapper. And u will be filling values in these fields that are present in ur STRUCTURE which is included as a TABLE param .
  While Creating SncBOs using SyncBO Builder , u are mapping ur required fields. Only these fields are visible in the client device. Depending upon the
  ugage (i meant whether CREATE Wrapper  , MODIFY , DELETE ) , u can create , modify and Delete these instances.
Refer these links also .. I have already given some  sample codes in these forums.... refer these .. In the generated code itself , some null pointer exceptions are not handled.
In this sample code , that is handled..
Re: Regarding modifying Sync BO
Re: Insert 2 Row (related on the same TopRow) in a syncbo
Re: Order child + item structure in a SyncBo
Regards
Kishor Gopinathan