public static void syncronizeQLI(list <QuoteLineItem> lstQLI){

map<string,string> mapQuoteOppty=new map<string,string>();
string JSONContent=Json.Serialize(lstQLI);
System.debug('##### JSONCONTENT      '+JSONContent);
JSONParser parser =JSON.createParser(JSONContent);
list<string> OpptyLineId=new list<string>();
list<string> QuoteLineId=new list<string>();

System.debug('parser-------->'+parser );

while (parser.nextToken() != null)
{
    if(parser.getCurrentToken()==JSONToken.VALUE_STRING && parser.getCurrentName()=='OpportunityLineItemId__c')
    OpptyLineId.add(parser.getText());

    if(parser.getCurrentToken()==JSONToken.VALUE_STRING && parser.getCurrentName()=='Id')
    QuoteLineId.add(parser.getText());

    parser.nextToken();

    if(parser.getCurrentToken()==JSONToken.VALUE_STRING && parser.getCurrentName()=='OpportunityLineItemId__c')
    OpptyLineId.add(parser.getText());

    if(parser.getCurrentToken()==JSONToken.VALUE_STRING && parser.getCurrentName()=='Id')
    QuoteLineId.add(parser.getText());
}

System.debug('OpptyLineId-------->'+OpptyLineId);
System.debug('QuoteLineId-------->'+QuoteLineId);

integer iCount=0;
for(string strOppLineId : OpptyLineId)
{
    string iQuoteLineId=QuoteLineId[iCount];
    mapQuoteOppty.put(iQuoteLineId,strOppLineId);
    iCount++;
}
System.debug('************ MAP QUOTE OPP            '+mapQuoteOppty);
Set<Id> SetOppId=new Set<Id>();
Set<Id> SetQuoteId=new Set<Id>();
for(QuoteLineItem QLI : lstQLI)
{
    SetQuoteId.add(QLI.QuoteId);
}
List<Quote> Lstquotes =[SELECT id, OpportunityId, isSyncing FROM Quote WHERE isSyncing = true AND Id in :SetQuoteId];
for(Quote Qt:Lstquotes)
{
    SetOppId.add(Qt.OpportunityId);
}

List<OpportunityLineItem> lstOLI=[select Id, OpportunityId,Field1__c,Field2__c from OpportunityLineItem where OpportunityId in:SetOppId];

Map<Id,OpportunityLineItem> MapOLI=new Map<Id,OpportunityLineItem>([select Id,OpportunityId, Field2__c, Field1__c  from OpportunityLineItem where OpportunityId in:SetOppId]);

Map<Id,QuoteLineItem > MapQLI=new map<Id,QuoteLineItem>([Select Id,QuoteId, Field2__c, Field1__c from QuoteLineItem where QuoteId in:SetQuoteId]);

list<OpportunityLineItem> updateQuoteLineItem =new list<OpportunityLineItem >();


for(QuoteLineItem qli:MapQLI.values())
{
system.debug(' -------- QLI.ID         '+qli.id);
system.debug('mapQuoteOppty.get(qli.id) '+mapQuoteOppty.get(qli.id));
       if(mapQuoteOppty.get(qli.id)!=null)
   {
      String OppID = mapQuoteOppty.get(qli.id);
      System.debug('###### OPPID      -----------  '+OppID);
      OpportunityLineItem OLI = MapOLI.get(OppID);
      qli.Field1__c=OLI.Field2__c;
      qli.Field2__c=OLI.Field1__c;

      updateQuoteLineItem.add(OLI);
   }

}
system.debug('UPDATES QUOTE LINE ITEM LIST        '+updateQuoteLineItem);
update updateQuoteLineItem;
}

trigger QuoteLineItemAfterInsert on QuoteLineItem (before insert, after insert){
list<QuoteLineItem> lstQLI = new list <QuoteLineItem>();
for ( QuoteLineItem qli : trigger.new){
    lstQLI.add(qli);
}
system.debug('LIST QLI TRIGGER           '+ lstQLI);
if(lstQLI.size()>0){
    AP001_SyncronazingQLI_OLI.syncronizeQLI(lstQLI);
}
}

while (parser.nextToken() != null)
{
    if(parser.getCurrentToken()==JSONToken.VALUE_STRING && parser.getCurrentName()=='OpportunityLineItemId__c')
    OpptyLineId.add(parser.getText());

    if(parser.getCurrentToken()==JSONToken.VALUE_STRING && parser.getCurrentName()=='Id')
    QuoteLineId.add(parser.getText());

    parser.nextToken();

    if(parser.getCurrentToken()==JSONToken.VALUE_STRING && parser.getCurrentName()=='OpportunityLineItemId__c')
    OpptyLineId.add(parser.getText());

    if(parser.getCurrentToken()==JSONToken.VALUE_STRING && parser.getCurrentName()=='Id')
    QuoteLineId.add(parser.getText());
}

for (QuoteLineItem qli : lstQLI) {

    OpptyLineId.add(qli.OpportunityLineItemId__c);
    QuoteLineId.add(qli.Id);
}

SELECT Id, OpportunityLineItemId FROM QuoteLineItem WHERE QuoteId ='0Q01N00000xxxxxxx' AND OpportunityLineItemId != null