Test Data Factory

                                            ============step 1 Create test data factory========================
                                  
@isTest
public class TestDataFactory {

    //Account object Test data
    public static list<Account> CreateAccData(Integer NumAcc){
        list<Account> lstAcc = new list<Account>();
        for(Integer i=0; i<NumAcc; i++){
            Account acc = new Account();
            acc.Name='TestDataFactoryAccount'+i;
            acc.Description='TestDataFactoryAccount'+i+'Description';
            lstAcc.add(acc);
            upsert lstAcc;
            system.debug('@@@@ Test Data Factory Account: '+lstAcc);
        }
        return lstAcc;
    }
    
    //Lead Object Test Data
    public static list<Lead> CreateLeadData(Integer NumLead){
        list<Lead> lstLe = new list<Lead>();
        try{
            for(Integer i=0; i<=NumLead; i++){
                Lead le = new Lead();
                le.LastName='TestDataFacLead'+i;
                le.Company='TestDataLe'+i+'C';
                le.Status='Working - Contacted';
                le.Fax='10101010';
                lstLe.add(le);
                upsert lstLe;
            }
        }catch(exception ex){
            
        }
        return lstLe;
    }
    
    //Opportunity Object Test Data
    public static list<Opportunity> CreateOppData(Integer NumOpp){
        list<Opportunity> lstOpp= new list<Opportunity>();
        
        for(Integer i=0; i<=NumOpp; i++){
            Opportunity opp = new Opportunity();
            opp.Name='TestDataFacOpp'+i;
            opp.StageName='Qualification';
            opp.CloseDate=system.today();
            opp.Multi_currecy__c='(USD 32,11.90)';
            lstOpp.add(opp);
            upsert lstOpp;
        }
        return lstOpp;
    }
}


                                             ==========step 2      test class======================
                                                          a. For apex batch class
   
   @isTest
public class Test_BatchOpportunityCurrency {

    @isTest
    public static void TestMethod1(){
        
        list<Opportunity> lstOpp = new list<Opportunity>();
        //Calling Test data factory's method to get data created in the class
        lstOpp=TestDataFactory.CreateOppData(10);
        
        test.startTest();
        BatchOpportunityCurrency btOpCu= new BatchOpportunityCurrency();
        Database.executebatch(btOpCu); 
        test.stopTest();
    }
}