java如何在TestNG中合并两个数据提供程序

Question

我已经在excel工作表中创建了数据。我需要两张图纸（即图纸1和图纸2）中的数据

因此，我编写了两个数据提供者，如下所示。我合并了两个数据提供者。但我得到了空指针异常。我不确定它为什么抛出空指针异常

@DataProvider
public  Object[][] getStep1TestData()

{
    Object data1[][]= TestUtil.getTestData(sheet1);
    return data1;
}


@DataProvider
public  Object[][] getStep2TestData()

{
    Object data2[][]= TestUtil.getTestData(sheet2);// ---getting 

空指针异常 返回数据2； }

@DataProvider
public Object mergeData()

{
      List<Object[]> result = Lists.newArrayList();
      result.addAll(Arrays.asList(getStep1TestData()));
      result.addAll(Arrays.asList(getStep2TestData()));// ----getting null pointer exception here
      return result.toArray(new Object[result.size()][]);
}

//@DataProvider
@Test(dataProvider="mergeData")
public void validateStep2Page(String customer, String customertype, String iscontractsigned, String productname,String productamount,String locationname,
        String address1,String address2,String city, String state, String postalcode, String county, String country, 
        String daysofservices, String servicebranchcode, String csvbranchcode, String product, String quantity, 
        String changeorder) throws Exception

{
    salescreatecontractstep1Page.Selectcustomer(customer, customertype, iscontractsigned, productname, productamount);
    salescreatecontractstep2Page.addlocation(locationname, address1, address2, city, state, postalcode, county, country, daysofservices, servicebranchcode, csvbranchcode, product, quantity, changeorder);
}