java 从excel读取时出现空指针异常？
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Null Pointer Exception while reading from excel?
提问by Ron
public class ExecuteTest {
@Test
public void testLogin() throws Exception {
// TODO Auto-generated method stub
`WebDriver webdriver = new FirefoxDriver();
ReadExcelFile file = new ReadExcelFile();
ReadObject object = new ReadObject();
Properties allObjects = object.getObjectRepository();
UIOperation operation = new UIOperation(webdriver);
//Read keyword sheet
Sheet RDSheet = file.readExcel(System.getProperty("user.dir")+"\","TestCase.xlsx" , "KeywordFramework");
//Find number of rows in excel file
int rowCount = //Loop over all the rows RDSheet.getLastRowNum()-RDSheet.getFirstRowNum();
//Create a loop over all the rows of excel file to read it
for (int i = 1; i < rowCount+1; i++) {
Row row = RDSheet.getRow(i);
//Check if the first cell contain a value, if yes, That means it is the new testcase name
if(row.getCell(0).toString().length()==0){
//Print testcase detail on console
System.out.println(row.getCell(1).toString()+"----"+ row.getCell(2).toString()+"----"+
row.getCell(3).toString()+"----"+ row.getCell(4).toString());
//Call perform function to perform operation on UI
operation.perform(allObjects, row.getCell(1).toString(), row.getCell(2).toString(),
row.getCell(3).toString(), row.getCell(4).toString());
}
else{
//Print the new testcase name when it started
System.out.println("New Testcase->"+row.getCell(0).toString() +" Started");
}
}
}
}
getting null pointer exception when first cell is empty. I have searched many blogs but couldn't find any solution can anyone please help me with code.
当第一个单元格为空时获取空指针异常。我搜索了很多博客，但找不到任何解决方案，任何人都可以帮助我编写代码。
回答by Naman Gala
Make sure you add a null check before using toString()method otherwise you will get NPEif the value is null.
确保在使用toString()方法之前添加空检查，否则NPE如果值为null.
if (row.getCell(0) != null) {
row.getCell(0).toString() //in this case you are trying to call toString on null value.
}
Refer this SO question
参考这个 SO question
回答by Uma Kanth
for every .toString()add a " "+ x.toString()to it, so that the value doesnt become a null.
`
为每个.toString()添加一个" "+ x.toString()，以便该值不会变为空值。`
for (int i = 1; i < rowCount+1; i++) {
Row row = RDSheet.getRow(i);
//Check if the first cell contain a value, if yes, That means it is the new testcase name
if((row.getCell(0)+"").toString().length()==0){
//Print testcase detail on console
System.out.println((row.getCell(1)+"").toString()+"----"+ (row.getCell(2)+"").toString()+"----"+
(row.getCell(3)+"").toString()+"----"+ (row.getCell(4)+"").toString());
//Call perform function to perform operation on UI
//your operations
}
else{
//Print the new testcase name when it started
System.out.println("New Testcase->"+row.getCell(0).toString() +" Started");
}
}
`
回答by KiranVegi
try below Code its working fine for me, we cannot define length of a Null
试试下面的代码，它对我来说工作正常，我们无法定义 Null 的长度
if(row.getCell(0)==null){
//Print testcase detail on console
//System.out.println("testing");
System.out.println(row.getCell(1)+"----"+ row.getCell(2)+"----"+
row.getCell(3)+"----"+ row.getCell(4));
//Call perform function to perform operation on UI
try{
operation.perform(allObjects, row.getCell(1)==null?"Not a Valid KeyWord":row.getCell(1).toString(),
row.getCell(2)==null?null:row.getCell(2).toString(),
row.getCell(3)==null?null:row.getCell(3).toString(),
row.getCell(4)==null?null:row.getCell(4).toString());
}catch(Exception e)
{
//will print Error Row and break the flow
System.out.println(i);
System.out.println(e);
break;
}
}
else{
//Print the new testcase name when it started
System.out.println("New Testcase->"+row.getCell(0) +" Started");
}
}
