Cannot remove directory: File exists

I was trying to remove a directory and got error: "cannot remove directory 'logs/': File exists"

$chmod -R 777 logs/
$rm -rf logs/
$rm: cannot remove directory 'logs/': File exists

Checked the logs folder content and found out that there was .nfs*** file in this, when I manually deleted this file, it was recreated immediately and the timestamp of the file was not current, it was same of which I just deleted.

$ls -lrta
total 20K
drwxrwxrwx 3 test vishnu 4.0K May  3 03:27 ..
-rwxrwxr-x 1 test vishnu  11K May  3 03:27 .nfs29682
drwxrwxr-x 2 test vishnu 4.0K Jun  4 23:17 .

To solve this issue, we need to find out which process is using this file and delete that process.

$/usr/sbin/fuser -u logs/.*
logs/.:    
logs/..:    
logs/.nfs29682:     23142m(test)

23142 is the process which is using this directory, we need to kill it.

kill -9 23142

now delete the directory, it will be deleted successfully.

$rm -rf logs/
$

Selenium: Check if Selenium Server is running

If you want to check whether selenium server is running or not, hit the url "http://host:port/selenium-server/driver/?cmd=testComplete", If response is returned that means, server is running on the given host:port. Here is the Java code for this:

import java.net.HttpURLConnection;
import java.net.URL;

public static boolean isSeleniumServerRunning(String host, int port) 
  {
   try {
    String baseUrl = "http://" + host + ":" + port;
    System.out.println("Checking selenium server status [" + baseUrl + "]");
    URL url = new URL(baseUrl + "/selenium-server/driver/?cmd=testComplete");
    HttpURLConnection connection = (HttpURLConnection) url.openConnection();
    
    if(connection.getResponseCode() == HttpURLConnection.HTTP_OK)
     return true;
  } catch (Exception e) {
   System.err.println("Could not check selenium server status: " + e.getMessage());
   e.printStackTrace();
  }   
  return false;
  }

Java: Copy Directory structure

Here is the code for copying a directory structure

 public static void copyFolder(String srcFile, String destFile) throws IOException
 {
  File src = new File(srcFile);
  File dest = new File(destFile);
  
  if(!src.exists())
  {
   System.out.println("Source folder do not exists [" + srcFile + "]");
   return;
  }
  
  if(src.isDirectory())
  {
    //if directory not exists, create it
    if(!dest.exists())
    {
       dest.mkdir();
    }

    //list all the directory contents
    String files[] = src.list();

    for (String file : files) 
    {
     
     //construct the src and dest file structure
     String sourceFile = src.getAbsolutePath() + File.separator + file;
     String destinationFile = dest.getAbsolutePath() + File.separator + file;
     
     //recursive copy
     copyFolder(sourceFile, destinationFile);    }
  }
  else
  {
    //if file, then copy it
    //Use bytes stream to support all file types
    InputStream in = new FileInputStream(src);
          OutputStream out = new FileOutputStream(dest); 

          byte[] buffer = new byte[1024];

          int length;
          //copy the file content in bytes 
          while ((length = in.read(buffer)) > 0){
          out.write(buffer, 0, length);
          }

          in.close();
          out.close();
  }
 }

Java: Comparing Arrays

Want to compare arrays of which item may not be in same order. Here is the solution:

public static boolean compareArrays(String[] actual, String[] expected)
    {
        if(actual == null || expected == null)
            return false;
        
        Arrays.sort(actual);
        Arrays.sort(expected);
        
        if(Arrays.equals(actual, expected))
            return true;
        else
            return false;
    }

GNU Screen: Useful tips

Here are the useful trick for GNU screen:

1. Give access to other users on the screen:

  - Let say screen "test" is running on host 15.25.125.148 with user "xyz"
  - run command "Ctrl a :"
  - type "multiuser on" to enable multiuser mode
  - type "acladd <unix username>" (to whom you want to give access)
  - type "aclchg <args>" to change permissions on the screen for that user
  - Now the user will login on that host via command "ssh user@15.25.125.148"
  - attach to screen with command "screen -x xyz/test"

2. Changing session name of the running screen

The default session name created by the screen command is constructed from the tty and host names, which isn't very intuitive. To change this session name, run this command on your screen session

Ctrl a :sessionname newSessionName

3. Send a command to a window in a running screen session from the commandline 

screen -x <screen session name> -p <window number or name> -X stuff '<command>\012'

4. Create screen session with commands running

- First, create  .screenrc_test with following contents where you specify your tabbed sessions and commands

startup_message off
vbell off
caption always "%{= bb}%{+b w}%n %h %=%t %c"
hardstatus alwayslastline "%-Lw%{= BW}%50>%n%f* %t%{-}%+Lw%<"
activity "Activity in %t(%n)"
deflogin on
shell -/bin/bash

screen -t TAB1
stuff "cd $HOME && ls -1rt | tail -1 | xargs tail -f  \012"
screen -t TAB2
stuff "cd $HOME && top  \012"

- Run screen -S test -c .screenrc_test

5. Starting screen and detach automatically

screen -S test -dm -c .screenrc_test

Javascript: expand/collapse functionality in a web page

Here is the script to implement expand/collapse functionality in a web page.

Javascript:

function toggle(showHideDiv, switchImgTag) 
{
        var elem = document.getElementById(showHideDiv);
        var imageElem = document.getElementById(switchImgTag);
        if(elem.style.display == "block") {
                elem.style.display = "none";
    imageElem.innerHTML = '';
        }
        else {
                elem.style.display = "block";
                imageElem.innerHTML = '';
        }
}

function Collapse(showHideDiv, switchImgTag) 
{
        var elem = document.getElementById(showHideDiv);
        var imageElem = document.getElementById(switchImgTag);
        
  elem.style.display = "none";
  imageElem.innerHTML = '';
}

function Expand(showHideDiv, switchImgTag) 
{
        var elem = document.getElementById(showHideDiv);
        var imageElem = document.getElementById(switchImgTag);
        
  elem.style.display = "block";
        imageElem.innerHTML = '';
}

function ExpandAll()
{
  var elements = document.getElementsByTagName("a");
  for (var i = 0; i < elements.length; i++) 
  {
      var myname = elements[i].getAttribute("id");
    if(myname != null)
    {
       if(myname.substr(0, 4) == "img-")
     {
      var linkid = myname.substr(4);
      Expand("div-"+ linkid, "img-"+linkid);
     }
    }
  }
  document.getElementById('expand-all').style.display='none';
  document.getElementById('collapse-all').style.display='block';
}

function CollapseAll()
{
  var elements = document.getElementsByTagName("a");
  for (var i = 0; i < elements.length; i++) 
  {
      var myname = elements[i].getAttribute("id");
    if(myname != null)
    {
       if(myname.substr(0, 4) == "img-")
     {
      var linkid = myname.substr(4);
      Collapse("div-"+ linkid, "img-"+linkid);
     }
    }
  }
  document.getElementById('expand-all').style.display='block';
  document.getElementById('collapse-all').style.display='none';
}

Web Page:

Expand All 

Collapse All



Test1



TestID
Description
Actual
Expected
Time Taken
Result
Screen-Shot


Test-01
Test 01
PASS
PASS
 1 sec
Pass
None


Test-01
Test 02
PASS
FAIL
 5 sec
Fail
Click me










Test2



TestID
Description
Actual
Expected
Time Taken
Result
Screen-Shot


Test-01
Test 03
PASS
PASS
 1 sec
Pass
None


Test-01
Test 04
PASS
PASS
 2 sec
Pass
None


Test-01
Test 05
PASS
PASS
 3 sec
Pass
None

Stylesheet:

body, table {
    font-family: Verdana, Arial, sans-serif;
    font-size: 12;
}

table {
    border-collapse: collapse;
    border: 1px solid #ccc;
}

th, td {
    padding-left: 0.3em;
    padding-right: 0.3em;
}

a {
    text-decoration: none;
}

.title {
    font-style: italic;
}

.selected {
    background-color: #ffffcc;
}

.status_done {
    background-color: #eeffee;
}

.status_passed {
    background-color: #00FF00;
}

.status_failed {
    background-color: #FF0000;
}

.status_notrun {
    background-color: #FFFF00;
}

.status_header {
    background-color: #FFA500;
}

.status_duration {
    background-color: #00FFFF;
}

.breakpoint {
    background-color: #cccccc;
    border: 1px solid black;
}

Selenium: simulating click on GWT buttons

In web applications, buttons which are rendered by GWT (google-web-toolkit) cannot be clicked. Selenium RC doesn't recognize them as HTML button. so following will not work for those type of buttons/element

selenium.click(elementLocator)

After some googling, I found out that we can click on these elements by native key events with follwoing code.

 public static void clickOnGWTPopElement(String elementLocator) {
  try{
   //normal click doesn't work on GWT popup elements so we need to perform native mouse operations
   selenium.mouseOver(elementLocator);
   selenium.mouseDown(elementLocator);
   selenium.mouseUp(elementLocator);
  }catch (Exception e) {
   e.printStackTrace(); 
  }  
 }

Write data into Excel file using Apache POI

IN my previous post, I posted code for reading excel file using Apache POI library. In this post I'll cover, how can we write data into excel. Here is the code:

package com.qa.test;

import java.io.FileOutputStream;
import java.util.Iterator;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;

public class SpreadSheetWriter {
	
	 /** This method writes data to new excel file **/
    public static void writeDataToExcelFile(List> data, String fileName) 
    {
    	try{
	    	HSSFWorkbook myWorkBook = new HSSFWorkbook();
	        HSSFSheet mySheet = myWorkBook.createSheet();
	        HSSFRow myRow = null;
	        HSSFCell myCell = null;
	        
	        //Create header row
	        createHeaderRow(mySheet);
	        
	        int rowNum = 1;
	        Iterator> iter = data.iterator();
	        while(iter.hasNext())
	        {
	        	myRow = mySheet.createRow(rowNum++);
	        	int cellNum = 0;
	        	
				List key = iter.next();
				for(String values: key)
				{
					myCell = myRow.createCell(cellNum++);
					myCell.setCellValue(values);
				}
			}
	
	        FileOutputStream out = new FileOutputStream(fileName);
            myWorkBook.write(out);
            out.close();
        }catch(Exception e){ 
        	e.printStackTrace();
        }         
   }
    
 }

Read Excel file using apache POI library

If you want to read Excel file in Java, Apache POI is the library which supports to read/write microsoft documents. Here is the code to read an Excel file.

import java.io.FileInputStream;
import java.io.InputStream;
import java.util.Iterator;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Row;

public class ReadExcel {
 
 public static void main(String[] args){
  
  try{
   InputStream myxls = new FileInputStream("C:\\exceltest.xls");
   HSSFWorkbook wb     = new HSSFWorkbook(myxls);
   
   HSSFSheet sheet = wb.getSheetAt(0); 
   
   Iterator rows = sheet.rowIterator();
   
   System.out.println("Total Rows :: " + sheet.getLastRowNum());
   
   //Iterate over each row
   while (rows.hasNext()) 
   {
    HSSFRow row = (HSSFRow) rows.next();
    if(checkIfRowEmpty(row)) 
     continue;
    
    int minColIndex = row.getFirstCellNum();
    int maxColIndex = row.getLastCellNum();
    
    for(int colIndex = minColIndex; colIndex <= maxColIndex; colIndex++) 
    {
     HSSFCell cell = row.getCell(colIndex);
     
     // POI can't recognize empty cells of Excel, so we should create new cells with a blank value
     if(cell == null) 
     {
        cell = row.createCell(colIndex);
           cell.setCellValue(" ");
     }    
     String value = "";
     
     switch(cell.getCellType())
     {
      case HSSFCell.CELL_TYPE_NUMERIC:
       value = Double.toString(cell.getNumericCellValue());
       break;
      case HSSFCell.CELL_TYPE_BOOLEAN:
       value = Boolean.toString(cell.getBooleanCellValue());
       break;
      case HSSFCell.CELL_TYPE_BLANK:
       value = "";
       break;
      case HSSFCell.CELL_TYPE_ERROR:
       value = "";
       break;
      case HSSFCell.CELL_TYPE_FORMULA:
       value = "";
       break;
      default:
       value = cell.getStringCellValue();
       break;
     }
     System.out.print(value + "|");
    }
    System.out.println();
   }
  }
  catch(Exception e){
   e.printStackTrace();
  }
 }
 
 public static boolean checkIfRowEmpty(HSSFRow row) 
 {
  int minColumIndex = row.getFirstCellNum();
  int maxColumnIndex = row.getLastCellNum();
  
  boolean isRowEmpty = true;
  for(int columIndex = minColumIndex; columIndex <= maxColumnIndex; columIndex++) 
  {
   HSSFCell cell = row.getCell(columIndex);
   if(cell == null || cell.toString().trim().isEmpty() || cell.toString().length() == 0){
    
   }
   else{
    isRowEmpty = false;
    return isRowEmpty;
   }
  }
  return isRowEmpty;
 }
}

Running multiple version of firefox

If you want to run multiple versions of firefox on same machine, follow below steps:

1. Close your all running instances of firefox
2. Download older versions of firefox from http://www.oldversion.com/Mozilla-Firefox.html and do a custom install, install them on a specific version directory. For example I installed them as below:
C:\Program Files\Mozilla Firefox_6.0.2
C:\Program Files\Mozilla Firefox_7.0.1
3. Create profiles for every version by following steps:
    A. Goto Run command (or press WINDOWS+R)
    B. C:\Program Files\Mozilla Firefox_6.0.2 -P
    C. It will open a profile window, Create a profile name with 'Firefox6.0.2'
4. Repeat step 3 for all firefox versions, create unique profile for each version
5. To run a specific version of firefox use below command:
<path to firefox executable> -no-remote -P <profile name>


C:\Program Files\Mozilla Firefox_6.0.2\firefox.exe -no-remote -P Firefox6.0.2
C:\Program Files\Mozilla Firefox_7.0.1\firefox.exe -no-remote -P Firefox7.0.1