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Could not get lock /var/lib/dpkg/lock

Today, I tried to install Git on my Ubuntu machine and during that I received following exception related to locking. In my this post, I have shared all commands and error messages with you.


Command
sudo apt-get install git

Error Message
E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable)
E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?



After searching above message, I found a command
sudo lsof /var/lib/dpkg/lock
after pressing ENTER, it might asked you for password. Type the password and in result you might get following output
lsof: WARNING: can't stat() fuse.gvfsd-fuse file system /run/user/1000/gvfs       Output information may be incomplete. COMMAND    PID USER   FD   TYPE DEVICE SIZE/OFF   NODE NAME unattende        1468 root    5uW  REG    8,1        0 154817 /var/lib/dpkg/lock
Type following command to kill the session with provided PID by your system. In my case PID # was 1468. I use following comman…

NodeJS Series: Calling Sleep Method.

Dear Friends,

This is my first article about NodeJS, I am currently exploring it and problems which I found during my learning sessions, I will share it to you with my blog posts.

Today while writing some code, I come across the need of sleep functionality between two transactions. While doing google, I found "sleep" library which provide required functionality.

Calling of sleep method is simple e.g.,

sleep.sleep(1) // time will be defined in seconds 

But before that you need sleep library / package. To download it, use following npm command

npm install sleep

After successful installation, write following code to test this functionality.

var sleep = require('sleep');

function callLoops()
{
for(var a=1;a<10;a++)
{
console.log('%d',a);
sleep.sleep(1);//times in seconds.
}
}

callLoops();

and save this code in myExample.js file.

Execute the file with following command

node myExample.js

Congratulations...... You have achieved the goal.

That's all for now folks..... If …

HOW TO USE SPRINGFORM:ERROR TAG

To use Spring Form Error Tag, you have to follow following steps.

Your JSP Page should look like this:

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib prefix="sf" uri="http://www.springframework.org/tags/form" %>

<!DOCTYPE html>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
        <title>About Us Page</title>
    </head>
    <body>      
        <sf:form method="POST" action ="/SpringBasics/redirect.aspx" modelAttribute="basicClass">
        FirstName: <sf:input path="firstName" />
            <sf:errors path="firstName" />
        <br/>
            <input type="submit" value="Redirect Page" />    
        </sf:form>
    </body>
</html>


java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'xxx' available as request attribute

While trying to use Spring MVC form Tags, I come across following exception


java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'userInput' available as request attributeBelow is my JSP Code with Spring Tags<%@page contentType="text/html" pageEncoding="UTF-8" session="false" %> <%@taglib uri="http://www.springframework.org/tags" prefix="st"%> <%@taglib uri="http://www.springframework.org/tags/form" prefix="sf"%> <!DOCTYPE html> <html> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>About Us Page</title> <st:url var="bootstrapp_theme" value="/resources/css/bootstrap-theme.css" /> <st:url var="bootstrapp_css" value="/resources/css/bootstrap.css" /> <st:url var="jque…

No Launcher Load in Ubuntu

Sometimes UBUNTU does not show launcher due to some problem and in that case we have to re-install the O/S again. I come across this problem several times but today I did some research and found this easiest solution which work for me and I hope that It will work for you as well.

Follow below steps to get your UBUNTU launcher back:

1) Press CTRL+ALT+DTL in vm ware (3 Buttons combine) to open your processes window inside Virtual Machine.

2) Go to 3rd Tab (Disk) and double click on /dev/sda1. This will open your Files Explorer.

3) Now press CTRL+F for searching and find TERMINAL.

4) Open TERMINAL.

5) Write " sudo apt-get update "

6) Write " sudo apt-get install unity " to install Unity which will display you LAUNCHER.

7) Write " sudo reboot " to reboot your Virtual Machine.


After your computer / Virtual Machine is reboot, you can see your LAUNCHER back.

Above steps resolve my problem and if does the same in your case then please comment so the reliability …