IDEA linux – import module hanging

I tried IDEA on linux. OF course, It started with gooling 😀

I tried to import the modules, but hanged… (on a freshly created project, with import maven modules)


The resolution was:

File -> invalidate caches and restart


Disabling UPS beep under Linux

But it will take about 3-5 minutes to make all the setup under Linux properly. We need to run a upscmd at last, but there are a few steps before that.

  • First of all, install nut package:

  • Append following lines to /etc/nut/ups.conf according to your ups device (descparameter not important, you don’t need to give correct brand name either but the given section name will be used later to identify configured ups device, we’re using eaton as config section name here):

  • Now start the upsdriver with upsdrvctl:

  • Run upsc command the get beeper status:

  • We’re so close, now append following lines to /etc/nut/upsd.users, change the username admin or password as you want:

  • Reload upsd with the new users config:

  • You can query the list of the commands which will be supported by your ups device with the upscmd:

  • As you can see, there is a command named beeper.disable and we’ll be execute this command (give the username and password which we configured just before):

  • Now check the beeper status again:

That’s it. It takes some time but your ears will be happy.



Apache CXF Without spring

I found a very good blog post about that topic, here:

I copied there, to be here also for the future:

Apache CXF First JAX-WS (SOAP Web Service) Example (CXFNonSpringServlet)

The most of the people think that the Apache CXF supports only to develop Spring based Web Services. this is NOT true. is supports to build both Spring based and Non spring based web services.
1. CXFServlet –  this will support for the Spring based web services.
2. CXFNonSpringServlet –  this will support for the non spring web services.the purpose of this article is to demonstrate how to develop non spring based web service with Apache CXF. i have already developed and  tetsed the service with SoapUI. i am just sharing the source code for your reference.the project structure looks as below.,


the following is the Service Endpoint Interface(SEI).

the following is the Service Implementation Bean (SIB)

the custom implementation for the CXFNonSpringServlet.



Source code can be downloaded at :-

Chathuranga Tennakoon


OpenVPN Android client, error msg: “option or or was not properly closed out”

The fckn openvpn always s**ked me on android…

I found, why:

I have learned:
1. Filename extension *must* be lowercase
2. Remove all space(s) between last character(s) and CrLf. E.g.:
<CA>{SPACE}CrLf to


Sierra Wireless EM7455 Qualcomm Snapdragon X7 LTE-A – PIN2 – NPCap

I bought a DELL notebook with LTE modem Sierra Wireless EM7455 Qualcomm Snapdragon X7 LTE-A. After that, I installed Whireshark with NPCap.


After that, my WWAn connetion didn’t work more.


I used the windows troubleshooter and it sometimes put a result to me, I have to add my PIN2 number.


After that, I googled a lot, and I find this article.


Uninstalled NPCap, and the LTE modem works very well.


Ubuntu/Debian (linux) WSL and Docker

If you would like to use docker on windows Ubuntu/Debain WSL you have to modify the .bashrc file in your home directory.

and add this line to the end:

reload the modifications:

That’s all folks 😀

Ubuntu WSL add git brach name to promt

you have to mofify ~/.basrc from that:



Modification details:

  • add $(parse_git_branch)\[\033[00m\] 
  • and COMMENT the unset color_prompt force_color_prompt line


Transmission network problem

Recently started in debug mode on Transmission and I see:

[17:42:40.319] UDP Failed to set receive buffer: requested 4194304, got 262142 (tr-udp.c:75)
[17:42:40.319] UDP Please add the line "net.core.rmem_max = 4194304" to /etc/sysctl.conf (tr-udp.c:80)
[17:42:40.319] UDP Failed to set send buffer: requested 1048576, got 262142 (tr-udp.c:86)
[17:42:40.319] UDP Please add the line "net.core.wmem_max = 1048576" to /etc/sysctl.conf (tr-udp.c:91)

By tuning the two variables, higher throughput can be achieved more easily using uTP.

Here’s the relevant part from the changeset :

Since we are using a single UDP socket to implement multiple UTP sockets,
and since we are not always timely in servicing an incoming UDP packet,
it is important to use a large receive buffer. The send buffer is probably
less critical, we increase it nonetheless.

Four megabytes might seem huge for embedded clients, but running behind a dedicated connection, it might even become too small. I recommend using 16 megabytes for receive buffering and 4 for the send buffer. That is, because uTP implements a retransmission algorithm and by scaling up the buffers we can achieve fewer retransmits because of dropped datagrams. Let’s set it up that way.

Check actual settings:

do the modifications:


Oracle 11g XE install on Ubuntu 14/16

After Ubuntu downloaded and installed.

First install Java:


Reload sources:


result should be:

Second: Download and prepare Oracle DB

Copy the downloaded file and paste it in home directory.

Unzip using the command:

Install required packages using the command:

Enter into the Disk1 folder using command:

Convert RPM package format to DEB package format (that is used by Ubuntu) using the command:

Create the required chkconfig script using the command:

The pico text editor is started and the commands are shown at the bottom of the screen. Now copy and paste the following into the file and save:

Change the permission of the chkconfig file using the command:

Set kernel parameters. Oracle 11gR2 XE requires additional kernel parameters which you need to set using the command:

Copy the following into the file and save:

Verify the change using the command:

You should see what you entered earlier. Now load the kernel parameters:

Verify the new parameters are loaded using:

You should see the file-max value that you entered earlier.

Set up /dev/shm mount point for Oracle. Create the following file using the command:

Copy the following into the file and save.

Change the permissions of the file using the command:

Now execute the following commands:

Install Oracle

Install the oracle DBMS using the command:

Configure Oracle using the command:

Setup environment variables by editting your .bashrc file:

Add the following lines to the end of the file:

Load the changes by executing your profile:

Start the Oracle 11gR2 XE:

Add user YOURUSERNAME to group dba using the command:


src: and

gentoo beragadt init script takarítása