Java is the most regularly used programming language for the creation of web applications. This high-level programming language develops by the Sun Micro-system. This language was designed for use in the world of internet and known for fastest, secure, and most reliable language of the computing platform. One interesting fact is that Java programmers are…
How to do screen recording on Wayland in Linux? Many screen recorders do not work on the new Wayland. Using Green Recorder You may try Green Recorder which supports Wayland. Note: Green Recorder is no longer under development by the original author (Please check the project README for more details). It still works well for…
It is common that the root disk space is not enough when running a Virtual Machine in the cloud such as Amazon Web Service (AWS). The cloud storage usually provides tools or facilities to enlarge a virtual disk size. However, to make the Linux recognize and and use the enlarged disks without rebooting the OS,…
Reading: Years in Big Data. Months with Apache Flink. 5 Early Observations With Stream Processing: https://data-artisans.com/blog/early-observations-apache-flink. The article suggest adopting the right solution, Flink, for big data processing. Flink is interesting and built for stream processing. The broader view and take away may be to solve problems using the right solution. We saw many painful…
Google Drive is a nice cloud storage service. It provides a suite of nice online document spreadsheet and slide editors Google Docs, Google Sheets and Google Slides. The collaborative editing and full history tracking features of Google Docs are excellent. Google Drive gives 16GB free storage which is pretty much larger compared to other free…
How to rename a branch name in the remote git server? For example, I made a mistake to push a branch named ood-name to the git server while I intended to name it old-name. How to rename the branch name ood-name on the remote git server? You may change the remote git server’s branch name…
How to get the date and time from another timezone in Python? You may use the pytz library. Example usage as follows. $ python3 Python 3.8.2 (default, Jul 16 2020, 14:00:26) >>> from datetime import datetime >>> import pytz >>> >>> print(datetime.now(pytz.timezone(‘Europe/Amsterdam’)).strftime(‘%Y-%m-%d %H:%M:%S %Z%z’)) 2020-08-09 15:50:00 CEST+0200 >>>
The way for Ubuntu 17 to installing the gnome-shell-extensions package does not work any more for Ubuntu 18.04. How to enable user themes in Ubuntu 18.04? The updated gnome-shell-extensions package actually adds the User Theme extension back. You can use that. First, install the package sudo apt install gnome-shell-extensions Second, log out and login again…
date command on Linux gets the date and time in the system timezone. But how to get date and time using date command from another timezone in Linux? You can make date print the time of another timezone by setting the TZ environment variable. For example, export TZ=Hongkong; date Sat Dec 1 09:39:13 HKT 2018…
If I quite a docker instanced (invoking /bin/bash) by Ctrl+d, the docker container is closed. How to detach a docker container to be a running daemon without closing it? Docker has a detach sequence, which, by default, is Ctrl-p + Ctrl-q. If the docker detach sequence is overridden by the –detach-keys=”<sequence>” flag, you need to…
In Ubuntu 18.04, Thunderbird shows huge emoji icons in the email list. The emoji covers other text and is several lines higher and wider than other charactors. How to solve it? This is likely caused by the fonts. Find out the *emoji* fonts installed in your system by sudo apt list *emoji* and remove those…
How to change the logo shown during booting in Ubuntu? I originally installed Ubuntu MATE 18.04. But I am using GNOME 3 now by replacing the DE. But the log shown during booting is still Ubuntu MATE’s. How to change it to another one? It is plymouth the application that manages the “splash” screen during…
In GNOME 3 “Settings” -> “Devices” -> “Mouse & Touchpad”, after setting “Natural scrolling” to On, the scrolling is still as the same before (non-natural). How to fix this? This is likely related to the X11 driver. Remove the xorg-x11-drv-synaptics driver if it is installed. And install the xorg-x11-drv-libinput driver if it is not installed….
How to install the GNOME 3 (gnome-shell) desktop environment in Ubuntu MATE 18.04? To install gnome3 to Ubuntu, install these packages sudo apt install gnome-session gdm3 ubuntu-desktop During installation, the installation tools will let you choose the default display manager. You may choose gdm3. Then reboot you Ubuntu Linux and gdm3 will be shown. Click…
Zlib is a popular open-source compression library used by many software applications to compress and decompress data. While it can be installed in Ubuntu using the apt package manager, you may need to install it from the source code if the version available in the Ubuntu repositories is outdated or if you need to customize…
How to add Chinese input method, such as Pinyin, to Unbuntu 18.04? To input Chinese, first install an input method framework. Here, we use fcitx. Then you need to input the Pinyin input method. You may use fcitx-sunpinyin. Put them all together $ sudo apt-get install fcitx fcitx-sunpinyin After that, set the default input method…
Thunderbird is powerful and feature rich. But different users have different needs and it is not feasible to include all features into the base software, where a plugin system shines. Thunderbird, similar to Firefox from Mozilla, supports addons/plugins and has a large ecosystems. Here, we will introduce several addons to Thunderbird that make Thunderbird easier…
How to test a path (a file or directory exists) in golang? In Bash, the [ -e ] tests can test whether a file or a directory exist. What are the corresponding Go ways for the test? You can use the `os.Stat()` and `os.IsNotExist()` standard libraries functions together to test whether a file or a…
How to convert a string to lower case in Python? For example: “Abc” -> “abc” “BBB” -> “bbb” “abc” -> “abc” You can use the string.lower() method of Python: string.lower(s) Return a copy of s, but with upper case letters converted to lower case. Example: $ python Python 2.7.5 (default, Apr 11 2018, 07:36:10) [GCC…
In WordPress, we can filter the post content by adding a filter to the_content: add_filter('the_content', 'inline_markdown_pre_process_shortcode2', 7); But how to filter the content for bbpress contents? bbpress topic and reply (they are separated) content have their own filters: bbp_get_topic_content and bbp_get_reply_content. For example, add_filter(‘bbp_get_topic_content’, ‘my_plugin_custom_bbp_function’); add_filter(‘bbp_get_reply_content’, ‘my_plugin_custom_bbp_function’); function my_plugin_custom_bbp_function($content) { return ‘my_plugin_custom_bbp_function processed: ‘.$content; }