In this blog post “Balanced Binary Search Tree“, I introduce two balanced binary search trees, which are AVLTree and RedBlackTree. AVLTree is efficient for search. Its time complexity is O(logN) for search, insertion and deletion. It usually takes one top-down… Read More
bash command history
Yesterday morning after arriving at the office, I booted up my laptop as usual and tried to connect to my Linux development server using putty. However, the ssh connection couldn’t be established successfully. After struggling for a while, I found… Read More
an introduction to policy-based routing in Linux
A few days ago I was assigned a task to create pods with multiple network interfaces in the Kubernetes. It is not a difficult task, because it only requires a few annotations for the pods, provided that the CNI network… Read More
request access token from keycloak using restapi
A few days ago, I was assigned a task to write a script to request access token from keycloak using restapi. After googling in the internet, I got the answer. Mark it here for later reference: curl -L -X POST… Read More
disable disk check during bootup for Ubuntu
As I mentioned in this post, I am using Ubuntu Linux in my xiaomi laptop. However, I am disturbed now and then these days by the disk check during the Ubuntu bootup. If I miss the very first few seconds,… Read More
list files in a package in ubuntu
The below command can be used to list files in a package in Ubuntu apt-file list <package-name> or dpkg -L <package-name> for example, apt-file list openjdk-8-doc or dpkg -L openjdk-8-doc
国内无法访问google字体api
最新几天发现自己的博客有点问题。就是网页打开特别慢，大概需要花费几十秒的时间。并且页面打开后，网页字体也不对。之前在公司访问自己的页面，没有发现什么问题，不过最近几天在家里访问时，就会出现这个问题。今天周末花了点时间看了一下，发现原来是google字体api服务器又被国家防火墙给屏蔽。
the phases in CMS garbage collector
In the post ‘Brief Introduction to Java Generation Memory‘ and ‘an introduction to young generation collection‘, I described the java generation memory and the young generation collection. In this post I will describe one Java garbage collector, name CMS. CMS,… Read More
normal form for database table
The below normal forms should be enforced when the table of a database is designed. First Normal Form: A table is not in first normal form if it stores multiple values for a piece of information. Action: If a table… Read More
an introduction to young generation collection
In the post ‘brief introduction to java generation memory‘, I explained the functionality of the young generation and old generation. These two generation spaces consist of the main heap of the java application. In fact, there is a third generation… Read More