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Small Changes to Java 7 via Project Coin and Why They are Useful

Did you know how new features were added into Java 7? The following are functionalities that can be considered.
Source: [1] Project Coin is all about the changes in the range from syntactic sugar to new language feature. This is what we're talking about today.

Since Java 7 is the first version developed in an open source manner, there is an amount of actions that must be performed for any changes as follows:
Update the Java Language Specification (JSL)Implement a prototype in the source compilerAdd library support essential for the changeWrite tests and examplesUpdate documentEtc, ... Project Coin has submitted a lot of proposals (almost 70) but only some of them are chosen to Java 7. Why? Briefly, Java is a rich static type system and it has a lot of possible interaction points between different bits of it. Making changes to this type system is prone to creating unexpected surprises.

Wow! It is tough, right? Let's take a look what features Project Coin brought to Java 7.
Strings…
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Climbing Fansipan – Highest Peak of Indochina

Fansipan is a mountain in Vietnam, the highest in Indochina, at 3,143 metres. It is located in the Lào Cai Province of the Northwest region of Vietnam, 9 km southwest of Sa Pa Township in the Hoang Lien Son mountain range. Wikipedia
Currently you can get the peak by cable car; however, I loved to explore it by climbing.

Here are what I have learned from this exciting journey. 💪
Do not procrastinate I have had no experience of climbing a high mountain before. Then, I've sought advice from my friends, but they suggested that I should not make it at that time due to bad weather and lack of experience. I know it never come true unless I just make my decision. Can't wait! Prepare for your journey You firstly need getting to know about the journey, schedule, transportation, etc. Recommended sources: YouTube videos, blog posts and tour companies websites.
Tips - Quality hiking shoes helps a lot - Bring your stuffs as light as possible. Important stuffs: a light raincoat and water (t…

Java Core - Top 10 Questions Every Developer Should Know

#RandomlyPickedByMe

What is the difference between Javascript and Java?Difference between StringBuilder and StringBuffer?Why do I get "SomeType@a3fde" when I print my code?Why is String immutable?Why "equals" method when we have "==" operator?Is List<Dog> a subclass of List<Animal>?Why shouldn't we use raw type?Is Java “pass-by-reference” or “pass-by-value”?What's the advantage of a Java enum versus a class with public static final fields?Why "double x = 0.1 + 0.2" and result of print(x) is 0.30000000000000004?
1. What is the difference between Javascript and Java? Holy crap! (Vietnamese: Thế quái nào lại có câu hỏi ngớ ngẩn vậy chứ?)

"Java and Javascript are similar like Car and Carpet are similar." - Greg Hewgill (on StackOverflow)
2. Difference between StringBuilder and StringBuffer String is immutable. StringBuilder and StringBuffer are mutable. StringBuffer is thread-safe. StringBuilder is modern than StringBuff…

Using Drools to Dynamically Manipulate Metadata of JSF Components

The post is just an approach to change metadata (e.g maxlength, required, etc) of JSF components (e.g. inputText, selectOneMenue, etc) by Drools.
Project structure Tools being usedJava version 1.8.0_131Apache Maven 3.5.0Apache Tomcat 8.0.16 Don't forget to configure your confidential information on  these following files: pom.xml, settings.xml (Maven) and tomcat-users.xml (Tomcat).
For example:
Source codehttps://github.com/vnnvanhuong/java_lab/tree/master/jsfdrools

Coding Exercise, Episode 1

I have received the following exercise from an interviewer, he didn't give the name of the problem. Honestly, I have no idea how to solve this problem even I have tried to read it three times before. Since I used to be a person who always tells myself "I am not the one good at algorithms", but giving up something too soon which I feel that I didn't spend enough effort to overcome is not my way. Then, I have sticked on it for 24 hours.

According to the given image on the problem, I tried to get more clues by searching. Thanks to Google, I found a similar problem on Hackerrank (attached link below). My target here was trying my best to just understand the problem and was trying to solve it accordingly by the Editorial on Hackerrank. Due to this circumstance, it turns me to love solving algorithms from now on (laugh). Check it out!
Problem You are given a very organized square of size N (1-based index) and a list of S commands
The ith command will follow the format (a[…

How Would You Answer These Typical Interview Questions?

I have joined several job interviews with candidates at my current company. As a technical supporter, my attention was mainly focused on specific technical points rather than behavioral ones. However, I saw that these following typicalquestions were rarely missed for any interviews. In fact, there is a meaning behind of the questions. The concern is candidates should focus on answering the right things that interviewers really want to know. Take a look!
Introduce about yourselfIt is "What and why are you fit for this job?". 
So, it is good to go "Talking too much about your hobbies."?
I would say "We don't care about your hobbies much". ;)
Why do you want to find a new job?It is "Why this job are interesting you?". 
So, it is good to go "Talking about something negative like 'I hate my boss/leader'"?
I would say "Who wants to work with a negative person?"
What did you do in your current job?It is "Tell us wha…

Building an App for Removing Multiple Slack's Files

You're a developer. What do you do in your spare time? One of my most excited task for sharpening my skills is starting build a pet project. MotivationSlack is cool! It's free. It supports for team collaboration very well.

However, my team only has storage limits due to a free account. We got a warning message as below:
Your file was uploaded — it’s safe and sound in Slack. Unfortunately your team doesn’t have any storage space left. To get more space, you can upgrade to a paid account or delete some of your older files. Since my team plan of upgrading to a paid account is still up in the air, I intended to go with "deleting some of our older files" first. (But we will, Slack. You are great!) Play Around I got started by googling keyword "remove slack files". Here it is:
https://get.slack.help/hc/en-us/articles/218159688-Delete-shared-files

Uh huh! But I only could delete one file at a time.
We're afraid it's not possible to bulk delete files. We kn…