daattali · redwing92 · May 12, 2020 · May 12, 2020 · May 12, 2020 · May 12, 2020
diff --git a/_config.yml b/_config.yml
@@ -1,28 +1,24 @@
 # --- Basic options --- #
 
 # Name of website
-title: My website
+title: Jake Heo
 
 # Short description of your site
-description: A virtual proof that I'm awesome
+description: Information of Jake Heo
 
 # Your name to show in the footer
-author: Some Person
+author: Jake Heo
 
 # --- List of links in the navigation bar --- #
 
 navbar-links:
   About Me: "aboutme"
-  Resources:
-    - Beautiful Jekyll: "https://beautifuljekyll.com"
-    - Learn markdown: "https://www.markdowntutorial.com/"
-  Author's home: "https://deanattali.com"
-
+
 # --- Logo --- #
 
 # Image to show in the navigation bar - works best with a square image
 # Remove this parameter if you don't want an image in the navbar
-avatar: "/assets/img/avatar-icon.png"
+# avatar: "/assets/img/profile.png"
 
 # By default, the image is cut into a circle. You can disable this behaviour here.
 round-avatar: true
@@ -31,20 +27,20 @@ round-avatar: true
 # then specify the following parameter
 #title-img: /path/to/image
 
+cover-img: "/assets/img/profile.png"
 
 # --- Footer options --- #
 
 # Select the social network links that you want to show in the footer.
 # Uncomment the links you want to show and add your information to each one.
 # If you don't want to show a link to an RSS feed, set rss to "false".
 social-network-links:
-  email: "[email protected]"
-  facebook: deanattali
-  github: daattali
-  twitter: daattali
-  rss: true
+  email: "[email protected]"
+#  facebook: deanattali
+  github: gyucheonheo
+#  rss: true
 #  reddit: yourname
-#  linkedin: daattali
+  linkedin: gyucheon-heo-07a007157
 #  xing: yourname
 #  stackoverflow: "3943160/daattali"
 #  snapchat: deanat78
@@ -62,13 +58,12 @@ social-network-links:
 
 # Select which social network share links to show in posts
 share-links-active:
-  twitter: true
-  facebook: true
+#  facebook: true
   linkedin: true
 
 # How to display the link to your website in the footer
 # Remove this if you don't want a link in the footer
-url-pretty: "MyWebsite.com"
+url-pretty: "gyucheonheo.github.io"
 
 # Create a "tags" index page and make tags on each post clickable
 link-tags: true
@@ -80,14 +75,14 @@ excerpt_length: 50
 
 # Personalize the colors in your website. Colour values can be any valid CSS colour
 
-navbar-col: "#F5F5F5"
-navbar-text-col: "#404040"
+navbar-col: "#FFFFFF"
+navbar-text-col: "#000000"
 navbar-border-col: "#EAEAEA"
 page-col: "#FFFFFF"
 link-col: "#008AFF"
 hover-col: "#0085A1"
-footer-col: "#F5F5F5"
-footer-text-col: "#777777"
+footer-col: "#FFFFFF"
+footer-text-col: "#FFFFFF"
 footer-link-col: "#404040"
 
 # Alternatively, the navbar, footer, and page background can be set to use background images

diff --git a/_posts/2020-02-26-flake-it-till-you-make-it.md b/_posts/2020-02-26-flake-it-till-you-make-it.md
diff --git a/_posts/2020-02-28-test-markdown.md b/_posts/2020-02-28-test-markdown.md
diff --git a/_posts/2020-05-18-Stay-Away-Commenting b/_posts/2020-05-18-Stay-Away-Commenting
@@ -0,0 +1,7 @@
+---
+layout: post
+title: Stay Away Commenting to Your Code
+subtitle: Why do you need it?
+tags: [clean code]
+comments: true
+---
diff --git a/_posts/2020-05-19-Polymorphism.md b/_posts/2020-05-19-Polymorphism.md
@@ -0,0 +1,16 @@
+---
+layout: post
+title: If..Else..Switch..Polyporphism?
+subtitle: What is good about it?
+tags: [clean code, OOP, Polymorphism]
+comments: true
+---
+
+I recently saw a nerd meme in Facebook. It gives me so many thought with respect to polymorphism.
+![polymorphism](/assets/img/polymorphism.png)
+
+Can you see polymorhpism on the second code? So what could be advantages by doing so?
+
+
+
+
diff --git a/_posts/2020-05-23-Mistake-On-Git.md b/_posts/2020-05-23-Mistake-On-Git.md
@@ -0,0 +1,68 @@
+---
+layout: post
+title: Did you mess up with git commit? No Worry!
+subtitle: Let's go back to where it works
+tags: [git]
+comments: true
+---
+
+Everytime I learn about `git`, I frequently was likely to focus on adding/updating files. Because of that, I went through silly and stupid procedure or left those stupid whenever I did make mistakes. 
+
+It is NOW time for us to learn smart ways to revert it!
+
+### Scenario 1; Wrong Commit Message? No Problem!
+It it really common that you forget adding more files or put a bad message to a commit that you just made. 
+What would you do in this case? Are you going to leave it as it is or do you want to fix that?
+I hope that you want to do the latter. Here are steps you need to follow to do so.
+
+``` bash
+(master)[you@machine]$>git commit --amend -m "<new message>"
+```
+
+{: .box-warning}
+**Warning:** This commint will create a new commit number.
+
+### Scenario 2; Made commit to a wrong branch? No Problem!
+Imagine that you made a below commit to `master` branch. However, you figured out that this commit was supposed to belong to `foo` branch.
+
+``` bash
+(master)[you@machine]$>git add test.c
+(master)[you@machine]$>git commit -m "Completed new foo feature"
+```
+Ouch! you noticed the branch name is `master` instead of `foo`. Don't worry. It will cover.
+
+``` bash
+(master)[you@machine]$>git branch
+```
+The above command will show you two branches; `master` and `foo`. Okay. `foo` is our final destination. In addition, we need a commit number that we want move to `foo`. 
+
+``` bash
+(master)[you@machine]$>git log
+```
+
+The above command will show you a bunch of commit log and copy/paste the commit number.
+
+``` bash
+(master)[you@machine]$>git checkout foo
+```
+
+It enables you to switch your current branch to `foo`.
+
+``` bash
+(foo)[you@machine]$>git cherry-pick <the commit number>
+```
+
+Okay. Here we go. `foo` branch, now, has that commit.
+
+But! we should fix our `master` branch as well.
+
+``` bash
+(foo)[you@machine]$>git checkout master
+```
+
+``` bash
+(master)[you@machine]$>git reset --<soft or mix or hard> <the commit number>
+```
+* `soft` : `soft` will reset the commit, but changes will remain in working stage.
+* `mix`  : `mix` is the default. `mix` will reset the commit, but changes will remain in working directory.
+* `hard` : `hard` will reset the commit, but changes will NOT remain anywhere.
diff --git a/_posts/2022-09-14-Sort-List-with-fixed-order.md b/_posts/2022-09-14-Sort-List-with-fixed-order.md
@@ -0,0 +1,65 @@
+---
+layout: post
+title: Sort List with fixed start items 
+subtitle:
+tags: [java, stream, sort]
+comments: true
+---
+
+Recently, I needed to write a piece of code snippet to convert a list of strings into a list of strings that should start with 2 items. 
+I started it with being dumb.
+
+Let's say that your list should start with "Chicago" followed by "Illinois" and you don't care a rest of them once you meet "Chicago" followed by "Illinois".
+Additionally, a given list may or may not have "Chicago" or "Illinois".
+
+The first code that I pumped out smells a lot. 
+1. Too many if-else : I'm lucky to have only 2 items requirement. What if it should starts with 10 items? Its complexity will grow exponentially. Error-prone.
+2. I repeat myself
+3. In general, it is vomit-causing code. I hate it.
+
+``` java
+List<String> newList = new ArrayList<>();
+List<String> lst = List.of("San Fransisco", "California", "St Louis", "Missouri", "Washington", "Seattle", "Chicago", "Wisconsin", "Illinois");
+
+if (lst.contains("Chicago") && lst.contains("Illinois")) {
+    for (String s : lst) {
+        if (s.equals("Chicago")) newList.add(0, s);
+        else if (s.equals("Illinois")) newList.add(1, s);
+        else newList.add(s);
+    }
+} else if (lst.contains("Chicago") && !lst.contains("Illinois")) {
+    for (String s : lst) {
+        if (s.equals("Chicago")) newList.add(0, s);
+        else newList.add(s);
+    }
+} else if (!lst.contains("Chicago") && lst.contains("Illinois")) {
+    for (String s : lst) {
+        if (s.equals("Illinois")) newList.add(0, s);
+        else newList.add(s);
+    }
+} else {
+    for (String s : lst) {
+        newList.add(s);
+    }
+}
+
+newList.forEach(System.out::println);
+```
+
+As a result of spending a few hours playing the code, I ended up sorting it based on fixed items.
+It's pretty intuitive and there is nothing that I have to explain as extra. 
+Neat and simple.
+
+``` java
+Map<String, Integer> fixedItems = Map.of("Chicago", 0, "Illinois", 1);
+List<String> lst = List.of("San Fransisco", "California", "St Louis", "Missouri", "Washington", "Seattle", "Chicago", "Wisconsin", "Illinois");
+
+List<String> newList = lst.stream()
+                          .distinct()
+                          .sorted(Comparator.comparing( s -> {
+                            int i = fixedItems.getOrDefault(s, -1);
+                            return i >= 0 ? i : fixedItems.size();
+                            }))
+                          .toList();
+```
+Although the number of fixed items increase, this code will be able to handle it in scale without any changes except for `fixedItems`. 
diff --git a/_posts/2023-06-01-asymmetric-encryption.md b/_posts/2023-06-01-asymmetric-encryption.md
@@ -0,0 +1,47 @@
+---
+layout: post
+title: How securely shares your secret with others?
+subtitle:
+tags: [encryption, decryption, openssl]
+comments: false
+---
+
+Do you plan to share your secret, such as apikey, application secret, password, to your colleagues? But you don't want them to be stored in a persistant storage such as a messenger's database.
+Then, let's follow it
+
+Let's make up a situation.
+Alice asks me to renew an apikey because Alices needs one more for a new application domain.
+She told me "Send it to me through Slack!".
+However, Slack stores our conversation and it'd be security breach candidate while scanning!
+You and Alice and follows this.
+1. Alice generates her private key
+``` bash
+$>openssl genpkey -algorithm RSA -out private_key.pem
+```
+
+2. Alice extracts her public key out of her private key
+``` bash
+$>openssl rsa -pubout -in private_key.pem -out public_key.pem
+```
+
+3. Alice shares her *public* key
+
+4. You encrypts a file that includes a secret
+``` bash
+$>openssl rsautl -encrypt -pubin -inkey public_key.pem -in plaintext.txt -out encrypted.bin
+```
+
+5. You share an output file `encrypted.bin` to Alice
+
+6. Alice descrypts the file `encrypted.bin` using her *private* key
+``` bash
+$>openssl rsautl -decrypt -inkey private_key.pem -in encrypted.bin -out decrypted.txt
+```
+
+Asymmetric encryption is a powerful tool that can be used to protect sensitive information. It is often used in conjunction with other security measures, such as passwords and authentication tokens, to create a more secure system.
+
+Here are some additional benefits of using asymmetric encryption:
+
+Confidentiality: Asymmetric encryption can be used to protect sensitive information from unauthorized access.
+Integrity: Asymmetric encryption can be used to ensure that the contents of a message have not been tampered with.
+Non-repudiation: Asymmetric encryption can be used to prove that a message was sent by a specific person.