Endianness mnemotechnic

A long time ago I had a difficult time trying to remember the differences between Big Endian and Little Endian. I came out with this little trick to make it easier to remember: associate Low with 0.

In Big Endian, you store the most significant byte in the smallest address. In Little Endian, you store the least significant byte in the smallest address.

http://en.wikipedia.org/wiki/Endianness

Guava Files class

Sometimes you are still in the Java 1.6 land and you just to want to read the entire file into a list. Guava can help you:

File file = new File("trades_3.txt");
List<String> lines = Files.readLines(file, Charset.defaultCharset());

The Files class doc.

Foundation and Empire

1. Part I: The General
1. Search for Magicians
2. The Magicians
3. The Dead Hand
4. The Emperor
5. The War Begins
6. The Favorite
7. Bribery
8. To Trantor
9. On Trantor
10. The War Ends
2. Part II The Mule
11. Bride and Groom
12. Captain and Mayor
13. Lieutenant and Clown
14. The Mutant
15. The Psychologist
16. Conference
17. The Visi-Sonor
18. Fall of the Foundation
19. Start of the Search
20. Conspirator
21. Interlude in Space
22. Death on Neotrantor
23. The Ruins of Trantor
24. Convert
25. Death of a Psychologist
26. End of the Search

IPTABLES

# List the rules with line numbers,
# the -n disables the DNS reverse lookup
iptables -n --list --line-numbers

# Block a specific IP
iptables -A INPUT -s 192.168.0.1 -j DROP

# Allow SSH for a specific IP
iptables -A INPUT -s 192.168.0.2 -p tcp -m tcp --dport 22 -j ACCEPT

# Delete a rule based on its number
iptables -D INPUT 8

# Insert rule before other certain one
# For example before line # 3
iptables -I INPUT 3 -s 192.168.0.2 -p tcp -m tcp --dport 22 -j ACCEPT