Sample Code
String, char, int
public class StrAsc
{
public static void main (String args [])
{
String s = "A String";
System.out.println("The character at index 2 is " + s.charAt(2));
System.out.println("The ASCII equivalent is " + (int)s.charAt(2));
}
}
Exercises
- Convert the following string to its ASCII values: “I never saw a purple cow”
- If a = 1, b=2, c=3… convert the following String to its equivalent character codes: “DailyJava”
- ROT13 (“rotate by 13 places”, sometimes hyphenated ROT-13) is a simple letter substitution cipher that replaces a letter with the letter 13 letters after it in the alphabet. ROT13 is an example of the Caesar cipher, developed in ancient Rome. Write a program that will accept a String as input then output that string under a ROT13 transformation, so input of HELLO will result in output of URYYB
- Write a ROT-N cipher, similar to a ROT13 cipher, where a string and a shift are input, and a string is outputted with the characters shifted by N, so if the input is “DAD” and 1, the output is “EBE”
- Write a program that uses ASCII values to convert lowercase characters to uppercase, so input of “this” will result in output of “THIS”. DO NOT use library methods such as toUpperCase()
- There are 62 Alphanumeric Characters: [A-Za-z0-9]. Any other character, such as %,(): is non-alphanumeric. There are also a number of control or non-printing characters. These include Line Feed, Carriage Return and Tab. Write a program that imports a text file and prints the number of alphanumeric characters it contains.
- Write a program that accepts a string cipher as an input and ouputs a string plaintext containing every second letter from input. Test your program using the input “Knives” and “Forks”. You should get the output “nvs” and “ok” respectively
Tony Ballantyne Tech 