1. CSE 1020:Software Development
Mark Shtern

2. Summary Error handling String Handling
The masquerade and the + operation
Applications
Character Frequency
Character Substitution
Fixed-Size codes
Variable-Size code
StringBuffer

3. Exercise 6.15
Write a program that reads a string and outputs its length exclusive of any trailing asterisks
For example, if the user entered “java**” the output should be 4
If the user entered “**” the output should be 0

4. Exercise 6.18
Write a program that reads a string and corrects one aspect of its spelling as follows:
The letter pair “ei” is replaced by “ie” unless it is preceded by c
For example, “BELEIVE, seive, conceive” becomes “BELIEVE, sieve, conceive”

5. Regular Expression

6. Pattern Matching Pattern matching problems:
Determine whether a given string is made up of two words
Determine whether a given string contains an integer surrounded by letters and separated from them by whitespace

7. Regular expression
It is a string that describes a pattern in a formal fashion
Pattern example:
"((0[0-9])||(1[0-2])):[0-5][0-9] [ap]m “  time

8. Character Specification
Range
[a-m]
Union
[a-m[A-M]]
Set
[abc]
Negation
[^abc]
Intersection
[a-m&&[^ck]]

9. Predefined specification
Any character .
A digit \d
A whitespace character \s
A word character \w
A punctuation character \p

10. Quantifiers x, once or not at all x, zero or more times
x, one or more times x+
x, at least n but not than m times
x{n,m}

11. String class
Methods
matches
replaceAll
split

12. Command-Line Arguments
Application launches as following
java <class name> <arg1> <arg2> <arg3>
Access to command line arguments
arg[0]  arg1
arg[1]  arg2
arg[2]  arg3

13. Exercise 6.22
Write a program that reads a DNA sequence from the user and determines whether it is valid
To be valid it must:
Contain only the letters A C G T
Start with ATG
Have a character count that is a multiple of 3