Java Training Course/Example Programs

All example Java programs can be obtained from a Git repository:

git clone https://github.com/gfis/jtc

Start with a greeting

• HelloWorld - output only

Arguments, assignment, elementary String and arithmetic operations

• StringAdd - concatenate argument strings 4 times and print them out
• IntAdd - add 4 integers 4 times and print them
• IntMultiply - multiply 4 integers 4 times and print the product
• LongMultiply - multiply 4 long numbers

Loops (while, for) and conditions (if), arrays ([])

• PowersOf2 - print the powers of 2
  • PowersOf2Check - check for increasing sequence
  • PowersOf2Backwards - print sequence backwards
  • PowersOf2Array - print sequence from an array

Sequences of conditions with switch, if - then - else if ...

• Selamat - print a greeting depending on the hour
• SelamatSwitch - same with switch ... case ... default
• Number10 - print the numbers 1..10
• Number10Method - print the numbers using a class method
• Month - print the indonese name of a month
• Weekday - print the indonese name of a weekday

Sequences of words

• Word1 - print all words with 1 letter
• Word2 - print all words with 2 letters by 2 nested loops
• Word3 - print all words with 3 letters by 3 nested loops
• Word3Cond1 - print words with 3 letters and vowel/consonant conditions, first version
• Word3Cond2 - same, using a method, 2nd version
• Word3Cond3 - same, output on a single line, 3rd version

Filtering files

A filter program reads a file, modifies all lines somehow, and writes them to another file.

• Filter1 - read a file and replace the vowels in each line
• FilterNumber - read a file and replace all digits by their indonese number words
• FilterMulti3 - read the modified output of Word3Cond3 and colorize the known words

Date and Calendars

• Age - enter a birthday and compute the elapsed years, months ... seconds up to now

Fractional arithmetic

• GreatestCommonDivisor - the first real algorithm
• Ratio - introduction to object oriented programming (static version)
• Rational - object with methods for mathematical operators for exact fractions
• RationalTestSwing, AboutRationalTest - GUI for the addition, subtraction, multiplication of two Rationals

Games

• PlayNim - play the Nim game with some number of sticks to be taken

' PlayNimState - improve clarity of program logic by using a Discrete Finite State Automaton (DFSA)

• PlayNimSwing, AboutPlayNim GUI for the Nim game