Collection of programming selection tasks to make and remember (Java basics)

For those who have learned the grammar to some extent and want to make something, I have collected and organized some affordable tasks. All are independent so you can work from anywhere. Maybe it can be used other than Java? Please use it for new employee education and killing time.

table of contents

Level 1 FizzBuzz * Time guide 1 hour Warming up

[Level 2 Multiplication Table]( 81% 91% E7% AE% 97% E4% B9% 9D% E4% B9% 9D) * Time guide 2 hours How to use loops, function

[Calculation of Level 3 Zodiac]( 94% AF% E3% 81% AE% E8% A8% 88% E7% AE% 97) * Time guide 4 hours A little complicated logic (argument, 2D array)

[Level 4 membership registration function]( 93% A1% E7% 99% BB% E9% 8C% B2% E6% A9% 9F% E8% 83% BD) * Time guide 6 hours Classes and instances, JavaBeans

[Level 5 Music Player]( % A5% E3% 83% BC% E3% 82% B8% E3% 83% 83% E3% 82% AF% E3% 83% 97% E3% 83% AC% E3% 82% A4% E3% 83% A4 % E3% 83% BC) * Estimated time 8 hours Inheritance and interface

Level 1 FizzBuzz

First of all, warm up with this. Estimated travel time: 1 hour


Outputs "Fizz" when it is a multiple of 3, "Buzz" when it is a multiple of 5, and "FizzBuzz" when it is divisible by both 3 and 5.

Program list

Level 2 multiplication table

The goal is to get used to using loops. Estimated travel time: 3 hours


Output to the console like this

1 2 3 4 5 6 7 8 9 2 4 6 8 10 12 14 16 18 3 6 9 12 15 18 21 24 27 4 8 12 16 20 24 28 32 36 5 10 15 20 25 30 35 40 45 6 12 18 24 30 36 42 48 54 7 14 21 28 35 42 49 56 63 8 16 24 32 40 48 56 64 72 9 18 27 36 45 54 63 72 81

Insert a tab character between characters

Program list


--Multiplication uses a double loop --Use escape sequences for character spacing and line breaks

Level 3 Zodiac Calculation

It is a program that calculates the zodiac from 4 digits in the Christian era. The goal is to get used to a little complicated logic.

■ Message example The 2017 zodiac sign is the year of the fire rooster.

Estimated travel time: 6 hours


See below

Program list


Heavenly Stems and Heavenly Stems are calculated based on the remainder of dividing year by a specific number. Heavenly Stems and Zodiac are defined by enum, and the one calculated above is returned. For example, if the result calculated from year is 0, the result will be "Geng". It is supposed to be implemented using an enum, but if you get stuck without knowing it, you can implement it using a conditional branch in an if statement or a switch statement.

Level 4 membership registration function

The goal is to get used to using classes, instances, and JavaBeans. Estimated travel time: 6 hours


Please register the member information for 3 people and output the following words on the console. Taro Yamada's member ID is 0001. Registration: April 1, 2017

Registered member

① ID: 0001 Name: Taro Yamada Registration date and time: Current date and time (yyyy / mm / dd) ② ID: 0002 Name: Hanako Suzuki Registration date and time: Current date and time (yyyy / mm / dd) ③ ID: 0003 Name: Takuma Sato Registration date and time: Current date and time (yyyy / mm / dd)

Output all at the end of the program.

Program list

All java files should be created in the package

int type "id" String type "name" Date type "addDate"


The point is to create a Kaiin type dynamic array. Please try to create it while keeping track of where the created data is.

Level 5 music player

The goal is to get used to inheritance and how to use the interface. Estimated travel time: 8 hours


Create two types of music players, the Walkman and the iPod. Both have play / pause / stop functions. Please be able to enter any song name and artist name. Use the main method for the operation.

■ Example of start-of-use message Start using your iPod.

■ Example of song title / artist message Play Ikimonogakari Blue Bird.

In addition, the functional features of the Walkman and iPod are as follows, so please implement them using individual methods.

■ Walkman Play: "Play with explosive sound" Pause: "Wait for 3 minutes" Stop: "Stopped"

■iPod Play: "Play back" Pause: "I'm clever, I'll pause" Stop: "Playback has stopped"

Program list

All java files should be created in the package


There are many programs, but I think it's a good idea to understand each role and proceed. Interface that defines only common behavior Superclass that extracts the process of displaying song titles and artists Class that describes the behavior of the Walkman A class that describes the behavior of the iPod Class that calls process (Main method)


What did you think. I think it will be a good training. Please let me know if there is a shortage or it does not work. We are planning the next web application edition.

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