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Java Track Management

This page provides the Exercism community with the information and tools needed to manage the Java track.

Students
207,366
Submissions
3,249,171
Mentoring Discussions
16,253

The Java track needs attention ⚠️

Building

Java syllabus

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Help create the track syllabus: is a set of concepts and learning exercises put together to teach foundational elements of the programming language.

Next goal: Create a complete syllabus with at least 30 concepts. Find out more.
26 concepts being taught
Ba
Basics
41,743 learnt
Bo
Booleans
23,579 learnt
Ar
Arrays
10,950 learnt
Fo
For Loops
10,950 learnt
Fo
For-Each Loops
10,950 learnt
Ge
Generic Types
7,730 learnt
Li
Lists
7,730 learnt
Ex
Exceptions
3,152 learnt
Ch
Chars
7,476 learnt
Cl
Classes
7,219 learnt
Co
Constructors
5,328 learnt
In
Interfaces
3,962 learnt
If
If-Else Statements
11,502 learnt
Nu
Numbers
11,502 learnt
St
Strings
16,033 learnt
Te
Ternary Operators
6,404 learnt
Sw
Switch Statements
4,665 learnt
In
Inheritance
4,228 learnt
En
Enums
2,047 learnt
Nu
Nullability
3,321 learnt
Ra
Randomness
2,252 learnt
Da
Date-Time
2,291 learnt
Me
Method Overloading
1,681 learnt
Bi
Bit Manipulation
2,004 learnt
Se
Sets
1,431 learnt
Ma
Maps
168 learnt
22 active learning exercises
Started
Attempts
Completions
Mentoring requests
Cook Your Lasagna Cook Your Lasagna
68,116
374,271 (avg. 5.5)
41,743 (61.3%)
464 (0.7%)
Annalyn's Infiltration Annalyn's Infiltration
31,588
299,560 (avg. 9.5)
23,579 (74.6%)
301 (1.0%)
Bird Watcher Bird Watcher
13,128
181,138 (avg. 13.8)
10,950 (83.4%)
243 (1.9%)
Karl's Languages Karl's Languages
8,447
46,419 (avg. 5.5)
7,730 (91.5%)
64 (0.8%)
Calculator Conundrum Calculator Conundrum
3,838
53,855 (avg. 14.0)
3,152 (82.1%)
59 (1.5%)
Squeaky Clean Squeaky Clean
11,960
184,795 (avg. 15.5)
7,476 (62.5%)
355 (3.0%)
Elon's Toy Car Elon's Toy Car
7,850
66,172 (avg. 8.4)
7,219 (92.0%)
83 (1.1%)
Need for Speed Need for Speed
6,050
71,668 (avg. 11.8)
5,328 (88.1%)
62 (1.0%)
Remote Control Competition Remote Control Competition
4,999
54,720 (avg. 10.9)
3,962 (79.3%)
76 (1.5%)
Cars, Assemble! Cars, Assemble!
12,795
97,954 (avg. 7.7)
11,502 (89.9%)
229 (1.8%)
Log Levels Log Levels
25,088
226,778 (avg. 9.0)
16,033 (63.9%)
278 (1.1%)
Salary Calculator Salary Calculator
6,883
40,218 (avg. 5.8)
6,404 (93.0%)
38 (0.6%)
Football Match Reports Football Match Reports
4,812
20,209 (avg. 4.2)
4,665 (96.9%)
36 (0.7%)
Wizards and Warriors Wizards and Warriors
4,625
31,543 (avg. 6.8)
4,228 (91.4%)
35 (0.8%)
Logs, Logs, Logs! Logs, Logs, Logs!
2,400
24,663 (avg. 10.3)
2,047 (85.3%)
32 (1.3%)
Tim from Marketing Tim from Marketing
3,532
24,104 (avg. 6.8)
3,321 (94.0%)
51 (1.4%)
Captain's Log Captain's Log
2,402
15,570 (avg. 6.5)
2,252 (93.8%)
13 (0.5%)
Booking Up For Beauty Booking Up For Beauty
2,767
40,135 (avg. 14.5)
2,291 (82.8%)
24 (0.9%)
Wizards and Warriors 2 Wizards and Warriors 2
1,841
15,972 (avg. 8.7)
1,681 (91.3%)
17 (0.9%)
Secrets Secrets
2,312
13,282 (avg. 5.7)
2,004 (86.7%)
4 (0.2%)
Gotta Snatch 'Em All Gotta Snatch 'Em All
1,721
21,701 (avg. 12.6)
1,431 (83.1%)
25 (1.5%)
International Calling Connoisseur International Calling Connoisseur
203
1,914 (avg. 9.4)
168 (82.8%)
1 (0.5%)
1 deprecated learning exercises
Started
Attempts
Completions
Mentoring requests
Play Your Cards! Play Your Cards!
8,676
85,865 (avg. 9.9)
6,852 (79.0%)
121 (1.4%)

Practice Exercises

Learn More

Practice Exercises are exercises designed to allow students to solve an arbitrary problem, with the aim of them making use of the concepts they have learned so far.

Synced primary repo: f193defcf392813d0d6e8573ea2275f0770efcb6 (Updates should be instant)

Next goal: Implement 131 practice exercises. Find out more.
127 active practice exercises
Started
Attempts
Completions
Mentoring requests
Hello World Hello World
151,549
314,799 (avg. 2.1)
96,878 (63.9%)
40 (0.0%)
Leap Leap
5,625
18,445 (avg. 3.3)
4,569 (81.2%)
87 (1.5%)
Reverse String Reverse String
13,939
40,974 (avg. 2.9)
11,622 (83.4%)
315 (2.3%)
Two Fer Two Fer
22,236
70,230 (avg. 3.2)
17,535 (78.9%)
3,918 (17.6%)
Armstrong Numbers Armstrong Numbers
5,635
16,642 (avg. 3.0)
4,389 (77.9%)
127 (2.3%)
Darts Darts
5,776
19,590 (avg. 3.4)
4,491 (77.8%)
59 (1.0%)
D&D Character D&D Character
3,815
28,343 (avg. 7.4)
2,649 (69.4%)
60 (1.6%)
DOT DSL DOT DSL
525
2,595 (avg. 4.9)
317 (60.4%)
4 (0.8%)
Grains Grains
3,715
27,855 (avg. 7.5)
2,983 (80.3%)
46 (1.2%)
High Scores High Scores
1,591
13,828 (avg. 8.7)
1,291 (81.1%)
31 (1.9%)
Resistor Color Resistor Color
5,684
19,735 (avg. 3.5)
4,496 (79.1%)
67 (1.2%)
Resistor Color Duo Resistor Color Duo
3,869
11,919 (avg. 3.1)
3,226 (83.4%)
39 (1.0%)
Resistor Color Trio Resistor Color Trio
912
11,060 (avg. 12.1)
769 (84.3%)
24 (2.6%)
RNA Transcription RNA Transcription
5,961
14,525 (avg. 2.4)
5,002 (83.9%)
229 (3.8%)
Acronym Acronym
3,875
14,609 (avg. 3.8)
3,058 (78.9%)
87 (2.2%)
Difference of Squares Difference of Squares
6,193
20,846 (avg. 3.4)
5,391 (87.0%)
705 (11.4%)
Gigasecond Gigasecond
8,026
18,686 (avg. 2.3)
5,690 (70.9%)
1,343 (16.7%)
Hamming Hamming
7,909
28,664 (avg. 3.6)
6,497 (82.1%)
1,489 (18.8%)
Micro Blog Micro Blog
5,891
33,897 (avg. 5.8)
3,546 (60.2%)
84 (1.4%)
Pangram Pangram
4,871
11,705 (avg. 2.4)
4,030 (82.7%)
168 (3.4%)
Perfect Numbers Perfect Numbers
3,091
11,214 (avg. 3.6)
2,077 (67.2%)
41 (1.3%)
Eliud's Eggs Eliud's Eggs
723
2,488 (avg. 3.4)
643 (88.9%)
7 (1.0%)
Protein Translation Protein Translation
3,144
13,242 (avg. 4.2)
2,474 (78.7%)
45 (1.4%)
Raindrops Raindrops
7,634
19,630 (avg. 2.6)
6,400 (83.8%)
249 (3.3%)
Say Say
2,124
12,632 (avg. 5.9)
835 (39.3%)
34 (1.6%)
Scrabble Score Scrabble Score
5,790
21,043 (avg. 3.6)
4,883 (84.3%)
1,080 (18.7%)
Secret Handshake Secret Handshake
3,829
18,312 (avg. 4.8)
2,906 (75.9%)
464 (12.1%)
Space Age Space Age
3,940
8,215 (avg. 2.1)
3,020 (76.6%)
60 (1.5%)
Collatz Conjecture Collatz Conjecture
1,519
5,573 (avg. 3.7)
1,254 (82.6%)
26 (1.7%)
Diamond Diamond
2,295
10,677 (avg. 4.7)
1,510 (65.8%)
45 (2.0%)
Error Handling Error Handling
1,459
10,431 (avg. 7.1)
809 (55.4%)
5 (0.3%)
ISBN Verifier ISBN Verifier
2,323
9,745 (avg. 4.2)
1,805 (77.7%)
39 (1.7%)
Isogram Isogram
4,662
17,045 (avg. 3.7)
3,741 (80.2%)
166 (3.6%)
Killer Sudoku Helper Killer Sudoku Helper
439
2,416 (avg. 5.5)
243 (55.4%)
11 (2.5%)
Kindergarten Garden Kindergarten Garden
1,016
2,785 (avg. 2.7)
740 (72.8%)
9 (0.9%)
Largest Series Product Largest Series Product
1,658
8,738 (avg. 5.3)
1,314 (79.3%)
19 (1.1%)
Luhn Luhn
2,292
10,397 (avg. 4.5)
1,777 (77.5%)
48 (2.1%)
Matrix Matrix
3,000
15,059 (avg. 5.0)
2,264 (75.5%)
312 (10.4%)
Nth Prime Nth Prime
1,258
4,301 (avg. 3.4)
963 (76.6%)
15 (1.2%)
Proverb Proverb
2,615
7,338 (avg. 2.8)
2,110 (80.7%)
31 (1.2%)
Rotational Cipher Rotational Cipher
2,265
11,246 (avg. 5.0)
1,906 (84.2%)
224 (9.9%)
Saddle Points Saddle Points
1,668
7,080 (avg. 4.2)
1,133 (67.9%)
160 (9.6%)
Sieve Sieve
1,296
3,412 (avg. 2.6)
1,031 (79.6%)
23 (1.8%)
Sum of Multiples Sum of Multiples
1,878
6,300 (avg. 3.4)
1,360 (72.4%)
35 (1.9%)
Triangle Triangle
2,721
10,699 (avg. 3.9)
2,320 (85.3%)
258 (9.5%)
Twelve Days Twelve Days
2,542
13,617 (avg. 5.4)
1,912 (75.2%)
32 (1.3%)
Variable Length Quantity Variable Length Quantity
576
1,794 (avg. 3.1)
291 (50.5%)
1 (0.2%)
Yacht Yacht
1,474
6,467 (avg. 4.4)
968 (65.7%)
29 (2.0%)
Allergies Allergies
1,179
3,904 (avg. 3.3)
910 (77.2%)
25 (2.1%)
Atbash Cipher Atbash Cipher
701
3,551 (avg. 5.1)
553 (78.9%)
7 (1.0%)
Bob Bob
1,947
11,124 (avg. 5.7)
1,590 (81.7%)
57 (2.9%)
Flatten Array Flatten Array
1,589
7,125 (avg. 4.5)
1,194 (75.1%)
134 (8.4%)
Conway's Game of Life Conway's Game of Life
216
906 (avg. 4.2)
117 (54.2%)
0 (0.0%)
Grep Grep
585
2,395 (avg. 4.1)
310 (53.0%)
5 (0.9%)
Knapsack Knapsack
824
3,750 (avg. 4.6)
489 (59.3%)
9 (1.1%)
Ledger Ledger
268
1,805 (avg. 6.7)
144 (53.7%)
6 (2.2%)
Matching Brackets Matching Brackets
677
2,414 (avg. 3.6)
485 (71.6%)
8 (1.2%)
Nucleotide Count Nucleotide Count
2,021
5,715 (avg. 2.8)
1,810 (89.6%)
89 (4.4%)
Pascal's Triangle Pascal's Triangle
709
1,772 (avg. 2.5)
493 (69.5%)
4 (0.6%)
Phone Number Phone Number
1,385
7,094 (avg. 5.1)
1,073 (77.5%)
23 (1.7%)
Pig Latin Pig Latin
2,612
10,787 (avg. 4.1)
1,431 (54.8%)
76 (2.9%)
Prime Factors Prime Factors
793
2,386 (avg. 3.0)
596 (75.2%)
11 (1.4%)
Robot Name Robot Name
1,694
9,547 (avg. 5.6)
1,409 (83.2%)
137 (8.1%)
Run-Length Encoding Run-Length Encoding
571
2,109 (avg. 3.7)
399 (69.9%)
9 (1.6%)
Series Series
913
2,505 (avg. 2.7)
751 (82.3%)
11 (1.2%)
Square Root Square Root
391
1,186 (avg. 3.0)
306 (78.3%)
7 (1.8%)
Word Count Word Count
2,735
15,661 (avg. 5.7)
2,094 (76.6%)
212 (7.8%)
State Of Tic Tac Toe State Of Tic Tac Toe
181
1,217 (avg. 6.7)
106 (58.6%)
5 (2.8%)
Affine Cipher Affine Cipher
301
1,976 (avg. 6.6)
191 (63.5%)
3 (1.0%)
All Your Base All Your Base
435
1,928 (avg. 4.4)
287 (66.0%)
2 (0.5%)
Alphametics Alphametics
486
1,811 (avg. 3.7)
183 (37.7%)
3 (0.6%)
Bank Account Bank Account
1,470
8,075 (avg. 5.5)
1,050 (71.4%)
89 (6.1%)
Binary Search Binary Search
1,209
6,687 (avg. 5.5)
918 (75.9%)
93 (7.7%)
Bottle Song Bottle Song
601
5,896 (avg. 9.8)
384 (63.9%)
18 (3.0%)
Bowling Bowling
844
6,034 (avg. 7.1)
371 (44.0%)
11 (1.3%)
ETL ETL
1,723
2,504 (avg. 1.5)
1,581 (91.8%)
128 (7.4%)
Food Chain Food Chain
809
2,950 (avg. 3.6)
546 (67.5%)
10 (1.2%)
Grade School Grade School
729
2,298 (avg. 3.2)
535 (73.4%)
21 (2.9%)
House House
882
3,252 (avg. 3.7)
646 (73.2%)
9 (1.0%)
Linked List Linked List
1,293
5,487 (avg. 4.2)
930 (71.9%)
75 (5.8%)
Minesweeper Minesweeper
763
2,697 (avg. 3.5)
496 (65.0%)
8 (1.0%)
Parallel Letter Frequency Parallel Letter Frequency
657
3,010 (avg. 4.6)
409 (62.3%)
12 (1.8%)
Queen Attack Queen Attack
1,964
7,405 (avg. 3.8)
705 (35.9%)
33 (1.7%)
Rail Fence Cipher Rail Fence Cipher
310
1,188 (avg. 3.8)
181 (58.4%)
1 (0.3%)
REST API REST API
576
2,506 (avg. 4.4)
131 (22.7%)
4 (0.7%)
Robot Simulator Robot Simulator
720
2,274 (avg. 3.2)
451 (62.6%)
10 (1.4%)
Roman Numerals Roman Numerals
1,076
3,208 (avg. 3.0)
798 (74.2%)
15 (1.4%)
Spiral Matrix Spiral Matrix
520
1,214 (avg. 2.3)
313 (60.2%)
5 (1.0%)
Tournament Tournament
554
2,412 (avg. 4.4)
287 (51.8%)
10 (1.8%)
Transpose Transpose
480
2,203 (avg. 4.6)
253 (52.7%)
2 (0.4%)
Wordy Wordy
506
2,178 (avg. 4.3)
290 (57.3%)
6 (1.2%)
Anagram Anagram
3,047
9,574 (avg. 3.1)
2,186 (71.7%)
111 (3.6%)
Binary Search Tree Binary Search Tree
553
2,110 (avg. 3.8)
308 (55.7%)
7 (1.3%)
Clock Clock
464
1,858 (avg. 4.0)
308 (66.4%)
2 (0.4%)
Crypto Square Crypto Square
388
1,556 (avg. 4.0)
261 (67.3%)
2 (0.5%)
Dominoes Dominoes
1,005
2,852 (avg. 2.8)
244 (24.3%)
9 (0.9%)
Go Counting Go Counting
437
1,129 (avg. 2.6)
147 (33.6%)
0 (0.0%)
Markdown Markdown
827
1,702 (avg. 2.1)
326 (39.4%)
14 (1.7%)
Meetup Meetup
825
2,102 (avg. 2.5)
652 (79.0%)
11 (1.3%)
Poker Poker
673
2,121 (avg. 3.2)
194 (28.8%)
4 (0.6%)
SGF Parsing SGF Parsing
96
1,188 (avg. 12.4)
53 (55.2%)
2 (2.1%)
Simple Linked List Simple Linked List
642
3,171 (avg. 4.9)
390 (60.7%)
8 (1.2%)
Sublist Sublist
403
1,387 (avg. 3.4)
260 (64.5%)
0 (0.0%)
Tree Building Tree Building
261
568 (avg. 2.2)
113 (43.3%)
2 (0.8%)
Two Bucket Two Bucket
321
895 (avg. 2.8)
137 (42.7%)
3 (0.9%)
Word Search Word Search
801
2,248 (avg. 2.8)
237 (29.6%)
5 (0.6%)
Zebra Puzzle Zebra Puzzle
1,865
1,579 (avg. 0.8)
324 (17.4%)
5 (0.3%)
Zipper Zipper
241
657 (avg. 2.7)
102 (42.3%)
0 (0.0%)
Book Store Book Store
466
1,307 (avg. 2.8)
163 (35.0%)
5 (1.1%)
Change Change
444
2,177 (avg. 4.9)
176 (39.6%)
4 (0.9%)
Circular Buffer Circular Buffer
495
1,722 (avg. 3.5)
299 (60.4%)
4 (0.8%)
Complex Numbers Complex Numbers
488
1,594 (avg. 3.3)
301 (61.7%)
11 (2.3%)
Connect Connect
286
1,456 (avg. 5.1)
146 (51.0%)
7 (2.4%)
Hangman Hangman
267
669 (avg. 2.5)
63 (23.6%)
5 (1.9%)
List Ops List Ops
429
1,860 (avg. 4.3)
232 (54.1%)
8 (1.9%)
Mazy Mice Mazy Mice
75
494 (avg. 6.6)
31 (41.3%)
0 (0.0%)
OCR Numbers OCR Numbers
330
641 (avg. 1.9)
169 (51.2%)
3 (0.9%)
Palindrome Products Palindrome Products
391
1,127 (avg. 2.9)
203 (51.9%)
3 (0.8%)
POV POV
90
617 (avg. 6.9)
47 (52.2%)
1 (1.1%)
Rational Numbers Rational Numbers
380
2,158 (avg. 5.7)
208 (54.7%)
4 (1.1%)
React React
139
748 (avg. 5.4)
47 (33.8%)
1 (0.7%)
Rectangles Rectangles
299
776 (avg. 2.6)
146 (48.8%)
3 (1.0%)
Simple Cipher Simple Cipher
456
1,422 (avg. 3.1)
291 (63.8%)
7 (1.5%)
Forth Forth
455
1,484 (avg. 3.3)
179 (39.3%)
11 (2.4%)
Pythagorean Triplet Pythagorean Triplet
964
6,062 (avg. 6.3)
416 (43.2%)
5 (0.5%)
Custom Set Custom Set
444
1,503 (avg. 3.4)
204 (45.9%)
2 (0.5%)
Satellite Satellite
326
776 (avg. 2.4)
124 (38.0%)
2 (0.6%)
8 deprecated practice exercises
Started
Attempts
Completions
Mentoring requests
Accumulate Accumulate
110
138 (avg. 1.3)
107 (97.3%)
5 (4.5%)
Beer Song Beer Song
867
3,375 (avg. 3.9)
663 (76.5%)
15 (1.7%)
Binary Binary
136
180 (avg. 1.3)
133 (97.8%)
6 (4.4%)
Diffie-Hellman Diffie-Hellman
228
327 (avg. 1.4)
117 (51.3%)
2 (0.9%)
Hexadecimal Hexadecimal
58
73 (avg. 1.3)
55 (94.8%)
7 (12.1%)
Octal Octal
59
69 (avg. 1.2)
56 (94.9%)
2 (3.4%)
Strain Strain
111
141 (avg. 1.3)
107 (96.4%)
5 (4.5%)
Trinary Trinary
71
83 (avg. 1.2)
68 (95.8%)
1 (1.4%)
4 unimplemented practice exercises
Baffling Birthdays Baffling Birthdays
View dataThe link opens in a new window or tab
PaaS I/O PaaS I/O
View dataThe link opens in a new window or tab
Relative Distance Relative Distance
View dataThe link opens in a new window or tab
Swift Scheduling Swift Scheduling
View dataThe link opens in a new window or tab
1 foregone practice exercise
Lens Person Lens Person
View dataThe link opens in a new window or tab

Programming Tags

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Help manage the tags used to group, filter and recommend solutions, approaches and articles.

0 tags

Test Runner

Learn More

Create Test Runners that have the single responsibility of taking a solution, running all tests and returning a standardized output.

Current version: 67629f072af02ffe40b27aa6f3fa41b71d188cb7 (Takes up to 10 mins to deploy)

Total Test Runner Runs
3,174,169
Test Run Pass Rate
17.4% (551425)
Test Run Fail Rate
37.7% (1198058)
Test Run Error Rate
44.9% (1424686)

Representer

Learn More

Build a Representer: a bit of code that has the single responsibility of taking a solution and returning a normalized representation of it.

Current version: 4c426e72f23bc01160b2b06807c4c154c79c4dee (Takes up to 10 mins to deploy)

Total Representer Runs
696,368
Total Representation Comments Made
4
Feedback Given Frequency
0.0%

Analyzer

Learn More

Build an Analyzer for Java: Exercism's analyzers automatically assess student's submissions and provide mentor-style commentary.

Current version: 2e979a5bb3bc0cedbc49ebc275697fdba492667a (Takes up to 10 mins to deploy)

Total Analyzer Runs
412,062
Total Analysis Comments Made
232,373
Feedback Given Frequency
3.3%