← All coursesjava

Debugging Dojo · Java

Observe. Hypothesize. Fix — objects, collections, and numeric traps.

Progressive Java debugging: off-by-one loops, control-flow chains, lexicographic sort, boxed Integer identity, String equality, list aliasing, floating-point money, index removal, and switch fallthrough.

Intermediate9 lessons~5.5h
First lesson free

Try lesson 1 without an account. Sign in to unlock the remaining 8 lessons and save progress.

Course content

1 · Mindset

  • ○The Loop That Stopped EarlyFree12 min
  • 🔒The Else That Lied15 min
  • 🔒Sorted Like a Dictionary15 min

2 · Sharp edges

  • 🔒Integer == and the Cache22 min
  • 🔒new String Breaks ==18 min
  • 🔒The List That Remembered Too Much18 min
  • 🔒Double Is Not Money20 min
  • 🔒Index Remove Skips Elements22 min

3 · Boss

  • 🔒Switch Fallthrough Surprise20 min