Unit 04

Data Collections

Arrays, ArrayLists, 2D arrays, and the searching, sorting and recursion that make thousands of values as manageable as one.

30–40% of the AP Exam~50–52 CED periods~25–29 blocks here17 topics

AP Computer Science A · members' unit

Data Collections is behind a locked door

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What's in this unit · 39 min read

  1. 4.1 · Ethical and social issues around data collection
  2. 4.2 · Introduction to using data sets
  3. 4.3 · Array creation and access
  4. 4.4 · Array traversals
  5. 4.5 · Implementing array algorithms
  6. 4.6 · Using text files
  7. 4.7 · Wrapper classes
  8. 4.8 · ArrayList methods
  9. 4.9 · ArrayList traversals
  10. 4.10 · Implementing ArrayList algorithms
  11. 4.11 · 2D array creation and access
  12. 4.12 · 2D array traversals
  13. 4.13 · Implementing 2D array algorithms
  14. 4.14 · Searching algorithms
  15. 4.15 · Sorting algorithms
  16. 4.16 · Recursion
  17. 4.17 · Recursive searching and sorting
  18. The projects

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Sources

  • College Board — AP Computer Science A Course and Exam Description, Effective Fall 2025