Learn a certification one rule at a time, every answer proven.
The syllabus is split into short drills, one rule each, whose answers were run on the real runtime. Spaced repetition brings back what you are about to forget, so you learn by repetition instead of rereading.
void main() { Path p = Path.of("drafts", "q3", "plan.md"); Path abs = p.toAbsolutePath(); IO.println(abs.isAbsolute() + " " + abs.getFileName());}$ java Main.javatrue plan.md
Learn first, then rehearse
Certification syllabi are long. A study guide covers one once, in prose; a full mock exam tests it all at once and takes about two hours. Learn here first, one rule at a time, then rehearse under exam conditions.
- In this app
Learn one rule at a time
Short daily sessions. Each drill tests one rule, shows what the JVM did and comes back just before you would forget it.
- In this app
Check readiness by domain
Recall per domain shows which objectives still leak, so you study those instead of rereading everything.
- With a full mock-exam bank
Rehearse under exam conditions
Full timed mock exams: long code, mixed traps, the clock. A specialist mock-exam bank is built for this; the few mock exams here check your timing.
Pick your certification
An exam is added only when its answers can be checked on its runtime, or grounded in the vendor's documentation.
- AvailableJDK 17 · 21 · 25
Java OCP
OCP 17 · OCP 21 · OCP 25
Drills run on three JDKs, version traps, a course per exam and timed mock exams.
Open Java OCP - In preparationCPython
Python PCEP and PCAP
Output prediction and code-completion drills, checked on CPython.
Notify me - Plannedterraform
Terraform Associate (004)
Configuration drills checked with terraform validate and terraform console.
Notify me - PlannedSpring Boot tests
Spring Professional
Context and annotation behaviour checked in real Spring Boot tests.
Notify me - PlannedSpark · Delta Lake
Databricks Data Engineer Associate
Transformations checked on local Spark and Delta Lake.
Notify me
How an answer earns its place
Every drill goes through the same pipeline before you see it, whatever the certification.
- Objectivefrom the public syllabus
- Original drill
- Run on the runtimeJDK · CPython · terraform
- Capture the outputstdout, errors, exceptions
- Human reviewsampled and spot-checked
- Published
Original, never dumps
Written from public objectives and official documentation. No leaked or recalled exam questions.
Versioned like the exams
Each drill knows which exam versions it applies to, and where they disagree.
Run again when edited
An edited drill is run again on its runtime before it goes live.
One certification, or all of them
A free slice of every certification. A practice pass is €24 for 120 days, €39 with the course. All-access is €99 a year and includes every certification as it launches.
Questions
Which certification comes next?
Python (PCEP and PCAP) is in preparation. Choose Notify me on a certification to hear when it opens.
How can answers be verified for exams that are not code?
Where a runtime can check the answer, it does. Where it can't, each answer cites the vendor's documentation, with the date it was checked.
Do I keep my progress if I switch certification?
Yes. Progress is kept per certification on your account.