easter_eggs_for_java_loom

• examples re: Project Loom
• usage of egg here is intended as an SSCCE; not a hidden feature

Notes, SEP 2025

• SEP 2025: main branch uses Java 25
• eggs 1-9 work with Bash, Gradle, or Maven
• see also branches: jdk-21, jdk-19 (original)
  • branch jdk-19 has eggs 10, 11, 12 which are now obsolete

Index

• egg_1_max_p_threads
  • demo max # of platform threads
• egg_2_max_v_threads
  • demo max # of virtual threads
• egg_3_legacy_exec
  • illustrates legacy executor/thread pool
• egg_4_virtual_exec
  • illustrates virtual threads via ExecutorService
• egg_5_sc_invoke_all
  • structured concurrency
  • two tasks: foo and bar
    • can be configured to succeed or fail
    • when one task is configured to fail, the other is interrupted
• egg_6_sc_invoke_any
  • structured concurrency
  • task foo and task bar are in a race: first one to complete is used; the other is interrupted
• egg_7_sc_deadline
  • illustrates structured concurrency
  • task foo and task bar take too long and exceed a deadline
    • both are interrupted
• egg_8_sc_custom_invoke_some
  • this egg illustrates structured concurrency
  • create T tasks
    • use a custom StructuredTaskScope.Joiner to define success when n tasks complete
    • if familiar with invokeAny() and invokeAll(), this could be considered invokeSome(n)
  • NOTE: highly contrived and NOT production-ready
• egg_9_sc_fan_in
  • simple client to send messages over a socket to a server
  • NOTE: highly contrived and NOT production-ready
• others
  • egg__11*, egg__12
  • see jdk-19 branch
  • these may not have been moved to jdk-21 and definitely not jdk-25

Notes, SEP 2023

• as of September 2023, these work using Bash but not Gradle or Maven
• GitHub actions are broken, pending availability of JDK 21
• see branch jdk-19 for this repo using JDK 19 (including Gradle and Maven)
• includes examples for virtual threads
• includes examples for structured concurrency, which is "preview" in JDK 21
  • we use sc for "structured concurrency" in the folder names
• see README for each example
• test message