Complete Java and Kotlin CI coverage

ROADMAP.md

@@ -31,10 +31,11 @@ Folders without a `test.sh` are skipped until backfilled.
       dotnet. OCaml + Elixir captured locally; F# and Clojure captured from the
       CI log (PR #31). Clojure uses `clojure`, not the interactive `clj` wrapper
       (which printed an rlwrap notice instead of running). All four green on CI.
-- [ ] **Step 5 — Java and Kotlin.** Java: PR #29 (the `java` branch) fixes the
-      numeral typing so PRED works; add test.sh + expected output to that
-      branch, let CI validate it, then merge #29. Kotlin: runner has a JDK;
-      install kotlinc in the workflow.
+- [x] **Step 5 — Java and Kotlin.** Java's numeral fix and `test.sh` landed in
+      PR #29; its expected output was captured from that PR's actual CI run.
+      Kotlin's existing implementation compiles unchanged with Kotlin 2.4.10;
+      its test builds a temporary runnable jar. GitHub's `ubuntu-latest` runner
+      already provides Kotlin 2.4.10 and Java 17, so no installer is needed.
 - [ ] **Step 6 — exotic languages: ArkScript, FatScript, bruijn, Language 84.**
       Each needs its own toolchain acquisition (GitHub releases, cargo/stack
       installs, or building from source). If one is genuinely unobtainable in
@@ -71,5 +72,3 @@ Keep a "wanted" list in the README for languages left open to contributors
       spec or needs a runtime supplement.
 - [ ] Comment on merged PR #6 noting the `Function<Term, Term>` fix, closing
       the loop on the thread there.
-- [ ] Java README still describes an Oracle JDK manual install — point it at
-      apt/Temurin and the test.sh instead.

languages/j/java/README.md

@@ -1,23 +1,22 @@
-# Java 21 Installation Guide
+# Java Lambda Core
 
-## Download Java 21
-Download Java 21 from the official Oracle website:
-[Java 21 Downloads](https://www.oracle.com/in/java/technologies/downloads/#java21)
+This implementation requires a Java Development Kit version 11 or newer.
+Java's source-file mode compiles and runs `LambdaCore.java` directly, so no
+separate build command or external package is needed.
 
-## Installation Steps
-1. Select the appropriate JDK version for your OS (Windows, macOS, or Linux).
-2. Download the installer or compressed archive.
-3. Follow the installation instructions provided by Oracle.
-
-## Verify Installation
-Run the following command to check the installed Java version:
+## Run
 
 ```sh
-java -version
+java LambdaCore.java
 ```
 
-# Run Code
+## Test
+
+From this folder, run:
 
 ```sh
-java LambdaCore.java
+sh test.sh
 ```
+
+The repository's root `run-tests.sh` compares the program's output with
+`expected-output.txt` on every pull request.

languages/j/java/expected-output.txt

@@ -0,0 +1,18 @@
+BOOLEAN TRUE
+BOOLEAN FALSE
+BOOLEAN FALSE
+BOOLEAN TRUE
+BOOLEAN FALSE
+BOOLEAN FALSE
+BOOLEAN FALSE
+BOOLEAN TRUE
+BOOLEAN FALSE
+BOOLEAN TRUE
+BOOLEAN TRUE
+BOOLEAN TRUE
+0
+1
+2
+1
+0
+0

languages/j/java/test.sh

@@ -1 +1,7 @@
-java LambdaCore.java
+#!/bin/sh
+set -eu
+
+command -v java >/dev/null 2>&1 || exit 42
+
+dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
+java "$dir/LambdaCore.java"

languages/k/kotlin/README.md

@@ -1,11 +1,24 @@
-# Kotlin instalation
-Download Kotlin version 2.1.10 ot above from here https://kotlinlang.org/docs/command-line.html
+# Kotlin Lambda Core
 
-# Run code
-```shell
-# build
-kotlinc lambda-core.kt -include-runtime -d lambda-core.jar
+This implementation requires the Kotlin command-line compiler and a Java
+Development Kit. It is tested with Kotlin 2.4.10 and Java 17 or newer; both are
+preinstalled on GitHub's `ubuntu-latest` runner.
+
+## Build and run
 
-#run
+```sh
+kotlinc lambda-core.kt -include-runtime -d lambda-core.jar
 java -jar lambda-core.jar
-```
+```
+
+## Test
+
+From this folder, run:
+
+```sh
+sh test.sh
+```
+
+The test compiles into a temporary directory, runs the resulting jar, and
+removes the build artifact afterward. The repository's root `run-tests.sh`
+compares the output with `expected-output.txt` on every pull request.

languages/k/kotlin/expected-output.txt

@@ -0,0 +1,28 @@
+LOGIC
+----------------
+TRUE/FALSE
+true
+false
+NOT
+false
+true
+AND
+false
+false
+false
+true
+OR
+false
+true
+true
+true
+CHURCH NUMERALS
+---------------
+ZERO/SUCC
+0
+1
+2
+PRED
+2
+1
+0

languages/k/kotlin/test.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+set -eu
+
+command -v kotlinc >/dev/null 2>&1 || exit 42
+command -v java >/dev/null 2>&1 || exit 42
+
+dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
+build_dir=$(mktemp -d)
+trap 'rm -r "$build_dir"' 0 1 2 15
+
+kotlinc "$dir/lambda-core.kt" -include-runtime -d "$build_dir/lambda-core.jar"
+java -jar "$build_dir/lambda-core.jar"