feat(jni): list the editions a session knows

java/vortex-jni/src/main/java/dev/vortex/api/Session.java

@@ -6,6 +6,7 @@
 import com.google.common.base.Preconditions;
 import dev.vortex.VortexCleaner;
 import dev.vortex.jni.NativeSession;
+import java.util.Set;
 
 /**
  * Handle to a native Vortex session. The session owns a current-thread async runtime and is the entry point for opening
@@ -40,6 +41,14 @@ public void enableEdition(String edition) {
         NativeSession.enableEdition(pointer, edition);
     }
 
+    /**
+     * The name of every edition this session knows, for example {@code core2025.10.0}. Each one is a name
+     * {@link #enableEdition} accepts.
+     */
+    public Set<String> knownEditions() {
+        return Set.of(NativeSession.knownEditions(pointer));
+    }
+
     /** Internal: returns the native pointer. Do not free directly. */
     public long nativePointer() {
         return pointer;

java/vortex-jni/src/main/java/dev/vortex/jni/NativeSession.java

@@ -22,4 +22,7 @@ private NativeSession() {}
      * this call. Throws a {@link RuntimeException} if the edition is not known.
      */
     public static native void enableEdition(long pointer, String edition);
+
+    /** The name of every edition the session knows, each one a name {@link #enableEdition} accepts. */
+    public static native String[] knownEditions(long pointer);
 }

java/vortex-jni/src/test/java/dev/vortex/api/SessionTest.java

@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: Copyright the Vortex contributors
+
+package dev.vortex.api;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.Set;
+import org.junit.jupiter.api.Test;
+
+public final class SessionTest {
+
+    @Test
+    public void knownEditionsIncludeTheCoreEditionsAndTheListLayoutEdition() {
+        Set<String> known = Session.create().knownEditions();
+
+        assertTrue(known.contains("core2025.10.0"), known::toString);
+        assertTrue(known.contains("core2026.08.3"), known::toString);
+        assertTrue(known.contains("qc2026.11.0"), known::toString);
+        assertFalse(known.contains("core2099.01.0"), known::toString);
+    }
+
+    @Test
+    public void everyKnownEditionCanBeEnabled() {
+        Session session = Session.create();
+
+        for (String edition : session.knownEditions()) {
+            assertDoesNotThrow(() -> session.enableEdition(edition), edition);
+        }
+    }
+
+    @Test
+    public void anEditionThatIsntKnownCantBeEnabled() {
+        Session session = Session.create();
+
+        assertFalse(session.knownEditions().contains("core2099.01.0"));
+        assertThrows(RuntimeException.class, () -> session.enableEdition("core2099.01.0"));
+    }
+}

vortex-jni/src/session.rs

@@ -5,8 +5,10 @@
 
 use jni::EnvUnowned;
 use jni::objects::JClass;
+use jni::objects::JObject;
 use jni::objects::JString;
 use jni::sys::jlong;
+use jni::sys::jobjectArray;
 use vortex::VortexSessionDefault;
 use vortex::editions::CORE_2026_08_3;
 use vortex::editions::EditionSessionExt;
@@ -87,3 +89,30 @@ pub extern "system" fn Java_dev_vortex_jni_NativeSession_enableEdition(
         Ok(())
     })
 }
+
+/// Returns the name of every edition the session knows, for example `core2025.10.0`, as a
+/// `String[]`. Each one is a name `enableEdition` accepts.
+#[unsafe(no_mangle)]
+pub extern "system" fn Java_dev_vortex_jni_NativeSession_knownEditions(
+    mut env: EnvUnowned,
+    _class: JClass,
+    pointer: jlong,
+) -> jobjectArray {
+    try_or_throw(&mut env, |env| {
+        // SAFETY: pointer must have been created by `newSession` and not yet freed.
+        let session = unsafe { session_ref(pointer) };
+        let editions = session.editions().editions();
+        let names = env.new_object_array(
+            i32::try_from(editions.len())
+                .map_err(|_| vortex_err!("edition count exceeds Java array range"))?,
+            jni::jni_str!("java/lang/String"),
+            JObject::null(),
+        )?;
+        for (index, edition) in editions.iter().enumerate() {
+            let name = env.new_string(edition.id.to_string())?;
+            names.set_element(env, index, &name)?;
+            env.delete_local_ref(name);
+        }
+        Ok(names.into_raw())
+    })
+}