Java binding

// build.gradle.kts
repositories {
    mavenCentral()
}

dependencies {
    implementation("com.offlineprotocol:offline-protocol-java:0.30.0")
}

java --enable-native-access=ALL-UNNAMED \
     -Djava.library.path=/path/to/library/directory \
     -jar app.jar

import com.offlineprotocol.sdk.*;

// The generated record has no defaults: every field is spelled out, in the
// order of the definition (ProtocolConfig in offline_protocol.udl). Optional
// fields (mesh relay, custody) take null.
ProtocolConfig config = new ProtocolConfig(
    "com.example.app", "default",
    false, false, true, false, false, false, // ble, wifi direct, internet, reticulum, nostr, prefer online
    (byte) 8, true, true, true, true,        // ttl, encryption, auto key exchange, store pending, require encryption
    64L, 4096L, 60_000L, OverflowPolicy.DROP_OLDEST,
    false, 256, true, true, false, false,
    true, true, true, false, true, true, true,
    null, null,
    true, true, true);

try (OfflineProtocol engine = new OfflineProtocol(config)) {
    // Storage before start(). The store key seals key material at rest;
    // keep it out of the source.
    engine.initializeMlsWithFileStores("/var/lib/app/mls", "/var/lib/app/state", storeKey32Bytes);

    engine.setEventCallback(json -> queue.add(json)); // copy and return; never call the engine from here
    engine.start();
    System.out.println("this device is " + engine.localAddress());

    try {
        engine.sendMessage("off1...", "hi", MessagePriority.MEDIUM, null);
    } catch (ProtocolException.EncryptFailed e) {
        // each engine refusal is its own exception type
    }
    engine.stop();
}