Build and Run

class MainActivity : AppCompatActivity() {

    private var TAG = "CBL-GS"
    private var cntx: Context = this

    override fun onCreate(savedInstanceState: Bundle?) {

        super.onCreate(savedInstanceState)

        // One-off initialization
        CouchbaseLite.init(cntx)
        Log.i(TAG,"Initialized CBL")

        //
        // <.> Create a database
        Log.i(TAG, "Starting DB")
        val cfg = DatabaseConfigurationFactory.create()
        val database = Database(  "mydb", cfg)

        (1)
        // Create a new document (i.e. a record) in the database.
        var mutableDoc = MutableDocument().setFloat("version", 2.0f).setString("type", "SDK")

        (2)
        // Save it to the database.
        database.save(mutableDoc)

        (3)
        // Retrieve and update a document.
        mutableDoc = database.getDocument(mutableDoc.id)!!.toMutable().setString("language", "Java")
        database.save(mutableDoc)

        (4)
        // Retrieve immutable document and log the document ID
        // generated by the database and some document properties
        val document = database.getDocument(mutableDoc.id)!!
        Log.i(TAG, "Document ID :: ${document.id}")
        Log.i(TAG, "Learning ${document.getString("language")}")

        (5)
        // Create a query to fetch documents of type SDK.
        val rs = QueryBuilder.select(SelectResult.all())
            .from(DataSource.database(database))
            .where(Expression.property("type").equalTo(Expression.string("SDK")))
            .execute()
        Log.i(TAG, "Number of rows :: ${rs.allResults().size}")

        //  (6)
        // OPTIONAL -- if you have Sync Gateway Installed you can try replication too
        // Create a replicator to push and pull changes to and from the cloud.
        // Be sure to hold a reference somewhere to prevent the Replicator from being GCed
        val replicator = Replicator(
            ReplicatorConfigurationFactory.create(
                database = database,
                target = URLEndpoint(URI("ws://localhost:4984/getting-started-db")),
                type = ReplicatorType.PUSH_AND_PULL,
                authenticator = BasicAuthenticator("sync-gateway", "password".toCharArray())
            )
        )

        // Listen to replicator change events.
        // Version using Kotlin Flows to follow shortly ...
        replicator.addChangeListener { change ->
            val err = change.status.error
            if (err != null) {
                Log.i(TAG, "Error code ::  ${err.code}")
            }
        }

        // Start replication.
        replicator.start()

        jsonstuff(argDb = database)

    }


    fun jsonstuff (argDb: Database) {


        var array1: MutableArray = MutableArray().setArray(1, ["a","b"])
        var arrayJson1 = array1.to

    }


}

public class MainActivity extends AppCompatActivity {

  private String TAG = "CBL-GS";
  private Context cntx = this;

  @Override
  protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);


    // One-off initialization
    CouchbaseLite.init(cntx);
    Log.i(TAG,"Initialized CBL");

    //
    (1)
    // Create a database
    Log.i(TAG, "Starting DB");
    DatabaseConfiguration cfg = new DatabaseConfiguration();
    Database database = null;
    try {
            database = new Database(  "mydb", cfg);
    } catch (CouchbaseLiteException e) {
            e.printStackTrace();
    }

    (2)
    // Create a new document (i.e. a record) in the database.
    MutableDocument mutableDoc =
      new MutableDocument().setFloat("version", 2.0f)
                            .setString("type", "SDK");

    (3)
    // Save it to the database.
    try {
            database.save(mutableDoc);
    } catch (CouchbaseLiteException e) {
            e.printStackTrace();
    }

    (4)
    // Retrieve and update a document.
    mutableDoc =
      database.getDocument(mutableDoc.getId())
                            .toMutable()
                            .setString("language", "Java");
    try {
            database.save(mutableDoc);
    } catch (CouchbaseLiteException e) {
            e.printStackTrace();
    }

    (5)
    // Retrieve immutable document and log the document ID
    // generated by the database and some document properties
    Document document = database.getDocument(mutableDoc.getId());
    Log.i(TAG, String.format("Document ID :: %s", document.getId()));
    Log.i(TAG, String.format("Learning :: %s:", document.getString("language")));

    (6)
    // Create a query to fetch documents of type SDK.
    try {
          ResultSet rs =
            QueryBuilder.select(SelectResult.all())
                  .from(DataSource.database(database))
                  .where(Expression.property("type").equalTo(Expression.string("SDK")))
                  .execute();
          Log.i(TAG,
            String.format("Number of rows :: %n",
                          rs.allResults().size()));
    } catch (CouchbaseLiteException e) {
            e.printStackTrace();
    }


    //  (7)
    // OPTIONAL -- if you have Sync Gateway Installed you can try replication too
    // Create a replicator to push and pull changes to and from the cloud.
    // Be sure to hold a reference somewhere to prevent the Replicator from being GCed
    // BasicAuthenticator basAuth = new BasicAuthenticator("sync-gateway", "password".toCharArray());

    //ReplicatorConfiguration replConfig =
    //        new ReplicatorConfiguration(database,
    //                URLEndpoint( URI("ws://localhost:4984/getting-started-db")),
    //                        ReplicatorType.PUSH_AND_PULL,
    //                        basAuth);
    //
    //Replicator replicator = new Replicator(replConfig);

    // Listen to replicator change events.
    // Version using Kotlin Flows to follow shortly ...

    //replicator.addChangeListener(new ReplicatorChangeListener() {
    //             @Override
    //             public void changed(@NonNull ReplicatorChange change) {
    //                     if (change.getStatus().getError() != null) {
    //                             Log.i(TAG, "Error code ::  ${err.code}");
    //                     }
    //             }
    //     });


    // Start replication.
    // replicator.start();

        }
}