Update Example.java, LLDatabaseConnection.java, and 4 more files...

src/example/java/it.cavallium.dbengine.client/Example.java

@@ -0,0 +1,17 @@
+package it.cavallium.dbengine.client;
+
+import it.cavallium.dbengine.database.Column;
+import it.cavallium.dbengine.database.disk.LLLocalDatabaseConnection;
+import java.nio.file.Path;
+import java.util.List;
+
+public class Example {
+
+	public static void main(String[] args) {
+		System.out.println("Test");
+		new LLLocalDatabaseConnection(Path.of("/tmp/"), true)
+				.connect()
+				.flatMap(conn -> conn.getDatabase("testdb", List.of(Column.hashMap("testmap")), false))
+				.block();
+	}
+}

src/main/java/it/cavallium/dbengine/database/LLDatabaseConnection.java

@@ -1,23 +1,22 @@
 package it.cavallium.dbengine.database;
 
 import it.cavallium.dbengine.database.analyzer.TextFieldsAnalyzer;
-import java.io.IOException;
 import java.time.Duration;
 import java.util.List;
 import reactor.core.publisher.Mono;
 
 public interface LLDatabaseConnection {
 
-	Mono<Void> connect();
+	Mono<? extends LLDatabaseConnection> connect();
 
-	LLKeyValueDatabase getDatabase(String name, List<Column> columns, boolean lowMemory) throws IOException;
+	Mono<? extends LLKeyValueDatabase> getDatabase(String name, List<Column> columns, boolean lowMemory);
 
-	LLLuceneIndex getLuceneIndex(String name,
+	Mono<? extends LLLuceneIndex> getLuceneIndex(String name,
 			int instancesCount,
 			TextFieldsAnalyzer textFieldsAnalyzer,
 			Duration queryRefreshDebounceTime,
 			Duration commitDebounceTime,
-			boolean lowMemory) throws IOException;
+			boolean lowMemory);
 
 	Mono<Void> disconnect();
 }

src/main/java/it/cavallium/dbengine/database/collections/SubStageGetterMapDeep.java

@@ -7,24 +7,35 @@ import org.jetbrains.annotations.Nullable;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
-public class SubStageGetterMapDeep<U, US extends DatabaseStage<U>> implements
+public class SubStageGetterMapDeep<T, U, US extends DatabaseStage<U>> implements
-		SubStageGetter<Map<byte[], U>, DatabaseStageEntry<Map<byte[], U>>> {
+		SubStageGetter<Map<T, U>, DatabaseStageEntry<Map<T, U>>> {
 
 	private final SubStageGetter<U, US> subStageGetter;
+	private final FixedLengthSerializer<T> keySerializer;
 	private final int keyLength;
 	private final int keyExtLength;
 
-	public SubStageGetterMapDeep(SubStageGetter<U, US> subStageGetter, int keyLength, int keyExtLength) {
+	public SubStageGetterMapDeep(SubStageGetter<U, US> subStageGetter,
+			FixedLengthSerializer<T> keySerializer,
+			int keyLength,
+			int keyExtLength) {
 		this.subStageGetter = subStageGetter;
+		this.keySerializer = keySerializer;
 		this.keyLength = keyLength;
 		this.keyExtLength = keyExtLength;
 	}
 
 	@Override
-	public Mono<DatabaseStageEntry<Map<byte[], U>>> subStage(LLDictionary dictionary,
+	public Mono<DatabaseStageEntry<Map<T, U>>> subStage(LLDictionary dictionary,
 			@Nullable CompositeSnapshot snapshot,
 			byte[] prefixKey,
 			Flux<byte[]> keyFlux) {
-		return Mono.just(new DatabaseMapDictionary<>(dictionary, subStageGetter, prefixKey, keyLength, keyExtLength));
+		return Mono.just(new DatabaseMapDictionary<>(dictionary,
+				subStageGetter,
+				keySerializer,
+				prefixKey,
+				keyLength,
+				keyExtLength
+		));
 	}
 }

src/main/java/it/cavallium/dbengine/database/disk/LLLocalDatabaseConnection.java

@@ -1,15 +1,14 @@
 package it.cavallium.dbengine.database.disk;
 
-import java.io.IOException;
+import it.cavallium.dbengine.database.Column;
+import it.cavallium.dbengine.database.LLDatabaseConnection;
+import it.cavallium.dbengine.database.LLLuceneIndex;
+import it.cavallium.dbengine.database.analyzer.TextFieldsAnalyzer;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.time.Duration;
 import java.util.LinkedList;
 import java.util.List;
-import it.cavallium.dbengine.database.Column;
-import it.cavallium.dbengine.database.LLDatabaseConnection;
-import it.cavallium.dbengine.database.LLLuceneIndex;
-import it.cavallium.dbengine.database.analyzer.TextFieldsAnalyzer;
 import reactor.core.publisher.Mono;
 import reactor.core.scheduler.Schedulers;
 
@@ -24,48 +23,59 @@ public class LLLocalDatabaseConnection implements LLDatabaseConnection {
 	}
 
 	@Override
-	public Mono<Void> connect() {
+	public Mono<LLDatabaseConnection> connect() {
 		return Mono
-				.<Void>fromCallable(() -> {
+				.<LLDatabaseConnection>fromCallable(() -> {
 					if (Files.notExists(basePath)) {
 						Files.createDirectories(basePath);
 					}
-					return null;
+					return this;
 				})
 				.subscribeOn(Schedulers.boundedElastic());
 	}
 
 	@Override
-	public LLLocalKeyValueDatabase getDatabase(String name, List<Column> columns, boolean lowMemory) throws IOException {
+	public Mono<LLLocalKeyValueDatabase> getDatabase(String name, List<Column> columns, boolean lowMemory) {
-		return new LLLocalKeyValueDatabase(name, basePath.resolve("database_" + name), columns, new LinkedList<>(),
+		return Mono
-				crashIfWalError, lowMemory);
+				.<LLLocalKeyValueDatabase>fromCallable(() -> new LLLocalKeyValueDatabase(name,
+						basePath.resolve("database_" + name),
+						columns,
+						new LinkedList<>(),
+						crashIfWalError,
+						lowMemory
+				))
+				.subscribeOn(Schedulers.boundedElastic());
 	}
 
 	@Override
-	public LLLuceneIndex getLuceneIndex(String name,
+	public Mono<LLLuceneIndex> getLuceneIndex(String name,
 			int instancesCount,
 			TextFieldsAnalyzer textFieldsAnalyzer,
 			Duration queryRefreshDebounceTime,
 			Duration commitDebounceTime,
-			boolean lowMemory) throws IOException {
+			boolean lowMemory) {
-		if (instancesCount != 1) {
+		return Mono
-			return new LLLocalMultiLuceneIndex(basePath.resolve("lucene"),
+				.fromCallable(() -> {
-					name,
+					if (instancesCount != 1) {
-					instancesCount,
+						return new LLLocalMultiLuceneIndex(basePath.resolve("lucene"),
-					textFieldsAnalyzer,
+								name,
-					queryRefreshDebounceTime,
+								instancesCount,
-					commitDebounceTime,
+								textFieldsAnalyzer,
-					lowMemory
+								queryRefreshDebounceTime,
-			);
+								commitDebounceTime,
-		} else {
+								lowMemory
-			return new LLLocalLuceneIndex(basePath.resolve("lucene"),
+						);
-					name,
+					} else {
-					textFieldsAnalyzer,
+						return new LLLocalLuceneIndex(basePath.resolve("lucene"),
-					queryRefreshDebounceTime,
+								name,
-					commitDebounceTime,
+								textFieldsAnalyzer,
-					lowMemory
+								queryRefreshDebounceTime,
-			);
+								commitDebounceTime,
-		}
+								lowMemory
+						);
+					}
+				})
+				.subscribeOn(Schedulers.boundedElastic());
 	}
 
 	@Override

src/main/java/it/cavallium/dbengine/database/disk/LLLocalKeyValueDatabase.java

@@ -61,6 +61,8 @@ public class LLLocalKeyValueDatabase implements LLKeyValueDatabase {
 		Options options = openRocksDb(path, crashIfWalError, lowMemory);
 		try {
 			List<ColumnFamilyDescriptor> descriptors = new LinkedList<>();
+			descriptors
+					.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
 			for (Column column : columns) {
 				descriptors
 						.add(new ColumnFamilyDescriptor(column.getName().getBytes(StandardCharsets.US_ASCII)));
@@ -240,6 +242,7 @@ public class LLLocalKeyValueDatabase implements LLKeyValueDatabase {
 		});
 
 		List<ColumnFamilyDescriptor> descriptors = new LinkedList<>();
+		descriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
 		for (byte[] existingColumnFamily : existingColumnFamilies) {
 			descriptors.add(new ColumnFamilyDescriptor(existingColumnFamily));
 		}

src/test/java/it/cavallium/dbengine/client/Database.java

@@ -1,3 +1,5 @@
 package it.cavallium.dbengine.client;
 
-public class Database {}
+public class Database {
+
+}