Platform neutral export/import tool was added.

environment/src/main/java/jetbrains/exodus/env/EnvExportImport.java

@@ -0,0 +1,129 @@
+package jetbrains.exodus.env;
+
+import jetbrains.exodus.ArrayByteIterable;
+
+import java.io.*;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+
+public class EnvExportImport {
+    public static void exportEnvironment(Path envPath, EnvironmentConfig envConf, Path exportPath) {
+        try (Environment env = Environments.newInstance(envPath.toFile(), envConf)) {
+            env.executeInReadonlyTransaction(txn -> {
+                if (Files.exists(exportPath)) {
+                    throw new IllegalStateException("Export file already exists: " + exportPath);
+                }
+
+                Path parent = exportPath.getParent();
+                if (parent != null) {
+                    try {
+                        Files.createDirectories(parent);
+                    } catch (IOException e) {
+                        throw new RuntimeException(e);
+                    }
+                }
+                try {
+                    Files.createFile(exportPath);
+                } catch (IOException e) {
+                    throw new RuntimeException(e);
+                }
+
+                try {
+                    try (OutputStream outputStream = Files.newOutputStream(exportPath)) {
+                        try (DataOutputStream dataOutputStream = new DataOutputStream(outputStream)) {
+                            final List<String> stores = env.getAllStoreNames(txn);
+
+                            for (String storeName : stores) {
+                                final Store store = env.openStore(storeName, StoreConfig.USE_EXISTING, txn);
+
+                                int entryCount = 0;
+                                try (Cursor cursor = store.openCursor(txn)) {
+                                    while (cursor.getNext()) {
+                                        dataOutputStream.writeUTF(storeName);
+                                        dataOutputStream.writeUTF(store.getConfig().name());
+
+
+                                        byte[] key = cursor.getKey().getBytesUnsafe();
+
+                                        dataOutputStream.writeInt(cursor.getKey().getLength());
+                                        dataOutputStream.writeInt(key.length);
+                                        dataOutputStream.write(key);
+
+                                        byte[] value = cursor.getValue().getBytesUnsafe();
+
+                                        dataOutputStream.writeInt(cursor.getValue().getLength());
+                                        dataOutputStream.writeInt(value.length);
+
+                                        dataOutputStream.write(value);
+
+                                        entryCount++;
+                                    }
+                                }
+
+                                System.out.println("Exported " + entryCount + " entries from store " + storeName);
+                            }
+                        }
+                    }
+                } catch (IOException e) {
+                    throw new RuntimeException(e);
+                }
+            });
+        }
+    }
+
+    public static void importEnvironment(Path envPath, EnvironmentConfig envConf, Path importPath) {
+        try (Environment env = Environments.newInstance(envPath.toFile(), envConf)) {
+            env.executeInTransaction(txn -> {
+                try {
+                    try (InputStream inputStream = Files.newInputStream(importPath)) {
+                        try (DataInputStream dataInputStream = new DataInputStream(inputStream)) {
+                            String currentStoreName = null;
+                            Store currentStore = null;
+                            int entryCount = 0;
+                            try {
+                                while (true) {
+                                    final String storeName = dataInputStream.readUTF();
+                                    String configName = dataInputStream.readUTF();
+
+                                    final StoreConfig storeConfig = StoreConfig.valueOf(configName);
+                                    if (currentStoreName == null) {
+                                        currentStoreName = storeName;
+                                        currentStore = env.openStore(storeName, storeConfig, txn);
+                                    } else if (!currentStoreName.equals(storeName)) {
+                                        System.out.println("Imported " + entryCount + " entries to store " + currentStoreName);
+
+                                        currentStoreName = storeName;
+                                        currentStore = env.openStore(storeName, storeConfig, txn);
+                                        entryCount = 0;
+                                    }
+
+                                    final int keyLength = dataInputStream.readInt();
+                                    final int rawKeyLength = dataInputStream.readInt();
+                                    final byte[] key = new byte[rawKeyLength];
+                                    dataInputStream.readFully(key);
+
+                                    final int valueLength = dataInputStream.readInt();
+                                    final int rawValueLength = dataInputStream.readInt();
+                                    final byte[] value = new byte[rawValueLength];
+                                    dataInputStream.readFully(value);
+
+                                    currentStore.put(txn, new ArrayByteIterable(key, keyLength),
+                                            new ArrayByteIterable(value, valueLength));
+                                    entryCount += 1;
+                                }
+                            } catch (EOFException e) {
+                                // end of file
+                            }
+                            if (currentStoreName != null) {
+                                System.out.println("Imported " + entryCount + " entries to store " + currentStoreName);
+                            }
+                        }
+                    }
+                } catch (IOException e) {
+                    throw new RuntimeException(e);
+                }
+            });
+        }
+    }
+}