备份目录中缺少PersistenceTypeDictionary.ptd

Question

使用带有备份目录的Microstream数据库时，除"PersistenceTypeDictionary.ptd“之外的所有文件都将克隆到备份目录中。

当尝试使用备份目录作为源数据库时，Microstream尝试重现此丢失的文件，但我得到一个NullPointerException：

Exception in thread "main" java.lang.RuntimeException: Problem in channel 0
    at one.microstream.storage.types.StorageChannelTask$Abstract.checkForProblems(StorageChannelTask.java:61)
    at one.microstream.storage.types.StorageChannelTask$Abstract.waitOnCompletion(StorageChannelTask.java:123)
    at one.microstream.storage.types.StorageManager$Default.startThreads(StorageManager.java:280)
    at one.microstream.storage.types.StorageManager$Default.internalStartUp(StorageManager.java:449)
    at one.microstream.storage.types.StorageManager$Default.start(StorageManager.java:519)
    at one.microstream.storage.types.StorageManager$Default.start(StorageManager.java:1)
    at one.microstream.storage.types.EmbeddedStorageManager$Default.start(EmbeddedStorageManager.java:233)
    at one.microstream.storage.types.EmbeddedStorageManager$Default.start(EmbeddedStorageManager.java:1)
    at one.microstream.storage.types.EmbeddedStorage.createAndStartStorageManager(EmbeddedStorage.java:580)
    at one.microstream.storage.types.EmbeddedStorage.start(EmbeddedStorage.java:464)
    at com.packenius.book.microstream.examples.backup.Backup_03_CountBackupListEntries.main(Backup_03_CountBackupListEntries.java:12)
Caused by: java.lang.NullPointerException
    at one.microstream.storage.types.StorageFileManager$Default.clearRegisteredFiles(StorageFileManager.java:299)
    at one.microstream.storage.types.StorageFileManager$Default.clearState(StorageFileManager.java:1186)
    at one.microstream.storage.types.StorageFileManager$Default.initializeStorage(StorageFileManager.java:871)
    at one.microstream.storage.types.StorageChannel$Default.initializeStorage(StorageChannel.java:621)
    at one.microstream.storage.types.StorageChannelTaskInitialize$Default.succeed(StorageChannelTaskInitialize.java:197)
    at one.microstream.storage.types.StorageChannelTaskInitialize$Default.succeed(StorageChannelTaskInitialize.java:1)
    at one.microstream.storage.types.StorageChannelSynchronizingTask$AbstractCompletingTask.synchronizedComplete(StorageChannelSynchronizingTask.java:61)
    at one.microstream.storage.types.StorageChannelSynchronizingTask$AbstractCompletingTask.complete(StorageChannelSynchronizingTask.java:109)
    at one.microstream.storage.types.StorageChannelTask$Abstract.processBy(StorageChannelTask.java:213)
    at one.microstream.storage.types.StorageChannel$Default.work(StorageChannel.java:281)
    at one.microstream.storage.types.StorageChannel$Default.run(StorageChannel.java:351)
    at java.lang.Thread.run(Thread.java:748)

我做错了什么？

Answer 1

异常表示类型字典不完整。如果没有正确的类型字典，则无法加载现有的存储。在您的案例中创建的字典只是一个最小的默认类型字典。

不幸的是，我不能说为什么PersistenceTypeDictionary.ptd没有被写入备份目录。