core/org.gnit.lucenekmp.store/Directory

Directory

abstract class Directory : AutoCloseable

A Directory provides an abstraction layer for storing a list of files. A directory contains only files (no sub-folder hierarchy).

Implementing classes must comply with the following:

A file in a directory can be created (.createOutput), appended to, then closed.
A file open for writing may not be available for read access until the corresponding [ ] is closed.
Once a file is created it must only be opened for input (.openInput), or deleted (.deleteFile). Calling .createOutput on an existing file must throw [ ].

NOTE: If your application requires external synchronization, you should not synchronize on the Directory implementation instance as this may cause deadlock; use your own (non-Lucene) objects instead.

See also

ByteBuffersDirectory

FilterDirectory

Inheritors

CompoundDirectory

FileSwitchDirectory

FilterDirectory

Constructors

constructor()

Types

object Companion

Properties

pendingDeletions

abstract val pendingDeletions: MutableSet<String>

Functions

abstract override fun close()

Closes the directory.

open fun copyFrom(from: Directory, src: String, dest: String, context: IOContext)

Copies an existing src file from directory from to a non-existent file dest in this directory. The given IOContext is only used for opening the destination file.

abstract fun createOutput(name: String, context: IOContext): IndexOutput

Creates a new, empty file in the directory and returns an IndexOutput instance for appending data to this file.

createTempOutput

abstract fun createTempOutput(prefix: String, suffix: String, context: IOContext): IndexOutput

Creates a new, empty, temporary file in the directory and returns an IndexOutput instance for appending data to this file.

abstract fun deleteFile(name: String)

Removes an existing file in the directory.

open fun ensureOpen()

Ensures this directory is still open.

abstract fun fileLength(name: String): Long

Returns the byte length of a file in the directory.

abstract fun listAll(): Array<String>

Returns names of all files stored in this directory. The output must be in sorted (UTF-16, java's String.compareTo) order.

abstract fun obtainLock(name: String): Lock

Acquires and returns a Lock for a file with the given name.

openChecksumInput

open fun openChecksumInput(name: String): ChecksumIndexInput

Opens a checksum-computing stream for reading an existing file.

abstract fun openInput(name: String, context: IOContext): IndexInput

Opens a stream for reading an existing file.

abstract fun rename(source: String, dest: String)

Renames source file to dest file where dest must not already exist in the directory.

abstract fun sync(names: MutableCollection<String>)

Ensures that any writes to these files are moved to stable storage (made durable).

abstract fun syncMetaData()

Ensures that directory metadata, such as recent file renames, are moved to stable storage.

open override fun toString(): String