java.lang.Object
- org.apache.lucene.store.Directory
- - org.apache.lucene.store.BaseDirectory
  - - org.apache.lucene.store.ByteBuffersDirectory

All Implemented Interfaces:

Closeable, AutoCloseable
```
public final class ByteBuffersDirectory
extends BaseDirectory
```
A ByteBuffer-based Directory implementation that can be used to store index files on the heap.
Important: Note that MMapDirectory is nearly always a better choice as it uses OS caches more effectively (through memory-mapped buffers). A heap-based directory like this one can have the advantage in case of ephemeral, small, short-lived indexes when disk syncs provide an additional overhead.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Field Summary

Fields
Modifier and Type	Field	Description
`static BiFunction<String,ByteBuffersDataOutput,IndexInput>`	`OUTPUT_AS_BYTE_ARRAY`
`static BiFunction<String,ByteBuffersDataOutput,IndexInput>`	`OUTPUT_AS_MANY_BUFFERS`
`static BiFunction<String,ByteBuffersDataOutput,IndexInput>`	`OUTPUT_AS_MANY_BUFFERS_LUCENE`
`static BiFunction<String,ByteBuffersDataOutput,IndexInput>`	`OUTPUT_AS_ONE_BUFFER`

Fields inherited from class org.apache.lucene.store.BaseDirectory
isOpen, lockFactory

Constructor Summary

Constructors
Constructor	Description
`ByteBuffersDirectory()`
`ByteBuffersDirectory(LockFactory lockFactory)`
`ByteBuffersDirectory(LockFactory factory, Supplier<ByteBuffersDataOutput> bbOutputSupplier, BiFunction<String,ByteBuffersDataOutput,IndexInput> outputToInput)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`close()`	Closes the directory.
`IndexOutput`	`createOutput(String name, IOContext context)`	Creates a new, empty file in the directory and returns an `IndexOutput` instance for appending data to this file.
`IndexOutput`	`createTempOutput(String prefix, String suffix, IOContext context)`	Creates a new, empty, temporary file in the directory and returns an `IndexOutput` instance for appending data to this file.
`void`	`deleteFile(String name)`	Removes an existing file in the directory.
`boolean`	`fileExists(String name)`
`long`	`fileLength(String name)`	Returns the byte length of a file in the directory.
`Set<String>`	`getPendingDeletions()`	Returns a set of files currently pending deletion in this directory.
`String[]`	`listAll()`	Returns names of all files stored in this directory.
`IndexInput`	`openInput(String name, IOContext context)`	Opens a stream for reading an existing file.
`void`	`rename(String source, String dest)`	Renames `source` file to `dest` file where `dest` must not already exist in the directory.
`void`	`sync(Collection<String> names)`	Ensures that any writes to these files are moved to stable storage (made durable).
`void`	`syncMetaData()`	Ensures that directory metadata, such as recent file renames, are moved to stable storage.

Methods inherited from class org.apache.lucene.store.BaseDirectory
ensureOpen, obtainLock, toString

Methods inherited from class org.apache.lucene.store.Directory
copyFrom, getTempFileName, openChecksumInput

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - OUTPUT_AS_MANY_BUFFERS
```
public static final BiFunction<String,ByteBuffersDataOutput,IndexInput> OUTPUT_AS_MANY_BUFFERS
```
  - OUTPUT_AS_ONE_BUFFER
```
public static final BiFunction<String,ByteBuffersDataOutput,IndexInput> OUTPUT_AS_ONE_BUFFER
```
  - OUTPUT_AS_BYTE_ARRAY
```
public static final BiFunction<String,ByteBuffersDataOutput,IndexInput> OUTPUT_AS_BYTE_ARRAY
```
  - OUTPUT_AS_MANY_BUFFERS_LUCENE
```
public static final BiFunction<String,ByteBuffersDataOutput,IndexInput> OUTPUT_AS_MANY_BUFFERS_LUCENE
```
- Constructor Detail
  - ByteBuffersDirectory
```
public ByteBuffersDirectory()
```
  - ByteBuffersDirectory
```
public ByteBuffersDirectory(LockFactory lockFactory)
```
  - ByteBuffersDirectory
```
public ByteBuffersDirectory(LockFactory factory,
                            Supplier<ByteBuffersDataOutput> bbOutputSupplier,
                            BiFunction<String,ByteBuffersDataOutput,IndexInput> outputToInput)
```
- Method Detail
  - listAll
```
public String[] listAll()
                 throws IOException
```
    Description copied from class: Directory
    
    Returns names of all files stored in this directory. The output must be in sorted (UTF-16, java's String.compareTo(java.lang.String)) order.
    
    Specified by:
    
    listAll in class Directory
    
    Throws:
    
    IOException - in case of I/O error
  - deleteFile
```
public void deleteFile(String name)
                throws IOException
```
    Description copied from class: Directory
    
    Removes an existing file in the directory.
    This method must throw either NoSuchFileException or FileNotFoundException if name points to a non-existing file.
    
    Specified by:
    
    deleteFile in class Directory
    
    Parameters:
    
    name - the name of an existing file.
    
    Throws:
    
    IOException - in case of I/O error
  - fileLength
```
public long fileLength(String name)
                throws IOException
```
    Description copied from class: Directory
    
    Returns the byte length of a file in the directory.
    This method must throw either NoSuchFileException or FileNotFoundException if name points to a non-existing file.
    
    Specified by:
    
    fileLength in class Directory
    
    Parameters:
    
    name - the name of an existing file.
    
    Throws:
    
    IOException - in case of I/O error
  - fileExists
```
public boolean fileExists(String name)
```
  - createOutput
```
public IndexOutput createOutput(String name,
                                IOContext context)
                         throws IOException
```
    Description copied from class: Directory
    
    Creates a new, empty file in the directory and returns an IndexOutput instance for appending data to this file.
    This method must throw FileAlreadyExistsException if the file already exists.
    
    Specified by:
    
    createOutput in class Directory
    
    Parameters:
    
    name - the name of the file to create.
    
    Throws:
    
    IOException - in case of I/O error
  - createTempOutput
```
public IndexOutput createTempOutput(String prefix,
                                    String suffix,
                                    IOContext context)
                             throws IOException
```
    Description copied from class: Directory
    
    Creates a new, empty, temporary file in the directory and returns an IndexOutput instance for appending data to this file.
    The temporary file name (accessible via IndexOutput.getName()) will start with prefix, end with suffix and have a reserved file extension .tmp.
    
    Specified by:
    
    createTempOutput in class Directory
    
    Throws:
    
    IOException
  - rename
```
public void rename(String source,
                   String dest)
            throws IOException
```
    Description copied from class: Directory
    
    Renames source file to dest file where dest must not already exist in the directory.
    It is permitted for this operation to not be truly atomic, for example both source and dest can be visible temporarily in Directory.listAll(). However, the implementation of this method must ensure the content of dest appears as the entire source atomically. So once dest is visible for readers, the entire content of previous source is visible.
    This method is used by IndexWriter to publish commits.
    
    Specified by:
    
    rename in class Directory
    
    Throws:
    
    IOException
  - sync
```
public void sync(Collection<String> names)
          throws IOException
```
    Description copied from class: Directory
    
    Ensures that any writes to these files are moved to stable storage (made durable).
    Lucene uses this to properly commit changes to the index, to prevent a machine/OS crash from corrupting the index.
    
    Specified by:
    
    sync in class Directory
    
    Throws:
    
    IOException
    
    See Also:
    
    Directory.syncMetaData()
  - syncMetaData
```
public void syncMetaData()
                  throws IOException
```
    Description copied from class: Directory
    
    Ensures that directory metadata, such as recent file renames, are moved to stable storage.
    
    Specified by:
    
    syncMetaData in class Directory
    
    Throws:
    
    IOException
    
    See Also:
    
    Directory.sync(Collection)
  - openInput
```
public IndexInput openInput(String name,
                            IOContext context)
                     throws IOException
```
    Description copied from class: Directory
    
    Opens a stream for reading an existing file.
    This method must throw either NoSuchFileException or FileNotFoundException if name points to a non-existing file.
    
    Specified by:
    
    openInput in class Directory
    
    Parameters:
    
    name - the name of an existing file.
    
    Throws:
    
    IOException - in case of I/O error
  - close
```
public void close()
           throws IOException
```
    Description copied from class: Directory
    
    Closes the directory.
    
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in interface Closeable
    
    Specified by:
    
    close in class Directory
    
    Throws:
    
    IOException
  - getPendingDeletions
```
public Set<String> getPendingDeletions()
```
    Description copied from class: Directory
    
    Returns a set of files currently pending deletion in this directory.
    
    Specified by:
    
    getPendingDeletions in class Directory

Class ByteBuffersDirectory

Field Summary

Fields inherited from class org.apache.lucene.store.BaseDirectory

Constructor Summary

Method Summary

Methods inherited from class org.apache.lucene.store.BaseDirectory

Methods inherited from class org.apache.lucene.store.Directory

Methods inherited from class java.lang.Object

Field Detail

OUTPUT_AS_MANY_BUFFERS

OUTPUT_AS_ONE_BUFFER

OUTPUT_AS_BYTE_ARRAY

OUTPUT_AS_MANY_BUFFERS_LUCENE

Constructor Detail

ByteBuffersDirectory

ByteBuffersDirectory

ByteBuffersDirectory

Method Detail

listAll

deleteFile

fileLength

fileExists

createOutput

createTempOutput

rename

sync

syncMetaData

openInput

close

getPendingDeletions