public abstract class FilterDirectory extends Directory
Directory
implementation such as
NRTCachingDirectory
or to add additional
sanity checks for tests. However, if you plan to write your own
Directory
implementation, you should consider extending directly
Directory
or BaseDirectory
rather than try to reuse
functionality of existing Directory
s by extending this class.Modifier | Constructor and Description |
---|---|
protected |
FilterDirectory(Directory in)
Sole constructor, typically called from sub-classes.
|
Modifier and Type | Method and 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.
|
long |
fileLength(String name)
Returns the byte length of a file in the directory.
|
Directory |
getDelegate()
Return the wrapped
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.
|
Lock |
obtainLock(String name)
Acquires and returns a
Lock for a file with the given name. |
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.
|
String |
toString() |
static Directory |
unwrap(Directory dir)
Get the wrapped instance by
dir as long as this reader is
an instance of FilterDirectory . |
copyFrom, ensureOpen, getTempFileName, openChecksumInput
protected final Directory in
protected FilterDirectory(Directory in)
public static Directory unwrap(Directory dir)
dir
as long as this reader is
an instance of FilterDirectory
.public String[] listAll() throws IOException
Directory
String.compareTo(java.lang.String)
) order.listAll
in class Directory
IOException
- in case of I/O errorpublic void deleteFile(String name) throws IOException
Directory
NoSuchFileException
or FileNotFoundException
if name
points to a non-existing file.deleteFile
in class Directory
name
- the name of an existing file.IOException
- in case of I/O errorpublic long fileLength(String name) throws IOException
Directory
NoSuchFileException
or FileNotFoundException
if name
points to a non-existing file.fileLength
in class Directory
name
- the name of an existing file.IOException
- in case of I/O errorpublic IndexOutput createOutput(String name, IOContext context) throws IOException
Directory
IndexOutput
instance for appending data to this file.
This method must throw FileAlreadyExistsException
if the file
already exists.createOutput
in class Directory
name
- the name of the file to create.IOException
- in case of I/O errorpublic IndexOutput createTempOutput(String prefix, String suffix, IOContext context) throws IOException
Directory
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
.createTempOutput
in class Directory
IOException
public void sync(Collection<String> names) throws IOException
Directory
sync
in class Directory
IOException
Directory.syncMetaData()
public void rename(String source, String dest) throws IOException
Directory
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.rename
in class Directory
IOException
public void syncMetaData() throws IOException
Directory
syncMetaData
in class Directory
IOException
Directory.sync(Collection)
public IndexInput openInput(String name, IOContext context) throws IOException
Directory
NoSuchFileException
or FileNotFoundException
if name
points to a non-existing file.openInput
in class Directory
name
- the name of an existing file.IOException
- in case of I/O errorpublic Lock obtainLock(String name) throws IOException
Directory
Lock
for a file with the given name.obtainLock
in class Directory
name
- the name of the lock fileLockObtainFailedException
- (optional specific exception) if the lock could
not be obtained because it is currently held elsewhere.IOException
- if any i/o error occurs attempting to gain the lockpublic void close() throws IOException
Directory
close
in interface Closeable
close
in interface AutoCloseable
close
in class Directory
IOException
public Set<String> getPendingDeletions() throws IOException
Directory
getPendingDeletions
in class Directory
IOException
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