Class FilterDirectory
- All Implemented Interfaces:
Closeable,AutoCloseable
- Direct Known Subclasses:
LockValidatingDirectoryWrapper,NRTCachingDirectory,SleepingLockWrapper,TrackingDirectoryWrapper
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 Directorys by extending this class.- NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.
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Field Summary
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Constructor Summary
ConstructorsModifierConstructorDescriptionprotectedSole constructor, typically called from sub-classes. -
Method Summary
Modifier and TypeMethodDescriptionvoidclose()Closes the directory.createOutput(String name, IOContext context) Creates a new, empty file in the directory and returns anIndexOutputinstance for appending data to this file.createTempOutput(String prefix, String suffix, IOContext context) Creates a new, empty, temporary file in the directory and returns anIndexOutputinstance for appending data to this file.voiddeleteFile(String name) Removes an existing file in the directory.protected voidEnsures this directory is still open.longfileLength(String name) Returns the byte length of a file in the directory.final DirectoryReturn the wrappedDirectory.Returns a set of files currently pending deletion in this directory.String[]listAll()Returns names of all files stored in this directory.obtainLock(String name) Acquires and returns aLockfor a file with the given name.Opens a stream for reading an existing file.voidRenamessourcefile todestfile wheredestmust not already exist in the directory.voidsync(Collection<String> names) Ensures that any writes to these files are moved to stable storage (made durable).voidEnsures that directory metadata, such as recent file renames, are moved to stable storage.toString()static DirectoryGet the wrapped instance bydiras long as this reader is an instance ofFilterDirectory.Methods inherited from class org.apache.lucene.store.Directory
copyFrom, getTempFileName, openChecksumInput
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Field Details
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in
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Constructor Details
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FilterDirectory
Sole constructor, typically called from sub-classes.
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Method Details
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unwrap
Get the wrapped instance bydiras long as this reader is an instance ofFilterDirectory. -
getDelegate
Return the wrappedDirectory. -
listAll
Description copied from class:DirectoryReturns names of all files stored in this directory. The output must be in sorted (UTF-16, java'sString.compareTo(java.lang.String)) order.- Specified by:
listAllin classDirectory- Throws:
IOException- in case of I/O error
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deleteFile
Description copied from class:DirectoryRemoves an existing file in the directory.This method must throw either
NoSuchFileExceptionorFileNotFoundExceptionifnamepoints to a non-existing file.- Specified by:
deleteFilein classDirectory- Parameters:
name- the name of an existing file.- Throws:
IOException- in case of I/O error
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fileLength
Description copied from class:DirectoryReturns the byte length of a file in the directory.This method must throw either
NoSuchFileExceptionorFileNotFoundExceptionifnamepoints to a non-existing file.- Specified by:
fileLengthin classDirectory- Parameters:
name- the name of an existing file.- Throws:
IOException- in case of I/O error
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createOutput
Description copied from class:DirectoryCreates a new, empty file in the directory and returns anIndexOutputinstance for appending data to this file.This method must throw
FileAlreadyExistsExceptionif the file already exists.- Specified by:
createOutputin classDirectory- Parameters:
name- the name of the file to create.- Throws:
IOException- in case of I/O error
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createTempOutput
public IndexOutput createTempOutput(String prefix, String suffix, IOContext context) throws IOException Description copied from class:DirectoryCreates a new, empty, temporary file in the directory and returns anIndexOutputinstance for appending data to this file.The temporary file name (accessible via
IndexOutput.getName()) will start withprefix, end withsuffixand have a reserved file extension.tmp.- Specified by:
createTempOutputin classDirectory- Throws:
IOException
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sync
Description copied from class:DirectoryEnsures 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:
syncin classDirectory- Throws:
IOException- See Also:
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rename
Description copied from class:DirectoryRenamessourcefile todestfile wheredestmust not already exist in the directory.It is permitted for this operation to not be truly atomic, for example both
sourceanddestcan be visible temporarily inDirectory.listAll(). However, the implementation of this method must ensure the content ofdestappears as the entiresourceatomically. So oncedestis visible for readers, the entire content of previoussourceis visible.This method is used by IndexWriter to publish commits.
- Specified by:
renamein classDirectory- Throws:
IOException
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syncMetaData
Description copied from class:DirectoryEnsures that directory metadata, such as recent file renames, are moved to stable storage.- Specified by:
syncMetaDatain classDirectory- Throws:
IOException- See Also:
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openInput
Description copied from class:DirectoryOpens a stream for reading an existing file.This method must throw either
NoSuchFileExceptionorFileNotFoundExceptionifnamepoints to a non-existing file.- Specified by:
openInputin classDirectory- Parameters:
name- the name of an existing file.- Throws:
IOException- in case of I/O error
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obtainLock
Description copied from class:DirectoryAcquires and returns aLockfor a file with the given name.- Specified by:
obtainLockin classDirectory- Parameters:
name- the name of the lock file- Throws:
IOException- if any i/o error occurs attempting to gain the lock
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close
Description copied from class:DirectoryCloses the directory.- Specified by:
closein interfaceAutoCloseable- Specified by:
closein interfaceCloseable- Specified by:
closein classDirectory- Throws:
IOException
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toString
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getPendingDeletions
Description copied from class:DirectoryReturns a set of files currently pending deletion in this directory.- Specified by:
getPendingDeletionsin classDirectory- Throws:
IOException
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ensureOpen
Description copied from class:DirectoryEnsures this directory is still open.- Overrides:
ensureOpenin classDirectory- Throws:
AlreadyClosedException- if this directory is closed.
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