nl.inl.blacklab.contentstore

Class ContentStoreFixedBlockReader

java.lang.Object

nl.inl.blacklab.contentstore.ContentStore

nl.inl.blacklab.contentstore.ContentStoreDirAbstract

nl.inl.blacklab.contentstore.ContentStoreFixedBlock

nl.inl.blacklab.contentstore.ContentStoreFixedBlockReader

@NotThreadSafe
public class ContentStoreFixedBlockReader
extends ContentStoreFixedBlock

Store string content by id in a compound file and a TOC file. Quickly retrieve (parts of) the string content. Stores files in a file containing fixed-length (4K) blocks of zipped UTF-8. A file allocation table keeps track of each file's blocks as well as the character offset associated with each block so we can quickly access the data. Free blocks will be re-used to save space. Thread-safety: not thread-safe in index mode, but thread-safe while searching

Nested Class Summary

Nested classes/interfaces inherited from class nl.inl.blacklab.contentstore.ContentStore

ContentStore.DocTask

Field Summary

Fields inherited from class nl.inl.blacklab.contentstore.ContentStoreFixedBlock

AVERAGE_COMPRESSION_FACTOR, BLOCK_SIZE_BYTES, BYTES_PER_INT, CONSERVATIVE_COMPRESSION_FACTOR, CONTENT_STORE_TYPE_NAME, CONTENTS_FILE_NAME, contentsFile, CURRENT_VERSION, freeBlocks, initialized, MAX_BLOCK_SIZE_BYTES, MAX_COMPRESSION_FACTOR, MINIMUM_ACCEPTABLE_BLOCK_SIZE, nextId, POOL_SIZE, toc, TOC_FILE_NAME, tocFile, tocFileBuffer, tocFileChannel, tocRaf, totalBlocks, TYPICAL_BLOCK_SIZE_CHARACTERS, zipbufPool

Fields inherited from class nl.inl.blacklab.contentstore.ContentStoreDirAbstract

dir

Constructor Summary

Constructors

Constructor and Description
ContentStoreFixedBlockReader(File dir)

Method Summary

Modifier and Type	Method and Description
void	clear() Clear the entire content store.
void	close() Close the content store.
protected String	decodeBlock(byte[] buf, int offset, int length)
void	delete(int id) Delete a document from the content store.
protected void	mapToc(boolean writable)
protected void	performInitialization()
String	retrieve(int id) Retrieve content with given id
String[]	retrieveParts(int contentId, int[] start, int[] end) Retrieve substrings from a document.
int	store(String content) Store a document.
void	storePart(String content) Store part of a large document.

Methods inherited from class nl.inl.blacklab.contentstore.ContentStoreFixedBlock

closeMappedToc, docLength, idSet, initialize, isDeleted, readToc, setStoreType

Methods inherited from class nl.inl.blacklab.contentstore.ContentStoreDirAbstract

getStoreTypeVersion, setStoreType, toString

Methods inherited from class nl.inl.blacklab.contentstore.ContentStore

forEachDocument, open, retrievePart

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ContentStoreFixedBlockReader

public ContentStoreFixedBlockReader(File dir)
                             throws ErrorOpeningIndex

Parameters:

dir - content store dir

Throws:

ErrorOpeningIndex

Method Detail

performInitialization

protected void performInitialization()

Specified by:

performInitialization in class ContentStoreFixedBlock

mapToc

protected void mapToc(boolean writable)
               throws IOException

Specified by:

mapToc in class ContentStoreFixedBlock

Throws:

IOException

close

public void close()

Close the content store.

Overrides:

close in class ContentStoreFixedBlock

retrieve

public String retrieve(int id)

Retrieve content with given id

Specified by:

retrieve in class ContentStore

Parameters:

id - the id

Returns:

the string

retrieveParts

public String[] retrieveParts(int contentId,
                              int[] start,
                              int[] end)

Description copied from class: ContentStore

Retrieve substrings from a document.

Specified by:

retrieveParts in class ContentStore

Parameters:

contentId - content store document id

start - start of the substring

end - end of the substring

Returns:

the substrings

decodeBlock

protected String decodeBlock(byte[] buf,
                             int offset,
                             int length)
                      throws IOException

Throws:

IOException

store

public int store(String content)

Description copied from class: ContentStore

Store a document. It is possible to first call storePart() several times, as long as you finish with a call to store. The parameter may be the empty string if you wish.

Specified by:

store in class ContentStore

Parameters:

content - (part of) the content of the document to store

Returns:

the content store id assigned to the document

storePart

public void storePart(String content)

Description copied from class: ContentStore

Store part of a large document. You can call this several times, but it must end with a call to store() or the document isn't properly stored.

Specified by:

storePart in class ContentStore

Parameters:

content - part of the content of the document to store

clear

public void clear()
           throws IOException

Description copied from class: ContentStore

Clear the entire content store.

Specified by:

clear in class ContentStore

Throws:

IOException

delete

public void delete(int id)

Description copied from class: ContentStore

Delete a document from the content store.

Specified by:

delete in class ContentStore

Parameters:

id - content store id of the document to delete