com.monitorjbl.xlsx.sst

Class FileBackedList

java.lang.Object

com.monitorjbl.xlsx.sst.FileBackedList

All Implemented Interfaces:

AutoCloseable

public class FileBackedList
extends Object
implements AutoCloseable

File-backed list-like class. Allows addition of arbitrary numbers of array entries (serialized to JSON) in a binary packed file. Reading of entries is done with an NIO channel that seeks to the entry in the file.

File entry format:

• 4 bytes: length of entry
• length bytes: JSON string containing the entry data

Pointers to the offset of each entry are kept in a List<Long>. The values loaded from the the file are cached up to a maximum of cacheSize. Items are evicted from the cache with an LRU algorithm.

Constructor Summary

Constructors

Constructor and Description
FileBackedList(File file, int cacheSize)

Method Summary

Modifier and Type	Method and Description
void	add(String str)
void	close()
String	getAt(int index)

Methods inherited from class java.lang.Object

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

Constructor Detail

FileBackedList

public FileBackedList(File file,
                      int cacheSize)
               throws IOException

Throws:

IOException

Method Detail

add

public void add(String str)

getAt

public String getAt(int index)

close

public void close()

Specified by:

close in interface AutoCloseable