freenet.store.saltedhash

Class ResizablePersistentIntBuffer

java.lang.Object

freenet.store.saltedhash.ResizablePersistentIntBuffer

public class ResizablePersistentIntBuffer
extends java.lang.Object

A large resizable block of int's, which is persisted to disk with a specific policy, which is either to write it on shutdown, immediately, or every X millis. It would be better to do this with ByteBuffer's and an IntBuffer view, unfortunately it is not possible to subclass ByteBuffer's! Also, ideally we'd memory map, but there is no way to unmap, and it is likely there will never be, so resizing would be very messy and expensive.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_PERSISTENCE_TIME

Constructor Summary

Constructors

Constructor and Description
ResizablePersistentIntBuffer(java.io.File f, int size) Create the buffer.

Method Summary

Modifier and Type	Method and Description
void	abort()
void	fill(int value) Should be called during startup to fill in an appropriate default value e.g.
void	forceWrite()
int	get(int offset)
static int	getPersistenceTime()
boolean	isNew()
void	put(int offset, int value)
void	put(int offset, int value, boolean noWrite)
void	replaceAllEntries(int key, int value)
void	resize(int size)
static void	setPersistenceTime(int val)
void	shutdown()
int	size()
void	start(Ticker ticker)
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_PERSISTENCE_TIME

public static final int DEFAULT_PERSISTENCE_TIME

See Also:

Constant Field Values

Constructor Detail

ResizablePersistentIntBuffer

public ResizablePersistentIntBuffer(java.io.File f,
                                    int size)
                             throws java.io.IOException

Create the buffer. Open the file, creating if necessary, read in the data, and set its size.

Parameters:

f - The filename.

size - The expected size in ints (i.e. multiply by four to get bytes).

Throws:

java.io.IOException

Method Detail

setPersistenceTime

public static void setPersistenceTime(int val)

getPersistenceTime

public static int getPersistenceTime()

fill

public void fill(int value)

Should be called during startup to fill in an appropriate default value e.g. if the store is completely new.

start

public void start(Ticker ticker)

get

public int get(int offset)

put

public void put(int offset,
                int value)
         throws java.io.IOException

Throws:

java.io.IOException

put

public void put(int offset,
                int value,
                boolean noWrite)
         throws java.io.IOException

Throws:

java.io.IOException

shutdown

public void shutdown()

abort

public void abort()

resize

public void resize(int size)

forceWrite

public void forceWrite()

isNew

public boolean isNew()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

replaceAllEntries

public void replaceAllEntries(int key,
                              int value)

size

public int size()