net.jxta.impl.cm
Class Cm

java.lang.Object
  net.jxta.impl.cm.Cm

All Implemented Interfaces:

Runnable

public final class Cm
extends Object
implements Runnable

This class implements a limited document caching mechanism intended to provide cache for services that have a need for cache to search and exchange jxta documents. Only Core Services are intended to use this mechanism.

ROOTDIRBASE

public static final File ROOTDIRBASE

the name we will use for the base directory

DEFAULT_GC_MAX_INTERVAL

public static final long DEFAULT_GC_MAX_INTERVAL

See Also:

Constant Field Values

rootDir

protected File rootDir

file descriptor for the root of the cm

Cm

public Cm(String areaName,
          boolean enableOptimize)

Constructor for cm

Parameters:

areaName - the name of the cm sub-dir to create

enableOptimize - whether to enable indexing NOTE: Default garbage interval once an hour

Cm

public Cm(ThreadGroup threads,
          String areaName,
          boolean enableOptimize,
          long gcinterval,
          boolean trackDeltas)

Constructor for cm

Parameters:

areaName - the name of the cm sub-dir to create

enableOptimize - whether to enable indexing

gcinterval - garbage collect max interval

trackDeltas - when true deltas are tracked

toString

public String toString()

Overrides:

toString in class Object

createTmpName

public static String createTmpName(StructuredDocument doc)

Generates a random file name using doc hashcode

Parameters:

doc - to hash to generate a unique name

Returns:

String a random file name

getRecords

public Vector getRecords(String dn,
                         int threshold,
                         Vector values,
                         Vector expirations)

Gets the list of all the files into the given folder

Parameters:

dn - contains the name of the folder

Returns:

Vector Strings containing the name of the files

getRecords

public Vector getRecords(String dn,
                         int threshold,
                         Vector values,
                         Vector expirations,
                         boolean purge)

garbageCollect

public void garbageCollect()

getLifetime

public long getLifetime(String dn,
                        String fn)

Returns the relative time in milliseconds at which the file will expire.

Parameters:

dn - contains the name of the folder

fn - contains the name of the file

Returns:

the absolute time in milliseconds at which this document will expire. -1 is returned if the file is not recognized or already expired.

getExpirationtime

public long getExpirationtime(String dn,
                              String fn)

Returns the maximum duration in milliseconds for which this document should cached by those other than the publisher. This value is either the cache lifetime or the remaining lifetime of the document, whichever is less.

Parameters:

dn - contains the name of the folder

fn - contains the name of the file

Returns:

number of milliseconds until the file expires or -1 if the file is not recognized or already expired.

getInputStream

public InputStream getInputStream(String dn,
                                  String fn)
                           throws IOException

Returns the inputStream of a specified file, in a specified dir

Parameters:

dn - directory name

fn - file name

Returns:

The inputStream value

Throws:

IOException - if an I/O error occurs

remove

public void remove(String dn,
                   String fn)
            throws IOException

Remove a file

Parameters:

dn - directory name

fn - file name

Throws:

IOException - if an I/O error occurs

restore

public StructuredDocument restore(String dn,
                                  String fn)
                           throws IOException

Restore a saved StructuredDocument.

Parameters:

dn - directory name

fn - file name

Returns:

StructuredDocument containing the file

Throws:

IOException - if an I/O error occurs was not possible.

restoreBytes

public byte[] restoreBytes(String dn,
                           String fn)
                    throws IOException

Restore an advetisement into a byte array.

Parameters:

dn - directory name

fn - file name

Returns:

byte [] containing the file

Throws:

IOException - if an I/O error occurs

save

public void save(String dn,
                 String fn,
                 Advertisement adv)
          throws IOException

Stores a StructuredDocument in specified dir, and file name

Parameters:

dn - directory name

fn - file name

adv - Advertisement to store

Throws:

IOException - if an I/O error occurs

save

public void save(String dn,
                 String fn,
                 Advertisement adv,
                 long lifetime,
                 long expiration)
          throws IOException

Stores a StructuredDocument in specified dir, and file name, and associated doc timeouts

Parameters:

dn - directory name

fn - file name

adv - Advertisement to save

expiration - document expiration time in ms

lifetime - document lifetime in ms

Throws:

IOException - if an I/O error occurs

save

public void save(String dn,
                 String fn,
                 byte[] data,
                 long lifetime,
                 long expiration)
          throws IOException

Store some bytes in specified dir, and file name, and associated doc timeouts

Parameters:

dn - directory name

fn - file name

data - byte array to save

expiration - document expiration time in ms

lifetime - document lifetime in ms

Throws:

IOException - if an I/O error occurs

getIndexQuery

protected static IndexQuery getIndexQuery(String value)

search

public Vector search(String dn,
                     String attribute,
                     String value,
                     int threshold,
                     Vector expirations)

Search and recovers documents that contains at least a macthing pair of tag/value.

Parameters:

dn - contains the name of the folder on which to perform the search

value - contains the value to search on.

attribute - attribute to search on

threshold - threshold

Returns:

Enumeration containing of all the documents names

getEntries

public Vector getEntries(String dn,
                         boolean clearDeltas)

returns all entries that are cached

Parameters:

dn - the relative dir name

Returns:

SrdiMessage.Entries

getDeltas

public Vector getDeltas(String dn)

returns all entries that are added since this method was last called

Parameters:

dn - the relative dir name

Returns:

SrdiMessage.Entries

setTrackDeltas

public void setTrackDeltas(boolean trackDeltas)

stop

public void stop()

stop the cm

run

public void run()

Specified by:

run in interface Runnable