org.ceryle.xnode
Class XNodeStoreChangeCache

java.lang.Object
  org.ceryle.xnode.XNodeStoreChangeCache

public class XNodeStoreChangeCache
extends Object

Backed by a Stack, acts as a list of XNodeStoreEvents received by an XNodeStoreListener attached to the XNodeStore. Note that upon creation of an XNodeStoreChangeCache object, it will automatically attach a listener to the XNodeStore (which is a singleton class in this implementation). It's possible to create multiple caches (for whatever reason); each will add its own listener. To remove a cache, it's first necessary to call its removeListener() method to remove the listener, otherwise it will remain, hanging.

The cache can be directly manipulated as a Stack.

There is some code to support separate indexing on a per-Collection basis, but given that indexes are currently for the entire database, it's not used.

Since:

XNode 1.1

Version:

$Id: XNodeStoreChangeCache.java,v 3.9 2007-06-15 12:10:31 altheim Exp $

Author:

Murray Altheim

Field Summary

static int	COL_ADD The int code indicating a new Collection has been added.
static int	COL_DEL The int code indicating a Collection has been deleted.
static int	COL_MOD The int code indicating a Collection has been modified (by adding, modifying or deleting nodes).
static int	NODE_ADD The int code indicating a new Node has been added.
static int	NODE_DEL The int code indicating a Node has been deleted.
static int	NODE_MOD The int code indicating a Node has been modified.
static int	REINDEX The int code indicating that the number of changes that have occurred has passed the threshold for rebuilding the entire database index.

Constructor Summary

XNodeStoreChangeCache(XNodeStore xnodestore)
Default constructor with an XNodeStore.

Method Summary

protected void	addDefaultListener() Adds the listener that this XNodeStoreChangeCache uses to create the cache of event notifications to the XNodeStore.
void	clear() Clear the cache contents.
Stack	getCache() Return the cache contents as a Stack.
static String[]	parseEntry(String entry) Provided a space-delimited cache entry, returns a three element array containing its fields in entry order: type, cid, nid.
void	removeListener() Removes this XNodeStoreChangeCache's listener from the XNodeStore.
String	tostring() Returns the cache as a string (nl-delimited list of type+cid).

Methods inherited from class java.lang.Object

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

Field Detail

REINDEX

public static final int REINDEX

The int code indicating that the number of changes that have occurred has passed the threshold for rebuilding the entire database index.

See Also:

Constant Field Values

COL_ADD

public static final int COL_ADD

The int code indicating a new Collection has been added.

See Also:

Constant Field Values

COL_DEL

public static final int COL_DEL

The int code indicating a Collection has been deleted.

See Also:

Constant Field Values

COL_MOD

public static final int COL_MOD

The int code indicating a Collection has been modified (by adding, modifying or deleting nodes).

See Also:

Constant Field Values

NODE_ADD

public static final int NODE_ADD

The int code indicating a new Node has been added.

See Also:

Constant Field Values

NODE_DEL

public static final int NODE_DEL

The int code indicating a Node has been deleted.

See Also:

Constant Field Values

NODE_MOD

public static final int NODE_MOD

The int code indicating a Node has been modified.

See Also:

Constant Field Values

Constructor Detail

XNodeStoreChangeCache

public XNodeStoreChangeCache(XNodeStore xnodestore)
                      throws XNodeException

Default constructor with an XNodeStore.

Throws:

XNodeException - if unable to add the cache listener to the XNodeStore.

Method Detail

addDefaultListener

protected void addDefaultListener()

Adds the listener that this XNodeStoreChangeCache uses to create the cache of event notifications to the XNodeStore.

removeListener

public void removeListener()

Removes this XNodeStoreChangeCache's listener from the XNodeStore.

parseEntry

public static String[] parseEntry(String entry)

Provided a space-delimited cache entry, returns a three element array containing its fields in entry order: type, cid, nid. The last element (the node ID) may be null, for those events that did not involve capturing it.

clear

public void clear()

Clear the cache contents.

getCache

public Stack getCache()

Return the cache contents as a Stack.

tostring

public String tostring()

Returns the cache as a string (nl-delimited list of type+cid).