org.cometd.bayeux

Class ChannelId

java.lang.Object

org.cometd.bayeux.ChannelId

public class ChannelId
extends Object

Reification of a channel id with methods to test properties and compare with other ChannelIds.

A ChannelId breaks the channel id into path segments so that, for example, /foo/bar breaks into ["foo","bar"].

ChannelId can be wild, when they end with one or two wild characters "*"; a ChannelId is shallow wild if it ends with one wild character (for example /foo/bar/*) and deep wild if it ends with two wild characters (for example /foo/bar/**).

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEEPWILD
static String	WILD

Constructor Summary

Constructors

Constructor and Description
ChannelId(String id) Constructs a new ChannelId with the given id

Method Summary

Methods

Modifier and Type	Method and Description
int	depth()
boolean	equals(Object obj)
String	getParent()
String	getSegment(int i)
List<String>	getWilds()
int	hashCode()
boolean	isAncestorOf(ChannelId id)
boolean	isBroadcast()
static boolean	isBroadcast(String channelId) Helper method to test if the string form of a ChannelId represents a isBroadcast() broadcast} ChannelId.
boolean	isDeepWild() Deep wild ChannelIds end with a double wild character "**" and match non wild channels with the same or greater depth.
boolean	isMeta() A ChannelId is a meta ChannelId if it starts with "/meta/".
static boolean	isMeta(String channelId) Helper method to test if the string form of a ChannelId represents a meta ChannelId.
boolean	isParentOf(ChannelId id)
boolean	isService() A ChannelId is a service ChannelId if it starts with "/service/".
static boolean	isService(String channelId) Helper method to test if the string form of a ChannelId represents a isService() service} ChannelId.
boolean	isShallowWild() Shallow wild ChannelIds end with a single wild character "*" and match non wild channels with the same depth.
boolean	isWild()
boolean	matches(ChannelId channelId) Tests whether this ChannelId matches the given ChannelId.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

WILD

public static final String WILD

See Also:

Constant Field Values

DEEPWILD

public static final String DEEPWILD

See Also:

Constant Field Values

Constructor Detail

ChannelId

public ChannelId(String id)

Constructs a new ChannelId with the given id

Parameters:

id - the channel id in string form

Method Detail

isWild

public boolean isWild()

Returns:

whether this ChannelId is either shallow wild or deep wild

isShallowWild

public boolean isShallowWild()

Shallow wild ChannelIds end with a single wild character "*" and match non wild channels with the same depth.

Example: /foo/* matches /foo/bar, but not /foo/bar/baz.

Returns:

whether this ChannelId is a shallow wild channel id

isDeepWild

public boolean isDeepWild()

Deep wild ChannelIds end with a double wild character "**" and match non wild channels with the same or greater depth.

Example: /foo/** matches /foo/bar and /foo/bar/baz.

Returns:

whether this ChannelId is a deep wild channel id

isMeta

public boolean isMeta()

A ChannelId is a meta ChannelId if it starts with "/meta/".

Returns:

whether the first segment is "meta"

isService

public boolean isService()

A ChannelId is a service ChannelId if it starts with "/service/".

Returns:

whether the first segment is "service"

isBroadcast

public boolean isBroadcast()

Returns:

whether this ChannelId is neither meta nor service

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

matches

public boolean matches(ChannelId channelId)

Tests whether this ChannelId matches the given ChannelId.

If the given ChannelId is wild, then it matches only if it is equal to this ChannelId.

If this ChannelId is non-wild, then it matches only if it is equal to the given ChannelId.

Otherwise, this ChannelId is either shallow or deep wild, and matches ChannelIds with the same number of equal segments (if it is shallow wild), or ChannelIds with the same or a greater number of equal segments (if it is deep wild).

Parameters:

channelId - the channelId to match

Returns:

true if this ChannelId matches the given ChannelId

toString

public String toString()

Overrides:

toString in class Object

depth

public int depth()

Returns:

how many segments this ChannelId is made of

See Also:

getSegment(int)

isAncestorOf

public boolean isAncestorOf(ChannelId id)

Parameters:

id - the channel to test

Returns:

whether this ChannelId is an ancestor of the given ChannelId

See Also:

isParentOf(ChannelId)

isParentOf

public boolean isParentOf(ChannelId id)

Parameters:

id - the channel to test

Returns:

whether this ChannelId is the parent of the given ChannelId

See Also:

isAncestorOf(ChannelId)

getParent

public String getParent()

Returns:

the ChannelId parent of this ChannelId

See Also:

isParentOf(ChannelId)

getSegment

public String getSegment(int i)

Parameters:

i - the segment index

Returns:

the i-nth segment of this channel, or null if no such segment exist

See Also:

depth()

getWilds

public List<String> getWilds()

Returns:

The list of wilds channels that match this channel, or the empty list if this channel is already wild.

isMeta

public static boolean isMeta(String channelId)

Helper method to test if the string form of a ChannelId represents a meta ChannelId.

Parameters:

channelId - the channel id to test

Returns:

whether the given channel id is a meta channel id

isService

public static boolean isService(String channelId)

Helper method to test if the string form of a ChannelId represents a isService() service} ChannelId.

Parameters:

channelId - the channel id to test

Returns:

whether the given channel id is a service channel id

isBroadcast

public static boolean isBroadcast(String channelId)

Helper method to test if the string form of a ChannelId represents a isBroadcast() broadcast} ChannelId.

Parameters:

channelId - the channel id to test

Returns:

whether the given channel id is a broadcast channel id