com.tangosol.net
Interface Cluster

All Superinterfaces:

ClassLoaderAware, Controllable

public interface Cluster
extends Controllable

The Cluster interface represents a collection of services that operate in a clustered network environment.

Since:

Coherence 1.1

Author:

gg 2002.02.08

Method Summary

Service	ensureService(String sName, String sType) Obtains a Service object for the specified service name and type.
String	getClusterName() Determine the configured name for the Cluster.
Member	getLocalMember() Returns a Member object representing the local (i.e.
Registry	getManagement() Returns the current management registry.
Set	getMemberSet() Returns a Set of Member objects, one for each Member of the cluster.
Member	getOldestMember() Returns a Member object representing the senior cluster member.
Service	getService(String sName) Returns a Service object for the specified service name.
ServiceInfo	getServiceInfo(String sName) Returns a ServiceInfo object for the specified service name.
Enumeration	getServiceNames() Returns an Enumeration of String objects, one for each service that has been previously registered in the cluster.
long	getTimeMillis() Returns the current "cluster time", which is analogous to the System.currentTimeMillis() except that the cluster time is the roughly the same for all Members in the cluster.
void	setManagement(Registry registry) Sets the current management registry.

Methods inherited from interface com.tangosol.util.Controllable

configure, getContextClassLoader, isRunning, setContextClassLoader, shutdown, start, stop

Method Detail

getServiceNames

Enumeration getServiceNames()

Returns an Enumeration of String objects, one for each service that has been previously registered in the cluster.

For each name, a call to getServiceInfo(String) will return a ServiceInfo describing a service. However, the call to getService(String) may return null if that service is not available locally.

Returns:

Enumeration of service names

Throws:

IllegalStateException - thrown if the cluster service is not running or has stopped

getServiceInfo

ServiceInfo getServiceInfo(String sName)

Returns a ServiceInfo object for the specified service name.

Parameters:

sName - the service name, within the cluster, that uniquely identifies a registered service

Returns:

a ServiceInfo for the specified service; null if that service name has not been registered

Throws:

IllegalStateException - thrown if the cluster service is not running or has stopped

See Also:

getService(String)

getService

Service getService(String sName)

Returns a Service object for the specified service name.

Parameters:

sName - the service name, within the cluster, that uniquely identifies a service

Returns:

a Service for the specified name; null if the specified service is not available locally

Throws:

IllegalStateException - thrown if the cluster service is not running or has stopped

See Also:

getServiceInfo(String), ensureService(String, String)

ensureService

Service ensureService(String sName,
                      String sType)

Obtains a Service object for the specified service name and type.

If the service with the specified name already exists, a reference to the same service will be returned. Otherwise a new service object will be instantiated and returned. The service's context ClassLoader will be initialized with the Cluster's context ClassLoader.

It is essential to understand that until the service is started using Controllable.start(), the cluster doesn't keep a reference to that service instance. Therefore, the external synchronization on the cluster object is necessary to prevent creation of a duplicate service.

Parameters:

sName - the service name, within the cluster, that uniquely identifies a service

sType - the service type, that serves as a key to the cluster configuration info, allowing the cluster instantiate the corresponding service implementations if the specified service is not available locally

Returns:

a Service object for the specified service name an type

Throws:

IllegalStateException - thrown if the cluster service is not running or has stopped

IllegalArgumentException - thrown if the type is illegal or unknown

getMemberSet

Set getMemberSet()

Returns a Set of Member objects, one for each Member of the cluster.

Returns:

Set of cluster members

Throws:

IllegalStateException - thrown if the cluster service is not running or has stopped

getLocalMember

Member getLocalMember()

Returns a Member object representing the local (i.e. this JVM) member of the cluster.

Returns:

the local cluster member

Throws:

IllegalStateException - thrown if the cluster service is not running or has stopped

getTimeMillis

long getTimeMillis()

Returns the current "cluster time", which is analogous to the System.currentTimeMillis() except that the cluster time is the roughly the same for all Members in the cluster.

Returns:

the cluster time in milliseconds

Throws:

IllegalStateException - thrown if the cluster service is not running or has stopped

getOldestMember

Member getOldestMember()

Returns a Member object representing the senior cluster member.

Returns:

the senior cluster member

Throws:

IllegalStateException - thrown if the cluster service is not running or has stopped

getManagement

Registry getManagement()

Returns the current management registry.

Returns:

the current management registry or null if the management is disabled on this node

Since:

Coherence 3.0

setManagement

void setManagement(Registry registry)

Sets the current management registry.

Parameters:

registry - the management registry to use on this node

Since:

Coherence 3.0

getClusterName

String getClusterName()

Determine the configured name for the Cluster. This name is defined by the application, and can be used for any application-specific purpose. Furthermore, as a safety feature, when joining into a Cluster, a Member will only join it if the Cluster has the same name as the Member was configured to join.

Returns:

the configured name for the Cluster or null if none is configured

Since:

Coherence 3.2