Package io.hekate.cluster.seed

Class SeedNodeProviderGroup

java.lang.Object

io.hekate.cluster.seed.SeedNodeProviderGroup

All Implemented Interfaces:

SeedNodeProvider, JmxSupport<Collection<? extends SeedNodeProvider>>, ConfigReportSupport

public class SeedNodeProviderGroup
extends Object
implements SeedNodeProvider, JmxSupport<Collection<? extends SeedNodeProvider>>, ConfigReportSupport

Group of SeedNodeProviders.

This class provides support for registering multiple SeedNodeProviders simultaneously to the ClusterService and act as a single provider.

It is possible to specify an error handling policy via the SeedNodeProviderGroupConfig.setPolicy(SeedNodeProviderGroupPolicy) method. For the list of available policies please see the documentation of SeedNodeProviderGroupPolicy enum's values.

Below is the configuration example:

// Prepare seed node providers group.
SeedNodeProviderGroupConfig seedGroupCfg = new SeedNodeProviderGroupConfig()
    // First provider.
    .withProvider(
        new MulticastSeedNodeProvider(
            new MulticastSeedNodeProviderConfig()
                .withGroup("224.1.2.12")
                .withPort(45454)
                .withInterval(200)
                .withWaitTime(1000)
        )
    )
    // Second provider.
    .withProvider(
        new FsSeedNodeProvider(
            new FsSeedNodeProviderConfig().withWorkDir(tempDir)
        )
    )
    // Do not fail if at least one provider can find seed nodes.
    .withPolicy(SeedNodeProviderGroupPolicy.IGNORE_PARTIAL_ERRORS);

// Start node.
Hekate hekate = new HekateBootstrap()
    .withCluster(cluster -> {
        // Register the providers group to the cluster service.
        cluster.withSeedNodeProvider(new SeedNodeProviderGroup(seedGroupCfg));
    })
    .join();

See Also:

SeedNodeProviderGroupPolicy, SeedNodeProviderGroupConfig

Constructor Summary

Constructors

Constructor	Description
SeedNodeProviderGroup(SeedNodeProviderGroupConfig cfg)	Constructs a new instance.

Method Summary

Modifier and Type	Method	Description
List<SeedNodeProvider>	allProviders()	Returns an immutable list of all providers that are configured for this group.
long	cleanupInterval()	Returns the time interval in milliseconds for the cluster service to perform the stale data cleaning.
<T> Optional<T>	findProvider(Class<T> type)	Searches for a seed node provider of the specified type.
List<InetSocketAddress>	findSeedNodes(String namespace)	Returns the list of known seed node addresses.
Collection<? extends SeedNodeProvider>	jmx()	Creates a JMX object.
List<SeedNodeProvider>	liveProviders()	Returns a copy of a list of all providers that were successfully started.
SeedNodeProviderGroupPolicy	policy()	Returns the error handling policy of this group.
void	registerRemote(String namespace, InetSocketAddress node)	Registered the specified addresses within this provider.
void	report(ConfigReporter report)	Report configuration.
void	startDiscovery(String namespace, InetSocketAddress node)	Registers the local node address and starts this provider.
void	stopDiscovery(String namespace, InetSocketAddress node)	Unregisters the local node address and stops this provider.
void	suspendDiscovery()	Suspends discovery activities.
String	toString()
void	unregisterRemote(String namespace, InetSocketAddress node)	Unregisters the specified address from this provider.

Methods inherited from class java.lang.Object

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

Constructor Detail

SeedNodeProviderGroup

public SeedNodeProviderGroup(SeedNodeProviderGroupConfig cfg)

Constructs a new instance.

Parameters:

cfg - Configuration.

Method Detail

report

public void report(ConfigReporter report)

Description copied from interface: ConfigReportSupport

Report configuration.

Specified by:

report in interface ConfigReportSupport

Parameters:

report - Reporter.

allProviders

public List<SeedNodeProvider> allProviders()

Returns an immutable list of all providers that are configured for this group.

Returns:

Immutable list of all providers of this group.

See Also:

SeedNodeProviderGroupConfig.setProviders(List)

liveProviders

public List<SeedNodeProvider> liveProviders()

Returns a copy of a list of all providers that were successfully started.

Returns:

Copy of a list of all providers that were successfully started.

See Also:

SeedNodeProvider.startDiscovery(String, InetSocketAddress)

findProvider

public <T> Optional<T> findProvider(Class<T> type)

Searches for a seed node provider of the specified type.

Type Parameters:

T - Type of a seed node provider.

Parameters:

type - Type of a seed node provider.

Returns:

Seed node provider.

policy

public SeedNodeProviderGroupPolicy policy()

Returns the error handling policy of this group.

Returns:

Error handling policy of this group.

See Also:

SeedNodeProviderGroupConfig.setPolicy(SeedNodeProviderGroupPolicy)

cleanupInterval

public long cleanupInterval()

Description copied from interface: SeedNodeProvider

Returns the time interval in milliseconds for the cluster service to perform the stale data cleaning. If the returned value if less than or equals to zero then stale data cleaning will be disabled.

Specified by:

cleanupInterval in interface SeedNodeProvider

Returns:

Time interval in milliseconds.

findSeedNodes

public List<InetSocketAddress> findSeedNodes(String namespace)
                                      throws HekateException

Description copied from interface: SeedNodeProvider

Returns the list of known seed node addresses.

Specified by:

findSeedNodes in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

Returns:

List of known seed node addresses.

Throws:

HekateException - if failed to provide seed node addresses information due to the system failure.

startDiscovery

public void startDiscovery(String namespace,
                           InetSocketAddress node)
                    throws HekateException

Description copied from interface: SeedNodeProvider

Registers the local node address and starts this provider.

Specified by:

startDiscovery in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

node - Local node address.

Throws:

HekateException - If failed to start discovery due to the system failure.

suspendDiscovery

public void suspendDiscovery()
                      throws HekateException

Description copied from interface: SeedNodeProvider

Suspends discovery activities.

Specified by:

suspendDiscovery in interface SeedNodeProvider

Throws:

HekateException - If failed to suspend discovery activities due to some system failure.

stopDiscovery

public void stopDiscovery(String namespace,
                          InetSocketAddress node)
                   throws HekateException

Description copied from interface: SeedNodeProvider

Unregisters the local node address and stops this provider.

Specified by:

stopDiscovery in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

node - Local node address.

Throws:

HekateException - If failed to stop discovery due to the system failure.

registerRemote

public void registerRemote(String namespace,
                           InetSocketAddress node)
                    throws HekateException

Description copied from interface: SeedNodeProvider

Registered the specified addresses within this provider.

This method is the part of a stale data cleanup activity and is performed by the cluster service if it detects that particular node is within its cluster topology but is not registered within this provider (i.e. not returned from SeedNodeProvider.findSeedNodes(String) method).

Specified by:

registerRemote in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

node - Node address that should be registered.

Throws:

HekateException - If node couldn't be registered due to the system failure.

unregisterRemote

public void unregisterRemote(String namespace,
                             InetSocketAddress node)
                      throws HekateException

Description copied from interface: SeedNodeProvider

Unregisters the specified address from this provider.

This method is the part of a stale data cleanup activity and is called by the cluster service if it detects that there is no cluster node running at the specified address while this address is still registered within this provider (i.e. is returned from SeedNodeProvider.findSeedNodes(String) method).

Specified by:

unregisterRemote in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

node - Node address that should be unregistered.

Throws:

HekateException - If node couldn't be unregistered due to the system failure.

jmx

public Collection<? extends SeedNodeProvider> jmx()

Description copied from interface: JmxSupport

Creates a JMX object.

Specified by:

jmx in interface JmxSupport<Collection<? extends SeedNodeProvider>>

Returns:

JMX object.

toString

public String toString()

Overrides:

toString in class Object