com.sun.enterprise.ee.cms.core
Enum ServiceProviderConfigurationKeys

java.lang.Object
  java.lang.Enum<ServiceProviderConfigurationKeys>
      com.sun.enterprise.ee.cms.core.ServiceProviderConfigurationKeys

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<ServiceProviderConfigurationKeys>

public enum ServiceProviderConfigurationKeys
extends java.lang.Enum<ServiceProviderConfigurationKeys>

Provides the keys that correspond to properties within group communication providers that can be configured. Note that this is not exhaustive enough to cover all possible configurations in different group communication libraries.

Author:

Shreedhar Ganapathy

Enum Constant Summary

BIND_INTERFACE_ADDRESS
If you wish to specify a particular network interface that should be used for all group communication messages, use this key and specify an interface address.

DISCOVERY_TIMEOUT
The timeout in milliseconds that each member would wait to discover a group leader.

DISCOVERY_URI_LIST
Enables a starting GMS member to discover and join its group without requiring UDP multicast.

FAILURE_DETECTION_RETRIES
Number of periodic heartbeats than can be missed in order to be determined a suspected failure.

FAILURE_DETECTION_TCP_RETRANSMIT_PORT
This value of this key is a port common to all cluster members where a socket will be attempted to be created when a particular instance's configured periodic heartbeats have been missed for the max retry times.

FAILURE_DETECTION_TCP_RETRANSMIT_TIMEOUT
Maximum time that the health monitoring protocol would wait for a reachability query to block for a response.

FAILURE_DETECTION_TIMEOUT
The timeout in milliseconds which will be used to send out periodic heartbeats.

FAILURE_VERIFICATION_TIMEOUT
The timeout in milliseconds which will be used to wait and verify that the suspected member has indeed failed.

INCOMING_MESSAGE_QUEUE_SIZE
Enable setting how large fixed incoming message queue is.

INCOMING_MESSAGE_THREAD_POOL_SIZE
Configure number of threads for incoming message processing.

IS_BOOTSTRAPPING_NODE
Represents a key whose value is set to true if this node will be a bootstrapping host for other members to use for discovery purposes.

LOOPBACK
Setting the value of this key to true, would make all application level messages sent by this member to also be received by this member in addition to the target members to whom the message was sent.

MAX_MESSAGE_LENGTH
Max message length.

MONITORING
Set MONITORING frequency in seconds.

MULTICAST_POOLSIZE
OPTIONAL: not a meaningful option for all implementations.

MULTICASTADDRESS
unreserved valid multicast address in the range 224.0.0.0 through 239.255.255.255 See http://www.iana.org/assignments/multicast-addresses for more details on valid addresses.

MULTICASTPORT
A valid port.

VIRTUAL_MULTICAST_URI_LIST
This enum represents a key the value of which is a comma separated list of initial bootstrapping tcp addresses.

Method Summary

static ServiceProviderConfigurationKeys	valueOf(java.lang.String name) Returns the enum constant of this type with the specified name.
static ServiceProviderConfigurationKeys[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

MULTICASTADDRESS

public static final ServiceProviderConfigurationKeys MULTICASTADDRESS

unreserved valid multicast address in the range 224.0.0.0 through 239.255.255.255 See http://www.iana.org/assignments/multicast-addresses for more details on valid addresses. If not using multicast, do not specify this property

MULTICASTPORT

public static final ServiceProviderConfigurationKeys MULTICASTPORT

A valid port. If not using multicast, do not specify this property

FAILURE_DETECTION_TIMEOUT

public static final ServiceProviderConfigurationKeys FAILURE_DETECTION_TIMEOUT

The timeout in milliseconds which will be used to send out periodic heartbeats. This is also the period that will be used to check for update to the health state of each member process.

FAILURE_DETECTION_RETRIES

public static final ServiceProviderConfigurationKeys FAILURE_DETECTION_RETRIES

Number of periodic heartbeats than can be missed in order to be determined a suspected failure. Once the retries have been exhausted, a FailureSuspectedNotificationSignal is sent out to all GMS clients who have registered for this event.

FAILURE_VERIFICATION_TIMEOUT

public static final ServiceProviderConfigurationKeys FAILURE_VERIFICATION_TIMEOUT

The timeout in milliseconds which will be used to wait and verify that the suspected member has indeed failed. Once confirmed failed, a FailureNotificationSignal is sent out to all GMS clients who have registered for this event.

DISCOVERY_TIMEOUT

public static final ServiceProviderConfigurationKeys DISCOVERY_TIMEOUT

The timeout in milliseconds that each member would wait to discover a group leader. If no group leader was found within this timeout, the member announces itself as the assumed and assigned group leader.

LOOPBACK

public static final ServiceProviderConfigurationKeys LOOPBACK

Setting the value of this key to true, would make all application level messages sent by this member to also be received by this member in addition to the target members to whom the message was sent.

IS_BOOTSTRAPPING_NODE

public static final ServiceProviderConfigurationKeys IS_BOOTSTRAPPING_NODE

Represents a key whose value is set to true if this node will be a bootstrapping host for other members to use for discovery purposes. This is particularly useful when multicast traffic is not supported in the network or cluster members are located outside a multicast supported network area. Setting the value of this to true requires specifying a URI corresponding to this member process's IP address and port with tcp protocol, as a value in the VIRTUAL_MULTICAST_URI_LIST property. See below for the VIRTUAL_MULTICAST_URI_LIST property

VIRTUAL_MULTICAST_URI_LIST

public static final ServiceProviderConfigurationKeys VIRTUAL_MULTICAST_URI_LIST

This enum represents a key the value of which is a comma separated list of initial bootstrapping tcp addresses. This address list must be specified on all members of the cluster through this property.

Typically an address uri would be specified as tcp://ipaddress:port

The port here could be any available unoccupied port.
Specifying this list is helpful particularly when cluster members are located beyond one subnet or multicast traffic is disabled. Deprecated and used only by Shoal GMS over JXTA transport.

DISCOVERY_URI_LIST

public static final ServiceProviderConfigurationKeys DISCOVERY_URI_LIST

Enables a starting GMS member to discover and join its group without requiring UDP multicast. This enum represents a key with value that is a comma separated list of initial bootstrapping uri addresses. There must be a GMS member running at one of these bootstrapping addresses to enable the current member to join the group. This list must be specified on all members of the cluster through this property.

The bootstrap address uri is specified as protocol://ipaddress:port. The protocol and/or the port are optional. Their values will be defaulted when they are left out. Thus, allowing the list to be a comma separated list of ip addresses or of protcol://ipaddress. An example address uri is tcp://someDnsHostName:port or tcp://ipAddress:port.

The default port is the GMS property TCPSTARTPORT. * When the scheme is ommitted, the default scheme is tcp. Initial implementation will only support tcp.

If this value is set to an empty list, it indicates that this is the first instance starting in the cluster. Setting this value to empty string indicates that UDP multicast is disabled.

When the list is not empty, at least one of the instances refernenced by the uri must be able to be contacted to enable joining an active GMS group.

TODO: multi-home machine considerations. On multi-home machines, it is quite probable that one will be required to set GMS property BIND_INTERFACE_ADDRESS. It is network stack specific which network interface address is selected when there are multiple enabled network interfaces.

BIND_INTERFACE_ADDRESS

public static final ServiceProviderConfigurationKeys BIND_INTERFACE_ADDRESS

If you wish to specify a particular network interface that should be used for all group communication messages, use this key and specify an interface address. This is the address which Shoal would pass down to a service provider such as Jxta to bind to for communication.

FAILURE_DETECTION_TCP_RETRANSMIT_TIMEOUT

public static final ServiceProviderConfigurationKeys FAILURE_DETECTION_TCP_RETRANSMIT_TIMEOUT

Maximum time that the health monitoring protocol would wait for a reachability query to block for a response. After this time expires, the health monitoring protocol would report a failure based on the fact that an endpoint was unreachable for this length of time.
Specifying this property is typically helpful in determining hardware and network failures within a shorter time period than the OS/System configured TCP retransmission timeout. On many OSs, the TCP retransmission timeout is about 10 minutes.

The default timeout for this property is set to 30 seconds.

As an example, let's take the case of 2 machines A and B hosting instances X and Y, respectively. Machine B goes down due to a power outage or a hardware failure.

Under normal circumstances, Instance X on machine A would not know of the unavailability of Instance X on Machine B until the TCP retransmission timeout (typically 10 minutes) has passed. By setting this property's value to some lower time threshold, instance X would determine Y's failure due to Machine B's failure, a lot earlier.

Related to this key is the FAILURE_DETECTION_TCP_RETRANSMIT_PORT. See below

FAILURE_DETECTION_TCP_RETRANSMIT_PORT

public static final ServiceProviderConfigurationKeys FAILURE_DETECTION_TCP_RETRANSMIT_PORT

This value of this key is a port common to all cluster members where a socket will be attempted to be created when a particular instance's configured periodic heartbeats have been missed for the max retry times. The port number specified should be an available unoccupied port on all machines involved in the cluster. If the socket creation attempt blocks for the above-mentioned FAILURE_DETECTION_TCP_RETRANSMIT_TIMEOUT, then the health monitoring protocol would return a failure event.

MULTICAST_POOLSIZE

public static final ServiceProviderConfigurationKeys MULTICAST_POOLSIZE

OPTIONAL: not a meaningful option for all implementations. Specify the max number of threads allocated to run handlers for incoming multicast messages.

INCOMING_MESSAGE_QUEUE_SIZE

public static final ServiceProviderConfigurationKeys INCOMING_MESSAGE_QUEUE_SIZE

Enable setting how large fixed incoming message queue is.

MAX_MESSAGE_LENGTH

public static final ServiceProviderConfigurationKeys MAX_MESSAGE_LENGTH

Max message length. This length is not just application payload but includes message overhead (such as headers) that is implementation and transport dependent.

INCOMING_MESSAGE_THREAD_POOL_SIZE

public static final ServiceProviderConfigurationKeys INCOMING_MESSAGE_THREAD_POOL_SIZE

Configure number of threads for incoming message processing.

MONITORING

public static final ServiceProviderConfigurationKeys MONITORING

Set MONITORING frequency in seconds.

Method Detail

values

public static ServiceProviderConfigurationKeys[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (ServiceProviderConfigurationKeys c : ServiceProviderConfigurationKeys.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static ServiceProviderConfigurationKeys valueOf(java.lang.String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

java.lang.IllegalArgumentException - if this enum type has no constant with the specified name

java.lang.NullPointerException - if the argument is null