com.crankuptheamps.client

Class Message.Options

java.lang.Object

com.crankuptheamps.client.Message.Options

Enclosing class:

Message

public static final class Message.Options
extends java.lang.Object

Represents the possible values for message options in an AMPS command. Options in a message are combined into a comma-delimited list. Each of these option values is comma-terminated, so they can be easily combined by simple string concatenation. For example, to provide the options OOF and NoEmpties to a SOW and Subscribe command, you can use the following code:

 Command c = new Command("sow_and_subscribe")
         .setOptions(Message.Options.OOF +
                 Message.Options.NoEmpties)
 // other parameters for command here
 ;
 

For options that take a list of parameters, this class provides convenience constructors to format the list.

See Also:

Command.getOptions(), Command.setOptions(String), Message.getOptions(), Message.setOptions(String)

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	Cancel Constant string for the cancel option, used when acknowledging (sow_delete) a leased message to return the message to the queue rather than acknowledging the message as processed.
static java.lang.String	Expire Constant string for the expire option, used when acknowledging (sow_delete) a leased message to immediately expire the message from the queue rather than acknowledging the message as processed.
static java.lang.String	FullyDurable Constant string for the fully_durable option.
static java.lang.String	Live Constant string for the live option.
static java.lang.String	NoEmpties Constant string for the no_empties option.
static java.lang.String	None
static java.lang.String	NoSowKey Constant string for the no_sow_key option.
static java.lang.String	OOF Constant string for the oof (out of focus) option.
static java.lang.String	Pause Constant string for the pause option.
static java.lang.String	Replace Constant string for the replace option.
static java.lang.String	Resume Constant string for the resume option.
static java.lang.String	SendKeys Constant string for the send_keys option.
static java.lang.String	Timestamp Constant string for the timestamp option.

Constructor Summary

Constructors

Constructor and Description
Options()

Method Summary

Modifier and Type	Method and Description
static java.lang.String	AckConflationInterval(java.lang.String interval) Formats the ack_conflation interval for a logon command.
static java.lang.String	Conflation(java.lang.String conflation) Formats the conflation option for a command.
static java.lang.String	ConflationKey(java.lang.String conflationKey) Formats the conflation_key option for a command that uses the conflation option.
static java.lang.String	Grouping(java.lang.Iterable<java.lang.String> grouping) Formats the grouping option for an aggregated subscription, which specifies how to determine which records to aggregate together.
static java.lang.String	Grouping(java.lang.String grouping) Formats the grouping option for an aggregated subscription, which specifies how to determine which records to aggregate together.
static java.lang.String	MaxBacklog(int maxBacklog) Formats the max_backlog option for a command, used when subscribing to a queue.
static java.lang.String	Projection(java.lang.Iterable<java.lang.String> projection) Formats the projection option for an aggregated subscription, which specifies the fields produced by the aggregation.
static java.lang.String	Projection(java.lang.String projection) Formats the projection option for an aggregated subscription, which specifies the fields produced by the aggregation.
static java.lang.String	Rate(java.lang.String rate) Formats the rate option for a command, used to slow down the rate of a bookmark replay.
static java.lang.String	RateMaxGap(java.lang.String rateMaxGap) Formats the rate_max_gap option for a command, which can be used when a bookmark replay specifies a relative rate.
static java.lang.String	Select(java.lang.Iterable<java.lang.String> selectList) Formats the select option for a subscription or SOW query, which specifies the fields produced in the delivered messages.
static java.lang.String	Select(java.lang.String selectList) Formats the select option for a subscription or SOW query, which specifies the fields produced in the delivered messages.
static java.lang.String	SkipN(int skipN) Formats the skip_n option for a sow or sow_and_subscribe command.
static java.lang.String	TopN(int topN) Formats the top_n option for a command.

Methods inherited from class java.lang.Object

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

Field Detail

None

public static final java.lang.String None

Live

public static final java.lang.String Live

Constant string for the live option. which requests that a bookmark subscription should receive messages before they are written to the transaction log once replay is complete. This could potentially slightly reduce latency in some configurations, although subscriptions using this option increase the risk of inconsistent data in failover situations.

See Also:

Constant Field Values

OOF

public static final java.lang.String OOF

Constant string for the oof (out of focus) option. When used with a subscription, the oof option requests notification messages when a message that previously matched the subscription no longer matches the subscription.

See Also:

Constant Field Values

Replace

public static final java.lang.String Replace

Constant string for the replace option. When this option is provided on a command, AMPS updates the existing subscription specified in the

 SubId
 

for the command rather than creating a new subscription. See the AMPS User Guide for details.

See Also:

Constant Field Values

NoEmpties

public static final java.lang.String NoEmpties

Constant string for the no_empties option. When used with a delta subscription, this option specifies that AMPS will not create a message to this subscription when a publish happens that does not change the value of any field in the message.

See Also:

Constant Field Values

SendKeys

public static final java.lang.String SendKeys

Constant string for the send_keys option. This option is the current server default, and does not need to be specified. When set, AMPS provides the key fields for a message along with changed fields in messages to a delta subscription.

See Also:

Constant Field Values

Timestamp

public static final java.lang.String Timestamp

Constant string for the timestamp option. When specified on a command, AMPS will include the timestamp header on data messages sent in response to that command.

See Also:

Constant Field Values

NoSowKey

public static final java.lang.String NoSowKey

Constant string for the no_sow_key option. When specified on a command, AMPS will not provide the SOW key field on messages provided in response to the command.

See Also:

Constant Field Values

Cancel

public static final java.lang.String Cancel

Constant string for the cancel option, used when acknowledging (sow_delete) a leased message to return the message to the queue rather than acknowledging the message as processed.

See Also:

Constant Field Values

Expire

public static final java.lang.String Expire

Constant string for the expire option, used when acknowledging (sow_delete) a leased message to immediately expire the message from the queue rather than acknowledging the message as processed.

See Also:

Constant Field Values

Resume

public static final java.lang.String Resume

Constant string for the resume option. This option is to start a set of bookmark subscriptions that have been entered in a paused state. See the AMPS User Guide for details.

See Also:

Constant Field Values

Pause

public static final java.lang.String Pause

Constant string for the pause option. This option is used to group bookmark subscriptions so that a set of independent subscriptions can be started simultaneously and proceed through replay together, typically used for testing or auditing purposes. See the AMPS User Guide for details.

See Also:

Constant Field Values

FullyDurable

public static final java.lang.String FullyDurable

Constant string for the fully_durable option. This option specifies that a message will not be provided to a bookmark replay until it has been acknowledged as persisted by all synchronous replication destinations. The option is used to provide increased repeatability of bookmark subscriptions, although it may increase the latency for current publishes to be delivered to the subscriber due to the persistence requirement.

See Also:

Constant Field Values

Constructor Detail

Options

public Options()

Method Detail

Conflation

public static java.lang.String Conflation(java.lang.String conflation)

Formats the conflation option for a command. This option can be used with subscriptions to topics in the State-of-the-World to request that AMPS conflate publishes to the same record. This can reduce bandwidth and processing requirements for the the subscriber. If a large number of subscribers will use the same conflation setting for the same topic, consider configuring a ConflatedTopic on the server. See the AMPS User Guide for details.

Parameters:

conflation - the conflation interval

Returns:

the formatted value

ConflationKey

public static java.lang.String ConflationKey(java.lang.String conflationKey)

Formats the conflation_key option for a command that uses the conflation option. This option can be used with subscriptions to topics in the State-of-the-World to request that AMPS conflate publishes to messages with a common value for a field or set of fields that is not the key for the topic. This option must be used with the conflation option.

Parameters:

conflationKey - the field or fields to use as a conflation key

Returns:

the formatted value

TopN

public static java.lang.String TopN(int topN)

Formats the top_n option for a command. When this option is specified, AMPS will return the specified number of messages from the results. See the AMPS Command Reference for details.

Parameters:

topN - the number of messages to return from the result set

Returns:

the formatted value

SkipN

public static java.lang.String SkipN(int skipN)

Formats the skip_n option for a sow or sow_and_subscribe command. When this option is provided, AMPS will skip the specified number of messages before returning the top_n records specified. See the AMPS Command Reference and the Developer Guide for details.

Parameters:

skipN - the number of results to skip before beginning to return results

Returns:

the formatted value

MaxBacklog

public static java.lang.String MaxBacklog(int maxBacklog)

Formats the max_backlog option for a command, used when subscribing to a queue. When consuming from a queue, this option sets the maximum number of messages the client is willing to have outstanding at a given time. (The actual number of messages provided is determined by both this parameter and the server configuration.) See the AMPS User Guide and the AMPS Command Reference for details.

Parameters:

maxBacklog - the maximum number of messages to provide to this subscription at a given time

Returns:

the formatted value

Rate

public static java.lang.String Rate(java.lang.String rate)

Formats the rate option for a command, used to slow down the rate of a bookmark replay. When used with a bookmark replay, this option directs AMPS to slow down the replay to approximately the rate specified. See the AMPS Command Reference for details.

Parameters:

rate - the requested rate limit for the bookmark replay

Returns:

the formatted value

RateMaxGap

public static java.lang.String RateMaxGap(java.lang.String rateMaxGap)

Formats the rate_max_gap option for a command, which can be used when a bookmark replay specifies a relative rate. When used with a bookmark replay that specifies a relative rate (for example, that the replay should be slowed down to no more than 2X the original publish rate), this option sets the maximum amount of time for the replay to go without producing a message. See the AMPS User Guide for details.

Parameters:

rateMaxGap - the maximum amount of time without producing a message

Returns:

the formatted value

Select

public static java.lang.String Select(java.lang.String selectList)

Formats the select option for a subscription or SOW query, which specifies the fields produced in the delivered messages. This overload of the method expects a string that contains a comma-delimited list of field directives. See the AMPS User Guide for details.

Parameters:

selectList - the list of fields to produce

Returns:

the formatted value

Select

public static java.lang.String Select(java.lang.Iterable<java.lang.String> selectList)

Formats the select option for a subscription or SOW query, which specifies the fields produced in the delivered messages. This overload of the method expects a Iterable that contains individual field directives. The method formats the field directives into a comma-delimited list. See the AMPS User Guide for details.

Parameters:

selectList - a list of fields to produce

Returns:

the formatted value

Projection

public static java.lang.String Projection(java.lang.String projection)

Formats the projection option for an aggregated subscription, which specifies the fields produced by the aggregation. When this option is provided, a grouping option must also be provided. This overload of the method expects a string that contains a comma-delimited list of projections. See the AMPS User Guide for details.

Parameters:

projection - the fields to produce

Returns:

the formatted value

Projection

public static java.lang.String Projection(java.lang.Iterable<java.lang.String> projection)

Formats the projection option for an aggregated subscription, which specifies the fields produced by the aggregation. When this option is provided, a grouping option must also be provided. This overload of the method expects a Iterable that contains individual field projections. The method formats the field projections into a comma-delimited list. See the AMPS User Guide for details.

Parameters:

projection - a list of fields to produce

Returns:

the formatted value

Grouping

public static java.lang.String Grouping(java.lang.String grouping)

Formats the grouping option for an aggregated subscription, which specifies how to determine which records to aggregate together. When this option is provided, a projection option must also be provided. This overload of the method expects a String that contains a comma-delimited list of fields to group by. See the AMPS User Guide for details.

Parameters:

grouping - the fields to group by

Returns:

the formatted value

Grouping

public static java.lang.String Grouping(java.lang.Iterable<java.lang.String> grouping)

Formats the grouping option for an aggregated subscription, which specifies how to determine which records to aggregate together. When this option is provided, a projection option must also be provided. This overload of the method expects a Iterable that contains individual fields. This method formats the contents of the Iterable into a comma-delimited list. See the AMPS User Guide for details.

Parameters:

grouping - the list of fields to group by

Returns:

the formatted value

AckConflationInterval

public static java.lang.String AckConflationInterval(java.lang.String interval)

Formats the ack_conflation interval for a logon command. This option can be used to request that, for this connection, the server return persisted acknowledgements for publishes more frequently than the default 1s interval. Notice that, if the server replicates messages to other destinations, the effective conflation interval may depend on the replication configuration of this server and the replication configuration of the destinations that this server replicates to: AMPS will not provide a persisted acknowledgment for a message that has not been properly acknowledged by the applicable replication destinations. This option is only valid on a logon command.

Parameters:

interval - the interval at which to conflate persisted publish acknowledgements for this connection

Returns:

the formatted value