Package com.storedobject.job

Class MessageSender<T extends Message>

java.lang.Object

com.storedobject.job.Job

com.storedobject.job.DaemonJob

com.storedobject.job.MessageSender<T>

Type Parameters:

T - Type of message.

Direct Known Subclasses:

Server, Server, Server

public abstract class MessageSender<T extends Message>
extends DaemonJob

Message sender.

Note: All message senders (SMS, Email, Telegram etc.) must extend this class.

Author:

Syam

Constructor Summary

Constructors

Constructor	Description
MessageSender(Schedule schedule, Class<T> messageClass)	Constructor.

Method Summary

Modifier and Type	Method	Description
protected boolean	canSend(T message)	Is it possible to send this message?
final void	execute()	Execute the Job.
protected int	getBatchSize()	Batch size - How many messages to be read for sending in one batch?
protected int	getCreditBalance()	Get the current credit balance.
protected int	getDeliveryCost(T message)	Get the number of credits required to deliver this message.
protected String	getSelectCondition()	Additional condition to be be added when messages are read for sending.
protected void	initialize()	This method is invoked when this job is executed for the first time, and it will be invoked only once.
static void	kick()	Kick all active "message senders" to indicate that some new messages are available for sending.
protected boolean	monitorDeliveryCost()	Check if we need to monitor delivery cost or not.
protected void	recover()	This method is invoked when the sender was stopped due to any error.
protected abstract int	sendMessage(T message)	Send a message.
protected boolean	sendMessages(List<T> messages)	Send a batch of messages.
final void	shutdown()	This method is invoked when the system is shutting down.
protected void	terminate()	This method is invoked when the sender needs to be shut down.

Methods inherited from class com.storedobject.job.DaemonJob

isActive

Methods inherited from class com.storedobject.job.Job

alert, clean, getDevice, getStatus, getTransactionManager, log

Methods inherited from class java.lang.Object

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

Constructor Details

MessageSender

public MessageSender(Schedule schedule,
 Class<T> messageClass)

Constructor.

Parameters:

schedule - Schedule defined for this Job.

messageClass - Message class.

Method Details

initialize

protected void initialize()

This method is invoked when this job is executed for the first time, and it will be invoked only once. You may set up the sender here.

recover

protected void recover()

This method is invoked when the sender was stopped due to any error. Make sure that DaemonJob.isActive() method returns false to indicate that the sender had stopped with some error condition. All recovery action should happen here and the DaemonJob.isActive() method should return true after this. Otherwise, no messages will be sent by invoking the sendMessage(Message) method.

execute

public final void execute()
                   throws Throwable

Description copied from class: Job

Execute the Job.

Specified by:

execute in class Job

Throws:

Throwable - If an error is thrown from this method, execution is terminated and the details of the error will be logged.

kick

public static void kick()

Kick all active "message senders" to indicate that some new messages are available for sending.

shutdown

public final void shutdown()

Description copied from class: Job

This method is invoked when the system is shutting down. It will be called even if the job is inactive at that time. (The default implementation does nothing).

Overrides:

shutdown in class Job

terminate

protected void terminate()

This method is invoked when the sender needs to be shut down. This will be invoked only once.

getSelectCondition

protected String getSelectCondition()

Additional condition to be be added when messages are read for sending.

Returns:

Default implementation returns null, so no additional selection criteria are applied.

monitorDeliveryCost

protected boolean monitorDeliveryCost()

Check if we need to monitor delivery cost or not.

Note: Applicable mostly to SMS messages.

Returns:

True/false.

getCreditBalance

protected int getCreditBalance()

Get the current credit balance.

Note: Applicable mostly to SMS messages.

Returns:

Current credit balance.

getDeliveryCost

protected int getDeliveryCost(T message)

Get the number of credits required to deliver this message.

Note: Applicable mostly to SMS messages.

Parameters:

message - Message to send.

Returns:

Cost (in number of credits).

sendMessages

protected boolean sendMessages(List<T> messages)

Send a batch of messages. The default implementation of this method process each message by invoking sendMessage(Message) and if this is overridden, the sendMessage(Message) will not be invoked from elsewhere.

Note: Status of the message should be updated adn saved within this method if overridden.

Parameters:

messages - Messages to be sent.

Returns:

True if messages are sent successfully.

sendMessage

protected abstract int sendMessage(T message)

Send a message. The method should just send the message and should not update any status.

Parameters:

message - Message to send.

Returns:

The error code to indicate the status. 0: Successful, 1: Retry later, 2: Insufficient balance. Anything above 2 indicates an error condition that doesn't allow this message to be sent (for example: invalid mobile number in case of an SMSMessage).

getBatchSize

protected int getBatchSize()

Batch size - How many messages to be read for sending in one batch?

Returns:

Default is 50.

canSend

protected boolean canSend(T message)

Is it possible to send this message?

Parameters:

message - Message.

Returns:

True/false.