com.tailf.dp.annotations

Class TransCallbackProxy

Object

com.tailf.dp.annotations.TransCallbackProxy

All Implemented Interfaces:

DpTransCallback

public class TransCallbackProxy
extends Object
implements DpTransCallback

Callback proxy for Trans Callbacks. Implements the DpTransCallback interface and delegates calls to the registered callback POJO with annotated methods

Since:

3.2.0

Field Summary

Fields inherited from interface com.tailf.dp.DpTransCallback

M_ABORT, M_ALL, M_COMMIT, M_FINISH, M_INIT, M_PREPARE, M_TRANS_LOCK, M_TRANS_UNLOCK, M_WRITE_START

Constructor Summary

Constructors

Constructor and Description
TransCallbackProxy(Object backupObject) Constructor for Callback proxys.

Method Summary

Modifier and Type	Method and Description
void	abort(DpTrans trans) This callback is responsible for undoing whatever was done in the prepare() phase.
void	addActionCapability(TransCBType transCBType) Add action capability from annotated callType used to register capabilities on the server
void	addActionMethod(String name, Method method) Add callback action method to proxy
void	commit(DpTrans trans) This callback is responsible for undoing whatever was done in the prepare() phase.
void	finish(DpTrans trans) This callback is responsible for releasing resources allocated in the init() phase.
Object	getBackupObject() Retrieve the callback POJO
static TransCallbackProxy[]	getTransCallbackProxys(Object obj) Get array of proxy objects from registered POJO callback.
void	init(DpTrans trans) The callback must indicate which WORKER_SOCKET should be used for future communications in this transaction.
int	mask() Mask of flags for each method that is supported by this callback: DpTransCallback.M_INIT DpTransCallback.M_TRANS_LOCK DpTransCallback.M_TRANS_UNLOCK DpTransCallback.M_WRITE_START DpTransCallback.M_PREPARE DpTransCallback.M_ABORT DpTransCallback.M_COMMIT DpTransCallback.M_FINISH
void	prepare(DpTrans trans) If we have multiple sources of data it is highly recommended that the callback is implemented.
void	transLock(DpTrans trans) This callback is invoked when the validation phase of the transaction starts.
void	transUnlock(DpTrans trans) This callback is called when the validation of the transaction failed, or the validation is triggered explicitly (i.e.
void	writeStart(DpTrans trans) This callback is invoked when the validation succeeded and the write phase of the transaction starts.

Methods inherited from class Object

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

Constructor Detail

TransCallbackProxy

public TransCallbackProxy(Object backupObject)

Constructor for Callback proxys. Used internally.

Parameters:

backupObject - registered callback POJO

Method Detail

getBackupObject

public Object getBackupObject()

Retrieve the callback POJO

Returns:

Object registered callback object

addActionMethod

public void addActionMethod(String name,
                            Method method)

Add callback action method to proxy

Parameters:

name - canonical action name

method - registered callback method

addActionCapability

public void addActionCapability(TransCBType transCBType)

Add action capability from annotated callType used to register capabilities on the server

Parameters:

transCBType - action type

abort

public void abort(DpTrans trans)
           throws DpCallbackException

Description copied from interface: DpTransCallback

This callback is responsible for undoing whatever was done in the prepare() phase.

Specified by:

abort in interface DpTransCallback

Parameters:

trans - Transaction

Throws:

DpCallbackException - Callback method failed.

commit

public void commit(DpTrans trans)
            throws DpCallbackException

Description copied from interface: DpTransCallback

This callback is responsible for undoing whatever was done in the prepare() phase.

Specified by:

commit in interface DpTransCallback

Parameters:

trans - Transaction

Throws:

DpCallbackException - Callback method failed.

finish

public void finish(DpTrans trans)
            throws DpCallbackException

Description copied from interface: DpTransCallback

This callback is responsible for releasing resources allocated in the init() phase.

Specified by:

finish in interface DpTransCallback

Parameters:

trans - Transaction

Throws:

DpCallbackException - Callback method failed.

init

public void init(DpTrans trans)
          throws DpCallbackException

Description copied from interface: DpTransCallback

The callback must indicate which WORKER_SOCKET should be used for future communications in this transaction. This is the mechanism which is used by Conf to distribute work among multiple worker threads in the database application.

Specified by:

init in interface DpTransCallback

Parameters:

trans - Transaction

Throws:

DpCallbackException - Callback method failed.

mask

public int mask()

Description copied from interface: DpTransCallback

Mask of flags for each method that is supported by this callback:

• DpTransCallback.M_INIT
• DpTransCallback.M_TRANS_LOCK
• DpTransCallback.M_TRANS_UNLOCK
• DpTransCallback.M_WRITE_START
• DpTransCallback.M_PREPARE
• DpTransCallback.M_ABORT
• DpTransCallback.M_COMMIT
• DpTransCallback.M_FINISH

Specified by:

mask in interface DpTransCallback

prepare

public void prepare(DpTrans trans)
             throws DpCallbackException

Description copied from interface: DpTransCallback

If we have multiple sources of data it is highly recommended that the callback is implemented. The callback is called at the end of the transaction, when all read and write operations for the transaction have been performed and the transaction should prepare to commit.

Specified by:

prepare in interface DpTransCallback

Parameters:

trans - Transaction

Throws:

DpCallbackException - Callback method failed.

transLock

public void transLock(DpTrans trans)
               throws DpCallbackException

Description copied from interface: DpTransCallback

This callback is invoked when the validation phase of the transaction starts. If the underlying database supports real transactions, it is usually appropriate to start such a native transaction here.

The transaction enters VALIDATE state, where the system will perform a series of read() operations.

The trans lock is set until either transUnlock() or finish() is called. the system ensures that a transLock is set on a single transaction only.

Specified by:

transLock in interface DpTransCallback

Parameters:

trans - Transaction

Throws:

DpCallbackException - Callback method failed.

transUnlock

public void transUnlock(DpTrans trans)
                 throws DpCallbackException

Description copied from interface: DpTransCallback

This callback is called when the validation of the transaction failed, or the validation is triggered explicitly (i.e. not part of a user can enter invalid data. Transactions that originate from NETCONF will never trigger this callback. If the underlying database supports real transactions and they are used, the transaction should be aborted here.

The transaction re-enters READ state.

Specified by:

transUnlock in interface DpTransCallback

Parameters:

trans - Transaction

Throws:

DpCallbackException - Callback method failed.

writeStart

public void writeStart(DpTrans trans)
                throws DpCallbackException

Description copied from interface: DpTransCallback

This callback is invoked when the validation succeeded and the write phase of the transaction starts. If the underlying database supports real transactions, it is usually appropriate to start such a native transaction here.

The transaction enters the WRITE state. No more read() operations will be performed by the system.

Specified by:

writeStart in interface DpTransCallback

Parameters:

trans - Transaction

Throws:

DpCallbackException - Callback method failed.

getTransCallbackProxys

public static TransCallbackProxy[] getTransCallbackProxys(Object obj)
                                                   throws DpCallbackException

Get array of proxy objects from registered POJO callback. Used internally at callback registration

Parameters:

obj - registered Callback POJO

Returns:

array of TransCallbackProxy

Throws:

DpCallbackException