org.microbean.narayana.jta.cdi

Class DelegatingTransactionSynchronizationRegistry

java.lang.Object

org.microbean.narayana.jta.cdi.DelegatingTransactionSynchronizationRegistry

All Implemented Interfaces:

TransactionSynchronizationRegistry

Direct Known Subclasses:

NarayanaTransactionSynchronizationRegistry

public abstract class DelegatingTransactionSynchronizationRegistry
extends Object
implements TransactionSynchronizationRegistry

An abstract TransactionSynchronizationRegistry implementation that delegates all method invocations to another TransactionSynchronizationRegistry.

Author:

Laird Nelson

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	DelegatingTransactionSynchronizationRegistry(TransactionSynchronizationRegistry delegate) Creates a new DelegatingTransactionSynchronizationRegistry.

Method Summary

Modifier and Type	Method and Description
Object	getResource(Object key) Gest an object from the Map of resources being managed for the transaction bound to the current thread at the time this method is called.
boolean	getRollbackOnly() Get the rollbackOnly status of the transaction bound to the current thread at the time this method is called.
Object	getTransactionKey() Return an opaque object to represent the transaction bound to the current thread at the time this method is called.
int	getTransactionStatus() Return the status of the transaction bound to the current thread at the time this method is called.
void	putResource(Object key, Object value) Adds or replaces an object in the Map of resources being managed for the transaction bound to the current thread at the time this method is called.
void	registerInterposedSynchronization(Synchronization synchronization) Registers a Synchronization instance with special ordering semantics.
void	setRollbackOnly() Sets the rollbackOnly status of the transaction bound to the current thread at the time this method is called.

Methods inherited from class java.lang.Object

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

Constructor Detail

DelegatingTransactionSynchronizationRegistry

protected DelegatingTransactionSynchronizationRegistry(TransactionSynchronizationRegistry delegate)

Creates a new DelegatingTransactionSynchronizationRegistry.

Parameters:

delegate - the TransactionSynchronizationRegistry to which all method invocations will be delegated; must not be null

Throws:

NullPointerException - if delegate is null

Method Detail

getTransactionKey

public Object getTransactionKey()

Return an opaque object to represent the transaction bound to the current thread at the time this method is called.

This method may return null.

This object overrides Object.hashCode() and Object.equals(Object) to allow its use as the key in a Map for use by the caller. If there is no transaction currently active, this method will return null.

The Object returned will return the same hashCode and compare equal to all other objects returned by calling this method from any component executing in the same transaction context in the same application server.

The Object.toString() method returns a String that might be usable by a human reader to usefully understand the transaction context. The Object.toString() result is otherwise not defined. Specifically, there is no forward or backward compatibility guarantee of the results of the returned Object's Object.toString() override.

The object is not necessarily serializable, and has no defined behavior outside the virtual machine whence it was obtained.

Specified by:

getTransactionKey in interface TransactionSynchronizationRegistry

Returns:

an opaque object representing the transaction bound to the current thread at the time this method is called, or null

putResource

public void putResource(Object key,
                        Object value)

Adds or replaces an object in the Map of resources being managed for the transaction bound to the current thread at the time this method is called.

The supplied key should be of an caller-defined class so as not to conflict with other users. The class of the key must guarantee that the hashCode() and equals(Object) methods are suitable for use as keys in a Map. The key and value are not examined or used by the implementation. The general contract of this method is that of Map.put(Object, Object) for a Map that supports non-null keys and null values. For example, if there is already an value associated with the key, it is replaced by the value parameter.

Specified by:

putResource in interface TransactionSynchronizationRegistry

Parameters:

key - the key for the Map entry; must not be null

value - the value for the Map entry

Throws:

IllegalStateException - if no transaction is active

NullPointerException - if the parameter key is null

getResource

public Object getResource(Object key)

Gest an object from the Map of resources being managed for the transaction bound to the current thread at the time this method is called.

The key should have been supplied earlier by a call to putResource(Object, Object) in the same transaction. If the key cannot be found in the current resource Map, null is returned. The general contract of this method is that of Map.get(Object) for a Map that supports non-null keys and null values. For example, the returned value is null if there is no entry for the parameter key or if the value associated with the key is actually null.

Specified by:

getResource in interface TransactionSynchronizationRegistry

Parameters:

key - the key for the Map entry

Returns:

the value associated with the supplied key; may be null

Throws:

IllegalStateException - if no transaction is active

NullPointerException - if the parameter key is null

registerInterposedSynchronization

public void registerInterposedSynchronization(Synchronization synchronization)

Registers a Synchronization instance with special ordering semantics.

The supplied Synchronization's Synchronization.beforeCompletion() method will be called after all SessionSynchronization#beforeCompletion() callbacks and callbacks registered directly with the Transaction, but before the 2-phase commit process starts. Similarly, the Synchronization.afterCompletion(int) callback will be called after 2-phase commit completes but before any SessionSynchronization and Transaction afterCompletion(int) callbacks.

The Synchronization.beforeCompletion() callback will be invoked in the transaction context of the transaction bound to the current thread at the time this method is called. Allowable methods include access to resources, e.g. connectors. No access is allowed to "user components" (e.g. timer services or bean methods), as these might change the state of data being managed by the caller, and might change the state of data that has already been flushed by another caller of registerInterposedSynchronization(Synchronization). The general context is the component context of the caller of registerInterposedSynchronization(Synchronization).

The Synchronization.afterCompletion(int) callback will be invoked in an undefined context. No access is permitted to "user components" as defined above. Resources can be closed but no transactional work can be performed with them.

If this method is invoked without an active transaction context, an IllegalStateException is thrown.

If this method is invoked after the two-phase commit processing has started, an IllegalStateException is thrown.

Specified by:

registerInterposedSynchronization in interface TransactionSynchronizationRegistry

Parameters:

synchronization - the Synchronization to register; must not be null

Throws:

IllegalStateException - if no transaction is active or two-phase commit processing has started

See Also:

Synchronization, Synchronization.beforeCompletion(), Synchronization.afterCompletion(int)

getTransactionStatus

public int getTransactionStatus()

Return the status of the transaction bound to the current thread at the time this method is called.

This is the result of executing TransactionManager.getStatus() in the context of the transaction bound to the current thread at the time this method is called.

Specified by:

getTransactionStatus in interface TransactionSynchronizationRegistry

Returns:

the status of the transaction bound to the current thread at the time this method is called; will be equal the value of one of the constants defined in the Status class

See Also:

TransactionManager.getStatus(), Status

setRollbackOnly

public void setRollbackOnly()

Sets the rollbackOnly status of the transaction bound to the current thread at the time this method is called.

Specified by:

setRollbackOnly in interface TransactionSynchronizationRegistry

Throws:

IllegalStateException - if no transaction is active

getRollbackOnly

public boolean getRollbackOnly()

Get the rollbackOnly status of the transaction bound to the current thread at the time this method is called.

Specified by:

getRollbackOnly in interface TransactionSynchronizationRegistry

Returns:

the rollbackOnly status

Throws:

IllegalStateException - if no transaction is active