org.everit.osgi.transaction.helper.api

Interface TransactionHelper

All Known Implementing Classes:

TransactionHelperComponent, TransactionHelperImpl

public interface TransactionHelper

TransactionHelper OSGi service can be used to manipulate transactions on the current thread. The methods of this service can be used with normal Callback objects, anonymous classes or lambda expressions.

Method Summary

Modifier and Type	Method and Description
<R> R	mandatory(java.util.function.Supplier<R> callback) Support a current transaction, throw an exception if none exists.
<R> R	never(java.util.function.Supplier<R> callback) Execute non-transactionally, throw an exception if a transaction exists.
<R> R	notSupported(java.util.function.Supplier<R> callback) Execute non-transactionally, suspend the current transaction if one exists.
<R> R	required(java.util.function.Supplier<R> callback) Support a current transaction, create a new one if none exists.
<R> R	requiresNew(java.util.function.Supplier<R> callback) Create a new transaction, suspend the current transaction if one exists.
<R> R	supports(java.util.function.Supplier<R> callback) Support a current transaction, execute non-transactionally if none exists.

Method Detail

mandatory

<R> R mandatory(java.util.function.Supplier<R> callback)

Support a current transaction, throw an exception if none exists. In case there is an exception in the callback, the transaction status is set to MARKED_ROLLBACK.

Type Parameters:

R - Return type.

Parameters:

callback - The callback instance will be called inside.

Returns:

The result of the callback execution.

Throws:

IllegalStateException - if there is no active transaction.

never

<R> R never(java.util.function.Supplier<R> callback)

Execute non-transactionally, throw an exception if a transaction exists.

Type Parameters:

R - Return type.

Parameters:

callback - The callback instance will be called inside.

Returns:

The result of the callback execution.

Throws:

IllegalStateException - if the status of the current thread is different from Status.STATUS_NO_TRANSACTION.

notSupported

<R> R notSupported(java.util.function.Supplier<R> callback)

Execute non-transactionally, suspend the current transaction if one exists.

Type Parameters:

R - Return type.

Parameters:

callback - The callback instance will be called inside.

Returns:

The result of the callback execution.

Throws:

IllegalStateException - if the transaction status at the time of calling this function is neither Status.STATUS_ACTIVE nor Status.STATUS_NO_TRANSACTION.

required

<R> R required(java.util.function.Supplier<R> callback)

Support a current transaction, create a new one if none exists. In case there is an exception in the callback and the function call created the transaction, the transaction will be rollbacked. In case there is an exception and there was already a transaction when the method was called, the transaction status is set to MARKED_ROLLBACK.

Type Parameters:

R - Return type.

Parameters:

callback - The callback instance will be called inside.

Returns:

The result of the callback execution.

Throws:

IllegalStateException - if the transaction status at the time of calling this function is neither Status.STATUS_ACTIVE nor Status.STATUS_NO_TRANSACTION.

requiresNew

<R> R requiresNew(java.util.function.Supplier<R> callback)

Create a new transaction, suspend the current transaction if one exists. In case there is an exception, the newly created transaction will be rolled back.

Type Parameters:

R - Return type.

Parameters:

callback - The callback instance will be called inside.

Returns:

The result of the callback execution.

supports

<R> R supports(java.util.function.Supplier<R> callback)

Support a current transaction, execute non-transactionally if none exists. If there was an ACTIVE transaction at the time calling the function and the callback throws an exception, the transaction status will be MARKED_ROLLBACK.

Type Parameters:

R - Return type.

Parameters:

callback - The callback instance will be called inside.

Returns:

The result of the callback execution.

Throws:

IllegalStateException - if the transaction status at the time of calling this function is neither Status.STATUS_ACTIVE nor Status.STATUS_NO_TRANSACTION.