com.datastax.driver.core.policies

Interface ExtendedRetryPolicy

All Superinterfaces:

RetryPolicy

All Known Implementing Classes:

DefaultRetryPolicy, DowngradingConsistencyRetryPolicy, FallthroughRetryPolicy, IdempotenceAwareRetryPolicy, LoggingRetryPolicy

public interface ExtendedRetryPolicy
extends RetryPolicy

A policy that defines a default behavior to adopt in the event of unexpected errors.

This interface exists only for backward compatibility reasons: its methods should really be defined by RetryPolicy, but adding it after the fact would break binary compatibility. It should be merged into RetryPolicy in the next major release.

All retry policies shipped with the driver implement this interface.

Nested Class Summary

Nested classes/interfaces inherited from interface com.datastax.driver.core.policies.RetryPolicy

RetryPolicy.RetryDecision

Method Summary

Modifier and Type	Method and Description
RetryPolicy.RetryDecision	onRequestError(Statement statement, ConsistencyLevel cl, Exception e, int nbRetry) Defines whether to retry and at which consistency level on an unexpected error.

Methods inherited from interface com.datastax.driver.core.policies.RetryPolicy

onReadTimeout, onUnavailable, onWriteTimeout

Method Detail

onRequestError

RetryPolicy.RetryDecision onRequestError(Statement statement,
                                         ConsistencyLevel cl,
                                         Exception e,
                                         int nbRetry)

Defines whether to retry and at which consistency level on an unexpected error.

This method might be invoked in the following situations:

1. On a client timeout, while waiting for the server response (see SocketOptions.getReadTimeoutMillis());
2. On a connection error (socket closed, etc.);
3. When the contacted host replies with an error, such as OVERLOADED, IS_BOOTSTRAPPING, SERVER_ERROR, etc.

Note that when this method is invoked, the driver cannot guarantee that the mutation has been effectively applied server-side; a retry should only be attempted if the request is known to be idempotent.

Parameters:

statement - the original query that failed.

cl - the requested consistency level for the operation. Note that this is not necessarily the achieved consistency level (if any), and it is never a serial one.

e - the exception that caused this request to fail.

nbRetry - the number of retries already performed for this operation.

Returns:

the retry decision. If RetryDecision.RETHROW is returned, the DriverException passed to this method will be thrown for the operation.