org.apache.hadoop.io.retry
Class RetryUtils

java.lang.Object
  extended by org.apache.hadoop.io.retry.RetryUtils

public class RetryUtils
extends Object


Field Summary
static org.apache.commons.logging.Log LOG
           
 
Constructor Summary
RetryUtils()
           
 
Method Summary
static RetryPolicy getDefaultRetryPolicy(Configuration conf, String retryPolicyEnabledKey, boolean defaultRetryPolicyEnabled, String retryPolicySpecKey, String defaultRetryPolicySpec, Class<? extends Exception> remoteExceptionToRetry)
          Return the default retry policy set in conf.
static RetryPolicy getMultipleLinearRandomRetry(Configuration conf, String retryPolicyEnabledKey, boolean defaultRetryPolicyEnabled, String retryPolicySpecKey, String defaultRetryPolicySpec)
          Return the MultipleLinearRandomRetry policy specified in the conf, or null if the feature is disabled.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

LOG

public static final org.apache.commons.logging.Log LOG
Constructor Detail

RetryUtils

public RetryUtils()
Method Detail

getDefaultRetryPolicy

public static RetryPolicy getDefaultRetryPolicy(Configuration conf,
                                                String retryPolicyEnabledKey,
                                                boolean defaultRetryPolicyEnabled,
                                                String retryPolicySpecKey,
                                                String defaultRetryPolicySpec,
                                                Class<? extends Exception> remoteExceptionToRetry)
Return the default retry policy set in conf. If the value retryPolicyEnabledKey is set to false in conf, use TRY_ONCE_THEN_FAIL. Otherwise, get the MultipleLinearRandomRetry policy specified in the conf and then (1) use multipleLinearRandomRetry for - remoteExceptionToRetry, or - IOException other than RemoteException; and (2) use TRY_ONCE_THEN_FAIL for - RemoteException other than remoteExceptionToRetry, or - non-IOException.

Parameters:
conf -
retryPolicyEnabledKey - conf property key for enabling retry
defaultRetryPolicyEnabled - default retryPolicyEnabledKey conf value
retryPolicySpecKey - conf property key for retry policy spec
defaultRetryPolicySpec - default retryPolicySpecKey conf value
remoteExceptionToRetry - The particular RemoteException to retry
Returns:
the default retry policy.

getMultipleLinearRandomRetry

public static RetryPolicy getMultipleLinearRandomRetry(Configuration conf,
                                                       String retryPolicyEnabledKey,
                                                       boolean defaultRetryPolicyEnabled,
                                                       String retryPolicySpecKey,
                                                       String defaultRetryPolicySpec)
Return the MultipleLinearRandomRetry policy specified in the conf, or null if the feature is disabled. If the policy is specified in the conf but the policy cannot be parsed, the default policy is returned. Retry policy spec: N pairs of sleep-time and number-of-retries "s1,n1,s2,n2,..."

Parameters:
conf -
retryPolicyEnabledKey - conf property key for enabling retry
defaultRetryPolicyEnabled - default retryPolicyEnabledKey conf value
retryPolicySpecKey - conf property key for retry policy spec
defaultRetryPolicySpec - default retryPolicySpecKey conf value
Returns:
the MultipleLinearRandomRetry policy specified in the conf, or null if the feature is disabled.


Copyright © 2009 The Apache Software Foundation