Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance. Project price only 1 $
You can buy this project and download/modify it how often you want.
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.io.retry;
import java.io.IOException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.ipc.RemoteException;
import com.google.protobuf.ServiceException;
import org.apache.hadoop.ipc.RetriableException;
public class RetryUtils {
public static final Log LOG = LogFactory.getLog(RetryUtils.class);
/**
* 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, or
* - ServiceException; and
* (2) use TRY_ONCE_THEN_FAIL for
* - non-remoteExceptionToRetry RemoteException, or
* - non-IOException.
*
*
* @param conf
* @param retryPolicyEnabledKey conf property key for enabling retry
* @param defaultRetryPolicyEnabled default retryPolicyEnabledKey conf value
* @param retryPolicySpecKey conf property key for retry policy spec
* @param defaultRetryPolicySpec default retryPolicySpecKey conf value
* @param remoteExceptionToRetry The particular RemoteException to retry
* @return the default retry policy.
*/
public static RetryPolicy getDefaultRetryPolicy(
Configuration conf,
String retryPolicyEnabledKey,
boolean defaultRetryPolicyEnabled,
String retryPolicySpecKey,
String defaultRetryPolicySpec,
final Class remoteExceptionToRetry
) {
final RetryPolicy multipleLinearRandomRetry =
getMultipleLinearRandomRetry(
conf,
retryPolicyEnabledKey, defaultRetryPolicyEnabled,
retryPolicySpecKey, defaultRetryPolicySpec
);
if (LOG.isDebugEnabled()) {
LOG.debug("multipleLinearRandomRetry = " + multipleLinearRandomRetry);
}
if (multipleLinearRandomRetry == null) {
//no retry
return RetryPolicies.TRY_ONCE_THEN_FAIL;
} else {
return new RetryPolicy() {
@Override
public RetryAction shouldRetry(Exception e, int retries, int failovers,
boolean isMethodIdempotent) throws Exception {
if (e instanceof ServiceException) {
//unwrap ServiceException
final Throwable cause = e.getCause();
if (cause != null && cause instanceof Exception) {
e = (Exception)cause;
}
}
//see (1) and (2) in the javadoc of this method.
final RetryPolicy p;
if (e instanceof RetriableException
|| RetryPolicies.getWrappedRetriableException(e) != null) {
// RetriableException or RetriableException wrapped
p = multipleLinearRandomRetry;
} else if (e instanceof RemoteException) {
final RemoteException re = (RemoteException)e;
p = remoteExceptionToRetry.getName().equals(re.getClassName())?
multipleLinearRandomRetry: RetryPolicies.TRY_ONCE_THEN_FAIL;
} else if (e instanceof IOException || e instanceof ServiceException) {
p = multipleLinearRandomRetry;
} else { //non-IOException
p = RetryPolicies.TRY_ONCE_THEN_FAIL;
}
if (LOG.isDebugEnabled()) {
LOG.debug("RETRY " + retries + ") policy="
+ p.getClass().getSimpleName() + ", exception=" + e);
}
return p.shouldRetry(e, retries, failovers, isMethodIdempotent);
}
@Override
public String toString() {
return "RetryPolicy[" + multipleLinearRandomRetry + ", "
+ RetryPolicies.TRY_ONCE_THEN_FAIL.getClass().getSimpleName()
+ "]";
}
};
}
}
/**
* 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,..."
*
* @param conf
* @param retryPolicyEnabledKey conf property key for enabling retry
* @param defaultRetryPolicyEnabled default retryPolicyEnabledKey conf value
* @param retryPolicySpecKey conf property key for retry policy spec
* @param defaultRetryPolicySpec default retryPolicySpecKey conf value
* @return the MultipleLinearRandomRetry policy specified in the conf,
* or null if the feature is disabled.
*/
public static RetryPolicy getMultipleLinearRandomRetry(
Configuration conf,
String retryPolicyEnabledKey,
boolean defaultRetryPolicyEnabled,
String retryPolicySpecKey,
String defaultRetryPolicySpec
) {
final boolean enabled =
conf.getBoolean(retryPolicyEnabledKey, defaultRetryPolicyEnabled);
if (!enabled) {
return null;
}
final String policy = conf.get(retryPolicySpecKey, defaultRetryPolicySpec);
final RetryPolicy r =
RetryPolicies.MultipleLinearRandomRetry.parseCommaSeparatedString(
policy);
return (r != null) ?
r :
RetryPolicies.MultipleLinearRandomRetry.parseCommaSeparatedString(
defaultRetryPolicySpec);
}
}
