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| |
| <p> |
| A mechanism for selectively retrying methods that throw exceptions under certain circumstances. |
| </p> |
| |
| <p> |
| Typical usage is |
| </p> |
| |
| <pre> |
| UnreliableImplementation unreliableImpl = new UnreliableImplementation(); |
| UnreliableInterface unreliable = (UnreliableInterface) |
| RetryProxy.create(UnreliableInterface.class, unreliableImpl, |
| RetryPolicies.retryUpToMaximumCountWithFixedSleep(4, 10, TimeUnit.SECONDS)); |
| unreliable.call(); |
| </pre> |
| |
| <p> |
| This will retry any method called on <code>unreliable</code> four times - in this case the <code>call()</code> |
| method - sleeping 10 seconds between |
| each retry. There are a number of {@link org.apache.hadoop.io.retry.RetryPolicies retry policies} |
| available, or you can implement a custom one by implementing {@link org.apache.hadoop.io.retry.RetryPolicy}. |
| It is also possible to specify retry policies on a |
| {@link org.apache.hadoop.io.retry.RetryProxy#create(Class, Object, Map) per-method basis}. |
| </p> |
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