Callback.CallChain (atlasdb-commons 0.528.0 API)

java.lang.Object
- com.palantir.async.initializer.Callback<T>
- - com.palantir.async.initializer.Callback.CallChain<T>

Enclosing class:

Callback<R>
```
public static class Callback.CallChain<T>
extends Callback<T>
```
A CallChain executes a list of callbacks in sequence. Note that a given callback is executed only once all previous callbacks in the chain have successfully executed. Also, callbacks are retried independently. In other words, given a CallChain of two callbacks C1 and C2:
- C1 is executed first. If it fails, C1's cleanup will be invoked, and then C1 will be retried.
- C2 is then executed. If it fails, C2's cleanup will be invoked and then C2 will be retried. (Note that we will not re-invoke C1's cleanup, nor will we execute it again.) Once C2 succeeds, the CallChain as a whole will be treated as complete.
Please see the examples in CallChainTest for more detail.

Nested Class Summary
- Nested classes/interfaces inherited from class com.palantir.async.initializer.Callback
  Callback.CallChain<T>

Constructor Summary

Constructors
Constructor Description

CallChain(Callback<T>... callbacks)

CallChain(List<Callback<T>> callbacks)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`cleanup(T resource, Throwable cleanupException)`	Cleanup to be done if init() throws, before init() can be attempted again.
`void`	`init(T resource)`	The method to be executed.

Methods inherited from class com.palantir.async.initializer.Callback
blockUntilSafeToShutdown, noOp, runOnceOnly, runWithRetry

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - CallChain
```
public CallChain(List<Callback<T>> callbacks)
```
  - CallChain
```
public CallChain(Callback<T>... callbacks)
```
- Method Detail
  - init
```
public void init(T resource)
```
    Description copied from class: Callback
    
    The method to be executed. If init() returns, the callback is considered to be successful.
    
    Specified by:
    
    init in class Callback<T>
  - cleanup
```
public void cleanup(T resource,
                    Throwable cleanupException)
```
    Description copied from class: Callback
    
    Cleanup to be done if init() throws, before init() can be attempted again. If this method throws, runWithRetry() will fail and init() will not be retried. The default implementation assumes that init() throwing is terminal and there is no cleanup necessary. This should be overridden by specifying any cleanup steps necessary, and the method must return instead of throwing if init() can be retried
    
    Overrides:
    
    cleanup in class Callback<T>
    
    cleanupException - Throwable thrown by init()