KeyAccountingUnit (Flink : Runtime 2.0.0 API)

java.lang.Object
- org.apache.flink.runtime.asyncprocessing.KeyAccountingUnit<K>

Type Parameters:

K - the type of key
```
public class KeyAccountingUnit<K>
extends Object
```
Key accounting unit holds the current in-flight key and tracks the corresponding ongoing records, which is used to preserve the ordering of independent chained StateFuture.

Constructor Summary

Constructors
Constructor Description

KeyAccountingUnit(int initCapacity)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`occupiedCount()`
`boolean`	`occupy(Object record, K key)`	Occupy a key for processing, the subsequent records with the same key would be blocked until the previous key release.
`void`	`release(Object record, K key)`	Release a key, which is invoked when a `RecordContext` is released.

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

- Constructor Detail
  - KeyAccountingUnit
```
public KeyAccountingUnit(int initCapacity)
```
- Method Detail
  - occupy
```
public boolean occupy(Object record,
                      K key)
```
    Occupy a key for processing, the subsequent records with the same key would be blocked until the previous key release.
    
    Returns:
    
    true if no one is occupying this key, and this record succeeds to take it.
  - release
```
public void release(Object record,
                    K key)
```
    Release a key, which is invoked when a RecordContext is released.
  - occupiedCount
```
@VisibleForTesting
public int occupiedCount()
```