All Implemented Interfaces:
```
public final class StagingArea

                    
```
Staged, atomically-published writes (HEL-236 guarantee 2). Object storage has NO atomic rename, so atomicity is constructed from the primitives it does have:
- every artifact is first written under a run-scoped STAGING prefix (<prefix>/.staging/<runId>/…) that readers never look at;
- staged objects are server-side COPIED to their run-scoped final keys — still invisible, because readers only trust manifests;
- the manifest is PUT with WriteCondition.IfAbsent — this single conditional create IS the commit point: before it, the dataset does not exist; after it, it is complete (the manifest names every part);
- staging is deleted.
A crash anywhere before step 3 leaves only invisible garbage, never a half-published dataset. Losing the step-3 race (PreconditionFailedException) rolls back this run's copies deterministically. Abandoned staging has a DETERMINISTIC ownership/cleanup rule: a run owns .staging/<runId>/, and cleanupAbandoned deletes any run whose newest object is older than the caller's threshold (a live writer keeps its staging young by writing).
Requires StorageCapability.CONDITIONAL_CREATE; the constructor rejects a provider without it BEFORE any data movement.

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description

Field Summary

Fields
Modifier and Type	Field	Description
`public final static String`	`STAGING_SEGMENT`
`private final String`	`stagingPrefix`
`private final String`	`finalPrefix`
`private final String`	`runId`

Constructor Summary

Constructors
Constructor	Description
`StagingArea(ObjectStore store, String finalPrefix, String runId, Clock clock)`

Enum Constant Summary

Enum Constants
Enum Constant	Description

Method Summary

Modifier and Type	Method	Description
`final String`	`getStagingPrefix()`
`final String`	`getFinalPrefix()`
`final String`	`getRunId()`
`final ObjectKey`	`stageKey(String name)`	The staging key for a run-relative artifact name.
`final PutResult`	`stage(String name, ContentSource source, PutOptions options)`	Write one artifact into staging (delegates to ObjectStore.put).
`final List<ObjectSummary>`	`stagedObjects()`	Everything currently staged for THIS run.
`final PutResult`	`publish(Map<ObjectKey, ObjectKey> plan, ObjectKey manifestKey, ContentSource manifestBody, PutOptions manifestOptions)`	Commit: copy each staged object to its final key per plan, then create manifestKey conditionally, then drop staging.
`final Long`	`discard()`	Drop every staged object of this run.
`final static Long`	`cleanupAbandoned(ObjectStore store, String finalPrefix, Duration olderThan, Clock clock)`	Delete abandoned staging runs under finalPrefix: any `.staging/<runId>/` whose NEWEST object is older than olderThan.

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

- Constructor Detail
  - StagingArea
```
StagingArea(ObjectStore store, String finalPrefix, String runId, Clock clock)
```
- Method Detail
  - getStagingPrefix
```
 final String getStagingPrefix()
```
  - getFinalPrefix
```
 final String getFinalPrefix()
```
  - getRunId
```
 final String getRunId()
```
  - stageKey
```
 final ObjectKey stageKey(String name)
```
    The staging key for a run-relative artifact name.
  - stage
```
 final PutResult stage(String name, ContentSource source, PutOptions options)
```
    Write one artifact into staging (delegates to ObjectStore.put).
  - stagedObjects
```
 final List<ObjectSummary> stagedObjects()
```
    Everything currently staged for THIS run.
  - publish
```
 final PutResult publish(Map<ObjectKey, ObjectKey> plan, ObjectKey manifestKey, ContentSource manifestBody, PutOptions manifestOptions)
```
    Commit: copy each staged object to its final key per plan, then create manifestKey conditionally, then drop staging. On a lost commit race the already-copied final objects of THIS run are deleted and the PreconditionFailedException is rethrown — the winner's dataset is untouched. plan final keys MUST be run-unique (e.g. carry runId); that is what makes step 2 collision-free without conditional copies.
  - discard
```
 final Long discard()
```
    Drop every staged object of this run. Returns deleted count.
  - cleanupAbandoned
```
 final static Long cleanupAbandoned(ObjectStore store, String finalPrefix, Duration olderThan, Clock clock)
```
    Delete abandoned staging runs under finalPrefix: any .staging/<runId>/ whose NEWEST object is older than olderThan. Returns the number of objects deleted. Safe to run concurrently with live writers as long as their threshold exceeds the writer's maximum quiet period — the rule is deterministic, pick it deliberately.

Class StagingArea

Nested Class Summary

Field Summary

Constructor Summary

Enum Constant Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

StagingArea

Method Detail

getStagingPrefix

getFinalPrefix

getRunId

stageKey

stage

stagedObjects

publish

discard

cleanupAbandoned