FlushClearCache (EclipseLink Core 3.0.4-RC1 API)

java.lang.Object
- org.eclipse.persistence.config.FlushClearCache

```
public class FlushClearCache
extends Object
```
FlushClearCache persistence property defines modes of cache handling after em.flush call followed by em.clear call. This property could be specified while creating either EntityManagerFactory (createEntityManagerFactory or persistence.xml) or EntityManager (createEntityManager); the latter overrides the former.
JPA persistence property Usage:
properties.add(PersistenceUnitProperties.FLUSH_CLEAR_CACHE, FlushClearCache.Drop);
Values are case-insensitive. "" could be used instead of default value FlushClearCache.DEFAULT.

Field Summary

Fields
Modifier and Type	Field	Description
`static String`	`DEFAULT`
`static String`	`Drop`	Call to clear method causes to drop the whole EntityManager cache.
`static String`	`DropInvalidate`	Call to clear method causes to drops the whole EntityManager cache, on commit the classes that have at least one object updated or deleted are invalidated in the shared cache.
`static String`	`Merge`	Call to clear method causes to drop from EntityManager cache only the objects that haven't been flushed.

Constructor Summary

Constructors
Constructor Description

FlushClearCache()

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

- Field Detail
  - Merge
```
public static final String Merge
```
    Call to clear method causes to drop from EntityManager cache only the objects that haven't been flushed. This is the most accurate mode: shared cache is perfect after commit; but the least memory effective: smbd repeatedly using flush followed by clear may eventually run out of memory in a huge transaction.
    
    See Also:
    
    Constant Field Values
  - Drop
```
public static final String Drop
```
    Call to clear method causes to drop the whole EntityManager cache. This is the fasteset and using the least memory mode - but after commit the shared cache potentially contains stale data.
    
    See Also:
    
    Constant Field Values
  - DropInvalidate
```
public static final String DropInvalidate
```
    Call to clear method causes to drops the whole EntityManager cache, on commit the classes that have at least one object updated or deleted are invalidated in the shared cache. This is a compromise mode: potentially a bit slower than drop, but has virtually the same memory efficiency. After commit all potentially stale data is invalidated in the shared cache.
    
    See Also:
    
    Constant Field Values
  - DEFAULT
```
public static final String DEFAULT
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - FlushClearCache
```
public FlushClearCache()
```