SequencingControl (EclipseLink 2.6.6, API Reference)

```
public interface SequencingControl
```
Purpose: Define an interface to control sequencing functionality.
Description: This interface is accessed through DatabaseSession.getSequencingControl(). It allows to create, re-create, customize Sequencing object which is available through DatabaseSession.getSequencing() and provides sequencing values for all descriptors that use sequencing. Here's the lifecycle of Sequencing object used by DatabaseSession: 1. DatabaseSession created - sequencing object doesn't yet exist; 2. DatabaseSession.login() causes creation of Sequencing object; 3. DatabaseSession.logout() causes destruction of Sequencing object. In case sequencing object doesn't yet exist all the set parameters' values will be used during its creation. In case sequencing object already exists: 1. The following methods don't alter sequencing object - the corresponding parameters will only be used in case a new sequencing object is created: setShouldUseSeparateConnection; setLogin; setMinPoolSize; setMaxPoolSize. 2. The following methods cause immediate destruction of the sequencing object and creation of a new one: setValueGenerationPolicy; setShouldUseNativeSequencing; setShouldUseTableSequencing; resetSequencing; 3. The following methods cause change immediately: setPreallocationSize (next sequencing preallocation will use the set parameter's value).
Responsibilities:
- Define the APIs for controlling sequencing.
See Also:
Sequence, DatabaseSession

Method Summary

Methods
Modifier and Type	Method and Description
`ConnectionPool`	`getConnectionPool()` ADVANCED: Return the connection pool to use for sequencing.
`Login`	`getLogin()` ADVANCED: Return a DatabaseLogin to be used by separate sequencing connection(s).
`int`	`getMaxPoolSize()` PUBLIC: Returns a maximum number of connections in sequencing connection pool
`int`	`getMinPoolSize()` PUBLIC: Returns a minimum number of connections in sequencing connection pool.
`void`	`initializePreallocated()` ADVANCED: Removes all preallocated sequencing objects.
`void`	`initializePreallocated(java.lang.String seqName)` ADVANCED: Removes all preallocated sequencing objects for the given sequence name.
`boolean`	`isConnectedUsingSeparateConnection()` PUBLIC: Indicates whether sequencing actually uses separate connection(s).
`void`	`resetSequencing()` ADVANCED: Immediately re-create sequencing object.
`void`	`setConnectionPool(ConnectionPool pool)` ADVANCED: Set the connection pool to use for sequencing.
`void`	`setInitialPoolSize(int size)` PUBLIC: Sets a initial number of connections in sequencing connection pool The set value is ignored if shouldUseSeparateConnection() returns false.
`void`	`setLogin(Login login)` ADVANCED: Returns a DatabaseLogin to be used by separate sequencing connection(s) The set value is ignored if shouldUseSeparateConnection() returns false.
`void`	`setMaxPoolSize(int size)` PUBLIC: Sets a maximum number of connections in sequencing connection pool The set value is ignored if shouldUseSeparateConnection() returns false.
`void`	`setMinPoolSize(int size)` PUBLIC: Sets a minimum number of connections in sequencing connection pool The set value is ignored if shouldUseSeparateConnection() returns false.
`void`	`setShouldUseSeparateConnection(boolean shouldUseSeparateConnection)` PUBLIC: Set whether separate connection(s) for sequencing could be used (by default it couldn't).
`boolean`	`shouldUseSeparateConnection()` PUBLIC: Indicate whether separate connection(s) for sequencing could be used (by default it couldn't).

- Method Detail
  - resetSequencing
```
void resetSequencing()
```
    ADVANCED: Immediately re-create sequencing object. The only reason to use this method is to pick up all parameters' values that were changed after the original sequencing object has been created.
  - shouldUseSeparateConnection
```
boolean shouldUseSeparateConnection()
```
    PUBLIC: Indicate whether separate connection(s) for sequencing could be used (by default it couldn't). If this flag is set to true then separate connection(s) for sequencing will be used in case getSequence().shouldUseSeparateConnection() returns true.
    
    See Also:
    Sequence
  - setShouldUseSeparateConnection
```
void setShouldUseSeparateConnection(boolean shouldUseSeparateConnection)
```
    PUBLIC: Set whether separate connection(s) for sequencing could be used (by default it couldn't). If this flag is set to true then separate connection(s) for sequencing will be used in case getSequence().shouldUseSeparateConnection() returns true.
    
    See Also:
    Sequence
  - isConnectedUsingSeparateConnection
```
boolean isConnectedUsingSeparateConnection()
```
    PUBLIC: Indicates whether sequencing actually uses separate connection(s). Returns true if sequencing is connected and uses separate connection(s). Returns false if sequencing is not connected (getSequencing()==null). Note that if shouldUseSeparateConnection() returns false this method also returns false. However if shouldUseSeparateConnection() returns true this method returns false in the following two cases:
    sequencing is not connected;
    getSequence().shouldUseSeparateConnection() == false.
    
    See Also:
    Sequence
  - getLogin
```
Login getLogin()
```
    ADVANCED: Return a DatabaseLogin to be used by separate sequencing connection(s).
    
    See Also:
    DatabaseLogin
  - setLogin
```
void setLogin(Login login)
```
    ADVANCED: Returns a DatabaseLogin to be used by separate sequencing connection(s) The set value is ignored if shouldUseSeparateConnection() returns false. The DatabaseLogin *MUST*: 1. specify *NON-JTS* connections (such as NON_JTS driver or read-only datasource); 2. sequenceLogin.shouldUseExternalTransactionController()==false In case this method is not called, but separate connection should be used, sequencing will use a clone of login owned by the DatabaseSession, or a clone of read login owned by ServerSession.
    
    See Also:
    DatabaseLogin
  - getConnectionPool
```
ConnectionPool getConnectionPool()
```
    ADVANCED: Return the connection pool to use for sequencing.
  - setConnectionPool
```
void setConnectionPool(ConnectionPool pool)
```
    ADVANCED: Set the connection pool to use for sequencing.
  - getMinPoolSize
```
int getMinPoolSize()
```
    PUBLIC: Returns a minimum number of connections in sequencing connection pool.
    
    See Also:
    ConnectionPool, ServerSession
  - setMinPoolSize
```
void setMinPoolSize(int size)
```
    PUBLIC: Sets a minimum number of connections in sequencing connection pool The set value is ignored if shouldUseSeparateConnection() returns false. The set value is ignored if SequencingControl has been obtained not from ServerSession. By default is 2.
    
    See Also:
    ConnectionPool, ServerSession
  - getMaxPoolSize
```
int getMaxPoolSize()
```
    PUBLIC: Returns a maximum number of connections in sequencing connection pool
    
    See Also:
    ConnectionPool, ServerSession
  - setMaxPoolSize
```
void setMaxPoolSize(int size)
```
    PUBLIC: Sets a maximum number of connections in sequencing connection pool The set value is ignored if shouldUseSeparateConnection() returns false. The set value is ignored if SequencingControl has been obtained not from ServerSession. By default is 2.
    
    See Also:
    ConnectionPool, ServerSession
  - setInitialPoolSize
```
void setInitialPoolSize(int size)
```
    PUBLIC: Sets a initial number of connections in sequencing connection pool The set value is ignored if shouldUseSeparateConnection() returns false. The set value is ignored if SequencingControl has been obtained not from ServerSession. By default is 1.
    
    See Also:
    ConnectionPool, ServerSession
  - initializePreallocated
```
void initializePreallocated()
```
    ADVANCED: Removes all preallocated sequencing objects. Ignored if getSequencingValueGenarationPolicy().shouldUsePreallocation() returns false. This method is called internally after Sequencing object is destructed.
    
    See Also:
    Sequence
  - initializePreallocated
```
void initializePreallocated(java.lang.String seqName)
```
    ADVANCED: Removes all preallocated sequencing objects for the given sequence name. Ignored if getSequencingValueGenarationPolicy().shouldUsePreallocation() returns false.
    
    See Also:
    Sequence

Interface SequencingControl

Method Summary

Method Detail

resetSequencing

shouldUseSeparateConnection

setShouldUseSeparateConnection

isConnectedUsingSeparateConnection

getLogin

setLogin

getConnectionPool

setConnectionPool

getMinPoolSize

setMinPoolSize

getMaxPoolSize

setMaxPoolSize

setInitialPoolSize

initializePreallocated

initializePreallocated