SequenceService (Imixs Office Workflow Util 4.6.0 API)

java.lang.Object
- org.imixs.workflow.office.util.SequenceService

```
@DeclareRoles({"org.imixs.ACCESSLEVEL.NOACCESS","org.imixs.ACCESSLEVEL.READERACCESS","org.imixs.ACCESSLEVEL.AUTHORACCESS","org.imixs.ACCESSLEVEL.EDITORACCESS","org.imixs.ACCESSLEVEL.MANAGERACCESS"})
@RolesAllowed({"org.imixs.ACCESSLEVEL.NOACCESS","org.imixs.ACCESSLEVEL.READERACCESS","org.imixs.ACCESSLEVEL.AUTHORACCESS","org.imixs.ACCESSLEVEL.EDITORACCESS","org.imixs.ACCESSLEVEL.MANAGERACCESS"})
@RunAs("org.imixs.ACCESSLEVEL.MANAGERACCESS")
public class SequenceService
extends Object
```
The SequcneceService is a singleton EJB which handles continuous sequenceNumbers for a workitem separated for each workflowGroup.
The sequence numbers are stored in the item 'sequencenumbers' of the configuration entity with the name "BASIC" in in the following format
[GROUP]=123
Optimistic Locking Problem
In earlier versions, the method runs in a OptimisticLockException in case that multiple processes run in parallel. To fix this the service is changed into a singleton. See issue #290.

Author:

rsoika

Nested Class Summary

Nested Classes
Modifier and Type Class Description

class SequenceService.SequenceNumber
A SequenceNumber is a internal object separating a fixed part form a number part.

Field Summary

Fields
Modifier and Type Field Description

static String ITEM_SEQUENCENUMBER

static String ITEM_SEQUENCENUMBER_DEPRECATED

Constructor Summary

Constructors
Constructor Description

SequenceService()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`computeSequenceNumber(org.imixs.workflow.ItemCollection documentContext)`	This method computes the sequence number based on a configuration entity with the name "BASIC".
`boolean`	`hasSequenceNumber(org.imixs.workflow.ItemCollection documentContext)`	This method verifies if a sequence number already exists.

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

- Field Detail
  - ITEM_SEQUENCENUMBER
```
public static final String ITEM_SEQUENCENUMBER
```
    See Also:
    
    Constant Field Values
  - ITEM_SEQUENCENUMBER_DEPRECATED
```
public static final String ITEM_SEQUENCENUMBER_DEPRECATED
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - SequenceService
```
public SequenceService()
```
- Method Detail
  - computeSequenceNumber
```
public void computeSequenceNumber(org.imixs.workflow.ItemCollection documentContext)
                           throws org.imixs.workflow.exceptions.AccessDeniedException
```
    This method computes the sequence number based on a configuration entity with the name "BASIC". The configuration provides a property 'sequencenumbers' with the current number range for each workflowGroup. If a Workitem have a WorkflowGroup with no corresponding entry the method will not compute a new number.
    This method loads and updates the configuration entity in a new transaction. In combination with the
    
    Throws:
    
    InvalidWorkitemException
    
    org.imixs.workflow.exceptions.AccessDeniedException
  - hasSequenceNumber
```
public boolean hasSequenceNumber(org.imixs.workflow.ItemCollection documentContext)
```
    This method verifies if a sequence number already exists.
    The method also migrate the old item name 'numsequencenumber' into the new item name 'sequencenumber'
    
    Parameters:
    
    documentContext -