org.camunda.bpm.engine.authorization

Interface Permission

All Known Implementing Classes:

BatchPermissions, OptimizePermissions, Permissions, ProcessDefinitionPermissions, ProcessInstancePermissions, TaskPermissions, UserOperationLogCategoryPermissions

public interface Permission

A permission represents an authorization to interact with a given resource in a specific way. See Permissions for a set of built-in permissions and Authorization for general overview on authorizations.

In camunda BPM, multiple permissions are grouped into an Authorization. For efficient storage and checking of authorizations, the permissons that make up an authorization are coded into a single integer. The implication of this design is that a permission must have a unique integer value and it must be a power of two, ie 2^0, 2^1, 2^2, 2^3, 2^4 ... The permission can then be added to an authorization using bitwise OR:

        Auth: 0000001001001
 Perm to add: 0000000010000 
 bit OR (|) : 0000001011001 
 

and removed using bitwise AND of the inverted value:

        Auth: 0000001001001
 Perm to rem: 0000000001000 
 invert (~) : 1111111110111
 bit AND (&): 0000001000001    
 

Defining a custom Permission

The XxxPermissions classes contains the values of the built-in permissions (i.e. Permissions, ProcessDefinitionPermissions, ProcessInstancePermissions, TaskPermissions, all can be found in authorization package). In order to define a custom permission, you must provide an implementation of this interface such that the getValue() method returns an integer which is a power of two and not yet used by any of the built-in Permissions. Keep the Permission's names unique as well. You must implement also getTypes() and make sure that the permission values are not already reserved for the desired Resource.

Since:

7.0

Author:

Daniel Meyer

Method Summary

Modifier and Type	Method and Description
String	getName() returns the name of the permission, ie.
Resource[]	getTypes() returns the resource types which are allowed for this permission
int	getValue() returns the unique numeric value of the permission.

Method Detail

getName

String getName()

returns the name of the permission, ie. 'UPDATE'

getValue

int getValue()

returns the unique numeric value of the permission. Must be a power of 2. ie 2^0, 2^1, 2^2, 2^3, 2^4 ...

getTypes

Resource[] getTypes()

returns the resource types which are allowed for this permission