Package com.google.gerrit.server.permissions

Class PermissionBackendCondition

java.lang.Object

com.google.gerrit.extensions.conditions.BooleanCondition

com.google.gerrit.extensions.conditions.PrivateInternals_BooleanCondition.SubclassOnlyInCoreServer

com.google.gerrit.server.permissions.PermissionBackendCondition

Direct Known Subclasses:

PermissionBackendCondition.ForChange, PermissionBackendCondition.ForProject, PermissionBackendCondition.ForRef, PermissionBackendCondition.WithUser

public abstract class PermissionBackendCondition
extends PrivateInternals_BooleanCondition.SubclassOnlyInCoreServer

BooleanCondition to evaluate a permission.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PermissionBackendCondition.ForChange
static class	PermissionBackendCondition.ForProject
static class	PermissionBackendCondition.ForRef
static class	PermissionBackendCondition.WithUser

Field Summary

Fields inherited from class com.google.gerrit.extensions.conditions.BooleanCondition

FALSE, TRUE

Constructor Summary

Constructors

Constructor	Description
PermissionBackendCondition()

Method Summary

Modifier and Type	Method	Description
boolean	evaluatesTrivially()	Check if the condition evaluates to either true or false without providing additional information to the evaluation tree, e.g.
BooleanCondition	reduce()	Reduce evaluation tree by cutting off branches that evaluate trivially and replacing them with a leave note corresponding to the value the branch evaluated to.
void	set(boolean val)	Assign a specific testOrFalse result to this condition.
abstract String	toString()

Methods inherited from class com.google.gerrit.extensions.conditions.PrivateInternals_BooleanCondition.SubclassOnlyInCoreServer

children

Methods inherited from class com.google.gerrit.extensions.conditions.BooleanCondition

and, and, not, or, or, value, valueOf

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

PermissionBackendCondition

public PermissionBackendCondition()

Method Detail

set

public void set(boolean val)

Assign a specific testOrFalse result to this condition.

By setting the condition to a specific value the condition will bypass calling PermissionBackend during value(), and immediately return the set value instead.

Parameters:

val - value to return from value().

toString

public abstract String toString()

Overrides:

toString in class Object

evaluatesTrivially

public boolean evaluatesTrivially()

Description copied from class: BooleanCondition

Check if the condition evaluates to either true or false without providing additional information to the evaluation tree, e.g. through checks to a remote service such as PermissionBackend.

In this case, the tree can be reduced to skip all non-trivial checks resulting in a performance gain.

Specified by:

evaluatesTrivially in class BooleanCondition

reduce

public BooleanCondition reduce()

Description copied from class: BooleanCondition

Reduce evaluation tree by cutting off branches that evaluate trivially and replacing them with a leave note corresponding to the value the branch evaluated to.

 Example 1 (T=True, F=False, C=non-trivial check):
      OR
     /  \    =>    T
    C   T
 Example 2 (cuts off a not-trivial check):
      AND
     /  \    =>    F
    C   F
 Example 3:
      AND
     /  \    =>    F
    T   F
 

There is no guarantee that the resulting tree is minimal. The only guarantee made is that branches that evaluate trivially will be cut off and replaced by primitive values.

Specified by:

reduce in class BooleanCondition