Package org.jboss.as.controller.transform

Class DiscardAttributesTransformer

java.lang.Object

org.jboss.as.controller.transform.DiscardAttributesTransformer

All Implemented Interfaces:

OperationTransformer, ResourceTransformer

public abstract class DiscardAttributesTransformer
extends Object
implements OperationTransformer, ResourceTransformer

Discards attributes silently. This class should ONLY be used if you are 100% sure a new attribute can be discarded, even if set. Provide a DiscardAttributesTransformer.DiscardApprover to the constructor to provide specific logic for making the determination as to whether the transformation should be done. It is made abstract to make you think about using it.

Normally, you would want to use DiscardUndefinedAttributesTransformer instead.

A typical use case for this transformer would be in combination with DiscardUndefinedAttributesTransformer. First this transformer would run, with a DiscardAttributesTransformer.DiscardApprover checking the state of the model or operation to decide whether removing attributes is valid. The discard approver would only approve the removal if the value of the model or operation parameters is such that the servers launched by a slave Host Controller running the legacy version and unaware of the removed attributes would function consistently with newer version servers who saw the attributes. This transformer would remove the attributes in that case, and leave them otherwise. Then the DiscardUndefinedAttributesTransformer would run and would log a warning or fail operations if any of the attributes were left. So this transformer cleans if possible, and DiscardUndefinedAttributesTransformer deals with any problems left after cleaning.

Author:

Kabir Khan

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	DiscardAttributesTransformer.AttributeValueDiscardApprover	A DiscardApprover that checks the value of a provided attribute in order to decide whether transformation is allowed.
static interface	DiscardAttributesTransformer.DiscardApprover	Approves the transformation of the resource or operation.

Nested classes/interfaces inherited from interface org.jboss.as.controller.transform.OperationTransformer

OperationTransformer.TransformedOperation

Field Summary

Fields

Modifier and Type	Field	Description
static DiscardAttributesTransformer.DiscardApprover	LENIENT_DISCARD_APPROVER	A DiscardApprover that always returns true; use with extreme caution. It would be a very unusual situation for it to be appropriate to always transform a resource or operation regardless of the values in the model or operation.

Fields inherited from interface org.jboss.as.controller.transform.OperationTransformer

DEFAULT, DEFAULT_REJECTION_POLICY, DISCARD, SUCCESSFUL_RESULT

Fields inherited from interface org.jboss.as.controller.transform.ResourceTransformer

DEFAULT, DISCARD

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	DiscardAttributesTransformer(DiscardAttributesTransformer.DiscardApprover discardApprover, String... attributeNames)	Creates a new transformer.
	DiscardAttributesTransformer(DiscardAttributesTransformer.DiscardApprover discardApprover, Set<String> attributeNames)	Creates a new transformer.
protected	DiscardAttributesTransformer(DiscardAttributesTransformer.DiscardApprover discardApprover, AttributeDefinition... attributes)	Creates a new transformer.

Method Summary

Modifier and Type	Method	Description
OperationTransformer	getUndefineAttributeTransformer()
OperationTransformer	getWriteAttributeTransformer()
OperationTransformer.TransformedOperation	transformOperation(TransformationContext context, PathAddress address, org.jboss.dmr.ModelNode operation)	Transform the operation.
void	transformResource(ResourceTransformationContext context, PathAddress address, Resource resource)	Transform a resource.

Methods inherited from class java.lang.Object

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

Field Detail

LENIENT_DISCARD_APPROVER

public static final DiscardAttributesTransformer.DiscardApprover LENIENT_DISCARD_APPROVER

A DiscardApprover that always returns true; use with extreme caution. It would be a very unusual situation for it to be appropriate to always transform a resource or operation regardless of the values in the model or operation.

Constructor Detail

DiscardAttributesTransformer

protected DiscardAttributesTransformer(DiscardAttributesTransformer.DiscardApprover discardApprover,
                                       AttributeDefinition... attributes)

Creates a new transformer.

Parameters:

discardApprover - approves whether or not transformation should be done. Cannot be null

attributes - the attributes to discard

DiscardAttributesTransformer

protected DiscardAttributesTransformer(DiscardAttributesTransformer.DiscardApprover discardApprover,
                                       String... attributeNames)

Creates a new transformer.

Parameters:

discardApprover - approves whether or not transformation should be done. Cannot be null

attributeNames - the attributes to discard

DiscardAttributesTransformer

public DiscardAttributesTransformer(DiscardAttributesTransformer.DiscardApprover discardApprover,
                                    Set<String> attributeNames)

Creates a new transformer.

Parameters:

discardApprover - approves whether or not transformation should be done. Cannot be null

attributeNames - the attributes to discard

Method Detail

getWriteAttributeTransformer

public OperationTransformer getWriteAttributeTransformer()

getUndefineAttributeTransformer

public OperationTransformer getUndefineAttributeTransformer()

transformOperation

public OperationTransformer.TransformedOperation transformOperation(TransformationContext context,
                                                                    PathAddress address,
                                                                    org.jboss.dmr.ModelNode operation)
                                                             throws OperationFailedException

Description copied from interface: OperationTransformer

Transform the operation.

Specified by:

transformOperation in interface OperationTransformer

Parameters:

context - the operation context

address - the path address

operation - the operation

Returns:

the transformed operation

Throws:

OperationFailedException

transformResource

public void transformResource(ResourceTransformationContext context,
                              PathAddress address,
                              Resource resource)
                       throws OperationFailedException

Description copied from interface: ResourceTransformer

Transform a resource.

Specified by:

transformResource in interface ResourceTransformer

Parameters:

context - the resource transformation context

address - the path address

resource - the resource to transform

Throws:

OperationFailedException