org.opendaylight.yangtools.yang.model.api

Interface PathExpression

All Superinterfaces:

Immutable, MutationBehaviour<Immutable>

All Known Implementing Classes:

AbstractPathExpression, PathExpressionImpl

@Beta
 @NonNullByDefault
public interface PathExpression
extends Immutable

An expression as defined in RFC7950 Section 9.9.2, i.e. the argument of a path statement.

Semantically a PathExpression is similar to a YangXPathExpression with guarantees around what subexpressions it can contain:

• the root expression must be a YangLocationPath
• it can contain steps only along YangXPathAxis.CHILD and YangXPathAxis.PARENT axis
• all steps along YangXPathAxis.CHILD axis are YangLocationPath.QNameStep
• the only function invocation is YangFunction.CURRENT
• only YangBinaryOperator.EQUALS is allowed
• no literals nor numbers are allowed
• all qualified node identifiers must me resolved

Author:

Robert Varga

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	PathExpression.DerefSteps Steps of a PathExpression which is a combination of deref() function call and a relative path, corresponding to Errata 5617.
static class	PathExpression.LocationPathSteps Steps of a PathExpression which is a LocationPath, corresponding to RFC7950 base specification.
static class	PathExpression.Steps Abstract base class for expressing steps of a PathExpression.

Method Summary

Modifier and Type	Method and Description
String	getOriginalString() Returns the path expression formatted string as is defined in model.
PathExpression.Steps	getSteps() Return the path of this expression, which can either be a YangLocationPath (compliant to RFC7950) or a YangPathExpr with filter being an invocation of YangFunction.DEREF.
default boolean	isAbsolute() Returns true if the XPapth starts in root of YANG model, otherwise returns false.

Method Detail

getOriginalString

String getOriginalString()

Returns the path expression formatted string as is defined in model. For example: /prefix:container/prefix:container::cond[when()=foo]/prefix:leaf

Returns:

the path expression formatted string as is defined in model.

getSteps

PathExpression.Steps getSteps()

Return the path of this expression, which can either be a YangLocationPath (compliant to RFC7950) or a YangPathExpr with filter being an invocation of YangFunction.DEREF.

Returns:

The path's steps

Throws:

UnsupportedOperationException - if the implementation has not parsed the string. Implementations are strongly encouraged to perform proper parsing.

isAbsolute

default boolean isAbsolute()

Returns true if the XPapth starts in root of YANG model, otherwise returns false.

Returns:

true if the XPapth starts in root of YANG model, otherwise returns false