Package org.apache.hadoop.yarn.util.constraint

Class PlacementConstraintParser

java.lang.Object

org.apache.hadoop.yarn.util.constraint.PlacementConstraintParser

@Public
@Unstable
public final class PlacementConstraintParser
extends Object

Placement constraint expression parser.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PlacementConstraintParser.BaseStringTokenizer	A basic tokenizer that splits an expression by a given delimiter.
static class	PlacementConstraintParser.CardinalityConstraintParser	Constraint parser used to parse a given target expression, such as "cardinality, NODE, foo, 0, 1".
static class	PlacementConstraintParser.ConjunctionConstraintParser	Parser used to parse conjunction form of constraints, such as AND(A, ..., B), OR(A, ..., B).
static final class	PlacementConstraintParser.ConjunctionTokenizer	Tokenizer used to parse conjunction form of a constraint expression, [AND|OR](C1:C2:...
static class	PlacementConstraintParser.ConstraintParser	Constraint Parser used to parse placement constraints from a given expression.
static interface	PlacementConstraintParser.ConstraintTokenizer	Tokenizer interface that used to parse an expression.
static class	PlacementConstraintParser.MultipleConstraintsTokenizer	Tokenizer used to handle a placement spec composed by multiple constraint expressions.
static class	PlacementConstraintParser.NodeConstraintParser	Constraint parser used to parse a given target expression.
static final class	PlacementConstraintParser.SourceTags	A helper class to encapsulate source tags and allocations in the placement specification.
static class	PlacementConstraintParser.SourceTagsTokenizer	Tokenizer used to parse allocation tags expression, which should be in tag(numOfAllocations) syntax.
static class	PlacementConstraintParser.TargetConstraintParser	Constraint parser used to parse a given target expression, such as "NOTIN, NODE, foo, bar".

Field Summary

Fields

Modifier and Type	Field	Description
static final char	EXPRESSION_VAL_DELIM

Method Summary

Modifier and Type	Method	Description
static PlacementConstraint.AbstractConstraint	parseExpression(String constraintStr)	Parses a given constraint expression to a PlacementConstraint.AbstractConstraint, this expression can be any valid form of constraint expressions.
static Map<PlacementConstraintParser.SourceTags,PlacementConstraint>	parsePlacementSpec(String expression)	Parses a placement constraint specification.

Methods inherited from class java.lang.Object

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

Field Details

EXPRESSION_VAL_DELIM

public static final char EXPRESSION_VAL_DELIM

See Also:

• Constant Field Values

Method Details

parseExpression

public static PlacementConstraint.AbstractConstraint parseExpression(String constraintStr)
                                                              throws PlacementConstraintParseException

Parses a given constraint expression to a PlacementConstraint.AbstractConstraint, this expression can be any valid form of constraint expressions.

Parameters:

constraintStr - expression string

Returns:

a parsed PlacementConstraint.AbstractConstraint

Throws:

PlacementConstraintParseException - when given expression is malformed

parsePlacementSpec

public static Map<PlacementConstraintParser.SourceTags,PlacementConstraint> parsePlacementSpec(String expression)
                                                                                        throws PlacementConstraintParseException

Parses a placement constraint specification. A placement constraint spec is a composite expression which is composed by multiple sub constraint expressions delimited by ":". With following syntax:

Tag1(N1),P1:Tag2(N2),P2:...:TagN(Nn),Pn

where TagN(Nn) is a key value pair to determine the source allocation tag and the number of allocations, such as:

foo(3)

Optional when using NodeAttribute Constraint. and where Pn can be any form of a valid constraint expression, such as:

• in,node,foo,bar
• notin,node,foo,bar,1,2
• and(notin,node,foo:notin,node,bar)

and NodeAttribute Constraint such as

• yarn.rm.io/foo=true
• java=1.7,1.8

Parameters:

expression - expression string.

Returns:

a map of source tags to placement constraint mapping.

Throws:

PlacementConstraintParseException - when the placement constraint parser fails to parse an expression.