Package com.yahoo.searchlib.rankingexpression.evaluation

Class MapContext

java.lang.Object

com.yahoo.searchlib.rankingexpression.evaluation.Context

com.yahoo.searchlib.rankingexpression.evaluation.MapContext

All Implemented Interfaces:

com.yahoo.tensor.evaluation.EvaluationContext<Reference>, com.yahoo.tensor.evaluation.TypeContext<Reference>

public class MapContext
extends Context

A context backed by a Map

Author:

bratseth

Constructor Summary

Constructors

Constructor	Description
MapContext()
MapContext(Value missingValue)
MapContext(Map<String,Value> bindings)
MapContext(Map<String,Value> bindings, Value missingValue)	Creates a map context from a map.

Method Summary

Modifier and Type	Method	Description
Map<String,Value>	bindings()	Returns an immutable view of the bindings of this.
MapContext	freeze()	Freezes this.
static MapContext	fromString(String contextString)	A convenience constructor which returns a map context from a string on the form name1:value1, name2:value2 ....
Value	get(String key)	Returns the value of a key.
com.yahoo.tensor.TensorType	getType(Reference key)	Returns the type of the given value key, or null if it is not bound.
Set<String>	names()	Returns an unmodifiable map of the names of this
void	put(String key, Value value)	Sets the value of a key.
MapContext	thawedCopy()	Returns a new, modifiable context containing all the bindings of this
String	toString()

Methods inherited from class com.yahoo.searchlib.rankingexpression.evaluation.Context

get, get, getDouble, getTensor, getType, put

Methods inherited from class java.lang.Object

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

Constructor Detail

MapContext

public MapContext()

MapContext

public MapContext(Value missingValue)

MapContext

public MapContext(Map<String,Value> bindings)

MapContext

public MapContext(Map<String,Value> bindings,
                  Value missingValue)

Creates a map context from a map. All the Values of the map will be frozen.

Method Detail

freeze

public MapContext freeze()

Freezes this. Returns this for convenience.

getType

public com.yahoo.tensor.TensorType getType(Reference key)

Returns the type of the given value key, or null if it is not bound.

get

public Value get(String key)

Returns the value of a key. 0 is returned if the given key is not bound in this.

Specified by:

get in class Context

Parameters:

key - the name of the variable whose value to return.

Returns:

the value of the named variable.

put

public void put(String key,
                Value value)

Sets the value of a key. The value is frozen by this.

Overrides:

put in class Context

Parameters:

key - the name of the variable to set.

value - the value to set. Ownership of this value is transferred to this - if it is mutable (not frozen) it may be modified during execution

bindings

public Map<String,Value> bindings()

Returns an immutable view of the bindings of this.

thawedCopy

public MapContext thawedCopy()

Returns a new, modifiable context containing all the bindings of this

names

public Set<String> names()

Returns an unmodifiable map of the names of this

Overrides:

names in class Context

Returns:

the set of all variable names.

toString

public String toString()

Overrides:

toString in class Object

fromString

public static MapContext fromString(String contextString)

A convenience constructor which returns a map context from a string on the form name1:value1, name2:value2 .... Extra spaces are allowed anywhere. Any other deviation from the syntax causes an exception to be thrown.