org.qtitools.qti.node.expression.general
Class MapResponse

java.lang.Object
  org.qtitools.qti.node.AbstractNode
      org.qtitools.qti.node.AbstractObject
          org.qtitools.qti.node.expression.AbstractExpression
              org.qtitools.qti.node.expression.general.MapResponse

All Implemented Interfaces:

java.io.Serializable, Expression, ExpressionParent, XmlNode, XmlObject, Validatable

public class MapResponse
extends AbstractExpression

This expression looks up the value of A response variable and then transforms it using the associated mapping, which must have been declared. The result is A single float. If the response variable has single cardinality then the value returned is simply the mapped target value from the map. If the response variable has multiple or ordered cardinality then the value returned is the sum of the mapped target values. This expression cannot be applied to variables of record cardinality.

For example, if A mapping associates the identifiers {A,B,C,D} with the values {0,1,0.5,0} respectively then mapResponse will map the single value 'C' to the numeric value 0.5 and the set of values {C,B} to the value 1.5.

If A container contains multiple instances of the same value then that value is counted once only. To continue the example above {B,B,C} would still map to 1.5 and not 2.5.

Author:

Jiri Kajaba, Jonathon Hare

See Also:

Serialized Form

Field Summary

static java.lang.String	ATTR_IDENTIFIER_NAME Name of identifier attribute in xml schema.
static java.lang.String	CLASS_TAG Name of this class in xml schema.

Fields inherited from class org.qtitools.qti.node.expression.AbstractExpression

logger

Fields inherited from interface org.qtitools.qti.node.expression.Expression

DISPLAY_NAME

Fields inherited from interface org.qtitools.qti.node.XmlNode

INDENT, NEW_LINE, SIMPLE_NAME_INNER_SEPARATOR, SIMPLE_NAMES_SEPARATOR

Constructor Summary

MapResponse(ExpressionParent parent)
Constructs expression.

Method Summary

protected Value	evaluateSelf(int depth) Evaluates this expression.
java.lang.String	getClassTag() Gets QTI class name of this node.
java.lang.String	getIdentifier() Gets value of identifier attribute.
boolean	isVariable() Returns true if value of evaluation can change every evaluation call; false otherwise.
void	setIdentifier(java.lang.String identifier) Sets new value of identifier attribute.
ValidationResult	validate() Validates this object.

Methods inherited from class org.qtitools.qti.node.expression.AbstractExpression

evaluate, getBaseType, getCardinality, getChildren, getFirstChild, getParent, getParentRequiredBaseTypes, getParentRequiredCardinalities, getProducedBaseTypes, getProducedCardinalities, getProducedNumericalBaseTypes, getRequiredBaseTypes, getRequiredCardinalities, getRequiredSameBaseTypes, getRequiredSameCardinalities, getSecondChild, getType, getValue, isAnyChildNull, isNull, reset, toString

Methods inherited from class org.qtitools.qti.node.AbstractObject

getParentItem, getParentResult, getParentTest, setParent

Methods inherited from class org.qtitools.qti.node.AbstractNode

attrToXmlString, bodyToXmlString, getAttributes, getFullName, getIndent, getNode, getNode, getNode, getNodeGroups, getParentRoot, getSimpleName, getSourceFile, getSourceNode, getSourceString, getSourceUrl, hasChildNodes, load, load, load, load, loadAttributes, readChild, readChildren, setParent, setSourceFile, setSourceNode, setSourceString, setSourceUrl, toXmlString, toXmlString, validateAttributes, validateChildren

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.qtitools.qti.node.XmlObject

getParentItem, getParentResult, getParentTest, setParent

Methods inherited from interface org.qtitools.qti.node.XmlNode

getAttributes, getFullName, getNodeGroups, getParentRoot, getSimpleName, getSourceFile, getSourceNode, getSourceString, getSourceUrl, hasChildNodes, load, load, load, load, setSourceFile, setSourceNode, setSourceString, setSourceUrl, toXmlString, toXmlString

Field Detail

CLASS_TAG

public static final java.lang.String CLASS_TAG

Name of this class in xml schema.

See Also:

Constant Field Values

ATTR_IDENTIFIER_NAME

public static final java.lang.String ATTR_IDENTIFIER_NAME

Name of identifier attribute in xml schema.

See Also:

Constant Field Values

Constructor Detail

MapResponse

public MapResponse(ExpressionParent parent)

Constructs expression.

Parameters:

parent - parent of this expression

Method Detail

getClassTag

public java.lang.String getClassTag()

Description copied from interface: XmlNode

Gets QTI class name of this node.

QTI class name has very important role during loading/saving nodes.

For example: Java class name is AssessmentTest; QTI class name is assessmentTest.

Specified by:

getClassTag in interface XmlNode

Specified by:

getClassTag in class AbstractNode

Returns:

QTI class name of this node

getIdentifier

public java.lang.String getIdentifier()

Gets value of identifier attribute.

Returns:

value of identifier attribute

See Also:

setIdentifier(java.lang.String)

setIdentifier

public void setIdentifier(java.lang.String identifier)

Sets new value of identifier attribute.

Parameters:

identifier - new value of identifier attribute

See Also:

getIdentifier()

validate

public ValidationResult validate()

Description copied from interface: Validatable

Validates this object.

Specified by:

validate in interface Validatable

Overrides:

validate in class AbstractExpression

Returns:

validation result

evaluateSelf

protected Value evaluateSelf(int depth)

Description copied from class: AbstractExpression

Evaluates this expression. All children must be already evaluated. Contains no checks.

Specified by:

evaluateSelf in class AbstractExpression

Parameters:

depth - depth of this expression in expression tree (root's depth = 0)

Returns:

result of evaluation

isVariable

public boolean isVariable()

Description copied from interface: Expression

Returns true if value of evaluation can change every evaluation call; false otherwise. It checks this expression and all of its children (if any child is variable, this expression becomes variable too). Example of variable expressions: variable and outcome expressions.

Specified by:

isVariable in interface Expression

Overrides:

isVariable in class AbstractExpression

Returns:

true if value of evaluation can change every evaluation call; false otherwise