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

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.LookupExpression

All Implemented Interfaces:

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

Direct Known Subclasses:

Correct, Default, Variable

public abstract class LookupExpression
extends AbstractExpression

Parent of correct, default and variable expression.

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	IDENTIFIER_SEPARATOR Separator between two parts of compound identifier.

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

LookupExpression(ExpressionParent parent)
Constructs expression.

Method Summary

protected java.lang.String	getFirstPart() Gets first part of compound identifier or whole identifier if identifier is not compound.
java.lang.String	getIdentifier() Gets value of identifier attribute.
BaseType[]	getProducedBaseTypes() Gets list of all possible produced baseTypes after evaluation (possible baseTypes of evaluated result).
Cardinality[]	getProducedCardinalities() Gets list of all possible produced cardinalities after evaluation (possible cardinalities of evaluated result).
protected java.lang.String	getSecondPart() Gets second part of compound identifier or null if identifier is not compound.
protected boolean	hasMoreParts() Returns true if identifier is compound from two parts separated with dot; false otherwise.
protected boolean	isValid(ValidationResult result) Returns true if identifier is valid; false otherwise.
boolean	isVariable() Returns true if value of evaluation can change every evaluation call; false otherwise.
protected VariableDeclaration	lookupDeclaration()
protected VariableDeclaration	lookupDeclaration(AssessmentItem item, java.lang.String identifier) Looks up for variable declaration.
void	setIdentifier(java.lang.String identifier) Sets new value of identifier attribute.

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

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

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

Field Detail

ATTR_IDENTIFIER_NAME

public static final java.lang.String ATTR_IDENTIFIER_NAME

Name of identifier attribute in xml schema.

See Also:

Constant Field Values

IDENTIFIER_SEPARATOR

public static final java.lang.String IDENTIFIER_SEPARATOR

Separator between two parts of compound identifier.

See Also:

Constant Field Values

Constructor Detail

LookupExpression

public LookupExpression(ExpressionParent parent)

Constructs expression.

Parameters:

parent - parent of this expression

Method Detail

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()

hasMoreParts

protected boolean hasMoreParts()

Returns true if identifier is compound from two parts separated with dot; false otherwise.

Returns:

true if identifier is compound from two parts separated with dot; false otherwise

getFirstPart

protected java.lang.String getFirstPart()

Gets first part of compound identifier or whole identifier if identifier is not compound.

Returns:

first part of compound identifier or whole identifier if identifier is not compound

getSecondPart

protected java.lang.String getSecondPart()

Gets second part of compound identifier or null if identifier is not compound.

Returns:

second part of compound identifier or null if identifier is not compound

isValid

protected boolean isValid(ValidationResult result)

Returns true if identifier is valid; false otherwise.

This method checks:

• if identifier is defined (not null)
• if identifier does not contain more than one dot
• if all parts of identifier are valid identifier baseType

Parameters:

result - validation result where to store eventual validation messages

Returns:

true if identifier is valid; false otherwise

lookupDeclaration

protected VariableDeclaration lookupDeclaration(AssessmentItem item,
                                                java.lang.String identifier)

Looks up for variable declaration.

Parameters:

item - where to look up

identifier - identifier of requested variable declaration

Returns:

variable declaration with given identifier or null

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

lookupDeclaration

protected VariableDeclaration lookupDeclaration()

getProducedBaseTypes

public BaseType[] getProducedBaseTypes()

Description copied from interface: Expression

Gets list of all possible produced baseTypes after evaluation (possible baseTypes of evaluated result). Result of this method can change in time.

Static example is expression or. Expression or can produce only boolean baseType and it cannot change.

Dynamic example is expression variable. Expression variable can produce any baseType before evaluation. After evaluation it produces baseType of its result (and it can change every evaluation call!).

Null expression, empty containers (multiple, ordered, record), or NULL values produces all baseTypes. So they are compatible with anything.

Specified by:

getProducedBaseTypes in interface Expression

Overrides:

getProducedBaseTypes in class AbstractExpression

Returns:

list of all possible produced baseTypes after evaluation

getProducedCardinalities

public Cardinality[] getProducedCardinalities()

Description copied from interface: Expression

Gets list of all possible produced cardinalities after evaluation (possible cardinalities of evaluated result). Result of this method can change in time.

Static example is expression or. Expression or can produce only single cardinality and it cannot change.

Dynamic example is expression variable. Expression variable can produce any cardinality before evaluation. After evaluation it produces cardinality of its result (and it can change every evaluation call!).

Null expression, empty containers (multiple, ordered, record), or NULL values produces all cardinalities. So they are compatible with anything.

Specified by:

getProducedCardinalities in interface Expression

Overrides:

getProducedCardinalities in class AbstractExpression

Returns:

list of all possible produced cardinalities after evaluation