com.xmlmind.xml.xpath

Class VariantBase

java.lang.Object

com.xmlmind.xml.xpath.VariantBase

All Implemented Interfaces:

Variant

Direct Known Subclasses:

BooleanVariant, NodeSetVariant, NumberVariant, ObjectVariant, PermanentNodeSetVariant, StringVariant

public abstract class VariantBase
extends Object
implements Variant

Base class of Variants.

Constructor Summary

Constructors

Constructor and Description
VariantBase()

Method Summary

Modifier and Type	Method and Description
NodeIterator	convertToNodeSet() Returns this Variant converted to a node set.
double	convertToNumber() Returns this Variant converted to a double.
boolean	convertToPredicate(ExprContext context) Used by the implementation, not useful for the application programmer.
static Variant	create(Object obj) Converts a Java object to the proper type of Variant, based on its class.
boolean	isBoolean() Returns true if this Variant is a boolean value.
boolean	isNodeSet() Returns true if this Variant is a node set value.
boolean	isNumber() Returns true if this Variant is a double value.
boolean	isString() Returns true if this Variant is a string value.
Variant	makePermanent() Used to convert a node set Variant to a permanent node set Variant.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.xmlmind.xml.xpath.Variant

convertToBoolean, convertToObject, convertToString, toString

Constructor Detail

VariantBase

public VariantBase()

Method Detail

makePermanent

public Variant makePermanent()
                      throws EvalException

Description copied from interface: Variant

Used to convert a node set Variant to a permanent node set Variant. No effect on other types of Variants.

Specified by:

makePermanent in interface Variant

Returns:

if this Variant is a node set, returns an equivalent permanent node set; otherwise return this Variant

Throws:

EvalException - if the equivalent permanent node set cannot be created (remember that node set are almost always lazily evaluated)

See Also:

NodeSetVariant, PermanentNodeSetVariant

convertToNodeSet

public NodeIterator convertToNodeSet()
                              throws EvalException

Description copied from interface: Variant

Returns this Variant converted to a node set.

Specified by:

convertToNodeSet in interface Variant

Throws:

EvalException - if this Variant cannot be converted to a node set.

convertToNumber

public double convertToNumber()
                       throws EvalException

Description copied from interface: Variant

Returns this Variant converted to a double.

Specified by:

convertToNumber in interface Variant

Throws:

EvalException - if this Variant cannot be converted to a double.

convertToPredicate

public boolean convertToPredicate(ExprContext context)
                           throws EvalException

Description copied from interface: Variant

Used by the implementation, not useful for the application programmer.

Specified by:

convertToPredicate in interface Variant

Throws:

EvalException

isBoolean

public boolean isBoolean()

Description copied from interface: Variant

Returns true if this Variant is a boolean value.

Specified by:

isBoolean in interface Variant

isNumber

public boolean isNumber()

Description copied from interface: Variant

Returns true if this Variant is a double value.

Specified by:

isNumber in interface Variant

isString

public boolean isString()

Description copied from interface: Variant

Returns true if this Variant is a string value.

Specified by:

isString in interface Variant

isNodeSet

public boolean isNodeSet()

Description copied from interface: Variant

Returns true if this Variant is a node set value.

Specified by:

isNodeSet in interface Variant

create

public static Variant create(Object obj)

Converts a Java object to the proper type of Variant, based on its class. For example, creates a StringVariant for a java.lang.String.