com.qizx.api
Interface XQueryContext

public interface XQueryContext

Definition of the XQuery Context used for compiling and executing Expressions. This serves both as Static and Dynamic context (in the sense of XQuery).

A XML Library provides a default XQueryContext which can be modified. This default context should be suitable for most applications, with perhaps only a few properties to define, such as base-uri.

Before an Expression is compiled, it inherits the context of the Library from which the expression is created.

After an Expression is compiled, its XQueryContext reflects declarations made in the expression itself. The XQuery context can be inspected and runtime properties modified (mainly the default collation, implicit timezone, current date).

Field Summary

static int	INHERIT Value used for property NamespaceInheritMode, meaning that namespaces should be inherited in a node copy operation.
static int	NO_INHERIT Value used for property NamespaceInheritMode, meaning that namespaces should not be inherited in a node copy operation.
static int	NO_PRESERVE Value used for properties BoundarySpacePolicy, NamespacePreserveMode, ConstructionMode, meaning that - respectively - boundary space, namespaces and schema types should not be preserved.
static int	ORDERED Value returned by getOrderingMode(): indicates that by default result sequences must be ordered.
static int	PRESERVE Value used for properties BoundarySpacePolicy, NamespacePreserveMode, ConstructionMode, meaning that - respectively - boundary space, namespaces and schema types should be preserved.
static int	UNORDERED Value returned by getOrderingMode(): indicates that by default result sequences are not required to be ordered.

Method Summary

void	declarePrefix(String prefix, String namespaceURI) Adds a predefined namespace declaration.
void	declareVariable(QName variableName, SequenceType variableType) Adds a predefined variable declaration.
String	getBaseURI() Gets the base URI used to resolve relative URIs in expressions.
int	getBoundarySpacePolicy() Gets the default boundary space policy for element constructors.
int	getConstructionMode() Gets the construction mode defined in the static context.
Date	getCurrentDate() Gets the specific date/time set by setCurrentDate().
String	getDefaultCollation() Gets the URI of the default collation defined in the static context.
String	getDefaultElementNamespace() Gets the URI of the default element namespace.
String	getDefaultFunctionNamespace() Gets the URI of the default function namespace.
boolean	getDefaultOrderEmptyGreatest() Gets the default order for empty sequences in 'order by' clauses.
TimeZone	getImplicitTimeZone() Returns the current implicit time-zone in the execution context.
String[]	getInScopePrefixes() Returns the prefixes of in-scope namespace definitions.
int	getNamespaceInheritMode() Gets the default inherit part of the copy-namespaces mode.
int	getNamespacePreserveMode() Gets the default preserve part of the copy-namespaces mode.
String	getNamespaceURI(String prefix) Retrieves the namespace URI associated with a prefix.
int	getOrderingMode() Gets the default ordering mode for returned sequences.
boolean	getStrictCompliance() Returns true if a strict compliance with XQuery Specifications is enforced (not allowing extensions).
QName[]	getVariableNames() Gets the list of global variables declared in the static context.
SequenceType	getVariableType(QName variableName) Returns the type associated with a declared variable.
String	getXQueryVersion() Gets the supported version of XQuery.
void	setBaseURI(String uri) Sets the base URI used to resolve relative URIs in expressions.
void	setBoundarySpacePolicy(int boundarySpacePolicy) Sets the default boundary space policy for element constructors.
void	setConstructionMode(int constructionMode) Sets the construction mode defined in the static context.
void	setCurrentDate(Date forcedDate) Sets a specific date/time for use in query evaluation, instead of the normal value (the system time at start of evaluation).
void	setDefaultCollation(String defaultCollation) Sets the URI of the default collation defined in the static context.
void	setDefaultElementNamespace(String defaultElementNamespace) Sets the URI of the default element namespace.
void	setDefaultFunctionNamespace(String defaultFunctionNamespace) Sets the URI of the default function namespace.
void	setDefaultOrderEmptyGreatest(boolean emptyGreatest) Sets the default order for empty sequences in 'order by' clauses.
void	setImplicitTimeZone(TimeZone implicitTimeZone) Defines the implicit time-zone in the execution context.
void	setNamespaceInheritMode(int namespaceInheritMode) Sets the default inherit part of the copy-namespaces mode.
void	setNamespacePreserveMode(int namespacePreserveMode) Sets the default preserve part of the copy-namespaces mode.
void	setOrderingMode(int orderingMode) Sets the default ordering mode for returned sequences.
void	setStrictCompliance(boolean strictCompliance) Sets the strict compliance flag with XQuery Specifications.

Field Detail

ORDERED

public static final int ORDERED

Value returned by getOrderingMode(): indicates that by default result sequences must be ordered.

See Also:

Constant Field Values

UNORDERED

public static final int UNORDERED

Value returned by getOrderingMode(): indicates that by default result sequences are not required to be ordered.

See Also:

Constant Field Values

PRESERVE

public static final int PRESERVE

Value used for properties BoundarySpacePolicy, NamespacePreserveMode, ConstructionMode, meaning that - respectively - boundary space, namespaces and schema types should be preserved.

See Also:

Constant Field Values

NO_PRESERVE

public static final int NO_PRESERVE

Value used for properties BoundarySpacePolicy, NamespacePreserveMode, ConstructionMode, meaning that - respectively - boundary space, namespaces and schema types should not be preserved.

See Also:

Constant Field Values

INHERIT

public static final int INHERIT

Value used for property NamespaceInheritMode, meaning that namespaces should be inherited in a node copy operation.

See Also:

Constant Field Values

NO_INHERIT

public static final int NO_INHERIT

Value used for property NamespaceInheritMode, meaning that namespaces should not be inherited in a node copy operation.

See Also:

Constant Field Values

Method Detail

getXQueryVersion

public String getXQueryVersion()

Gets the supported version of XQuery.

Returns:

a String representing the XQuery version value

getDefaultOrderEmptyGreatest

public boolean getDefaultOrderEmptyGreatest()

Gets the default order for empty sequences in 'order by' clauses.

Returns:

true if the empty sequence or NaN are considered greatest.

setDefaultOrderEmptyGreatest

public void setDefaultOrderEmptyGreatest(boolean emptyGreatest)

Sets the default order for empty sequences in 'order by' clauses.

Parameters:

emptyGreatest - true if the empty sequence or NaN are considered greatest.

getNamespaceInheritMode

public int getNamespaceInheritMode()

Gets the default inherit part of the copy-namespaces mode.

Returns:

the inherit mode, one of the two values INHERIT or NO_INHERIT

setNamespaceInheritMode

public void setNamespaceInheritMode(int namespaceInheritMode)

Sets the default inherit part of the copy-namespaces mode.

Parameters:

namespaceInheritMode - the inherit mode to set, one of the two values INHERIT or NO_INHERIT

getNamespacePreserveMode

public int getNamespacePreserveMode()

Gets the default preserve part of the copy-namespaces mode.

Returns:

the default namespace preserve mode, one of the two values PRESERVE or NO_PRESERVE.

setNamespacePreserveMode

public void setNamespacePreserveMode(int namespacePreserveMode)

Sets the default preserve part of the copy-namespaces mode.

Parameters:

namespacePreserveMode - the namespace preserve mode to set, one of the two values PRESERVE or NO_PRESERVE.

getBoundarySpacePolicy

public int getBoundarySpacePolicy()

Gets the default boundary space policy for element constructors.

Returns:

the default boundary space policy, one of the two values PRESERVE or NO_PRESERVE.

setBoundarySpacePolicy

public void setBoundarySpacePolicy(int boundarySpacePolicy)

Sets the default boundary space policy for element constructors.

Parameters:

boundarySpacePolicy - the boundary space policy to set, one of the two values PRESERVE or NO_PRESERVE.

getConstructionMode

public int getConstructionMode()

Gets the construction mode defined in the static context.

Returns:

the default construction mode to set, one of the two values PRESERVE or NO_PRESERVE.

setConstructionMode

public void setConstructionMode(int constructionMode)

Sets the construction mode defined in the static context.

Parameters:

constructionMode - the construction mode to set, one of the two values PRESERVE or NO_PRESERVE.

getDefaultCollation

public String getDefaultCollation()

Gets the URI of the default collation defined in the static context. By default it is the Unicode codepoints collation.

Returns:

the defaultCollation

setDefaultCollation

public void setDefaultCollation(String defaultCollation)
                         throws DataModelException

Sets the URI of the default collation defined in the static context.

Parameters:

defaultCollation - the URI of the default collation to set

Throws:

DataModelException - if the collation cannot be resolved

getDefaultElementNamespace

public String getDefaultElementNamespace()

Gets the URI of the default element namespace. By default it is the blank namespace.

Returns:

the default element namespace

setDefaultElementNamespace

public void setDefaultElementNamespace(String defaultElementNamespace)

Sets the URI of the default element namespace.

Parameters:

defaultElementNamespace - default element namespace to set

getDefaultFunctionNamespace

public String getDefaultFunctionNamespace()

Gets the URI of the default function namespace. By default it corresponds to predefined functions (prefix fn:).

Returns:

the URI of the default function namespace, if set, else the empty string.

setDefaultFunctionNamespace

public void setDefaultFunctionNamespace(String defaultFunctionNamespace)

Sets the URI of the default function namespace.

Parameters:

defaultFunctionNamespace - the default Function Namespace to set, may not be null

getOrderingMode

public int getOrderingMode()

Gets the default ordering mode for returned sequences.

Returns:

the orderingMode, one of the two values ORDERED or UNORDERED

setOrderingMode

public void setOrderingMode(int orderingMode)

Sets the default ordering mode for returned sequences.

Parameters:

orderingMode - the ordering mode to set, one of the two values ORDERED or UNORDERED

getBaseURI

public String getBaseURI()

Gets the base URI used to resolve relative URIs in expressions.

Returns:

the base URI, if set, else the empty string. Cannot be null

setBaseURI

public void setBaseURI(String uri)

Sets the base URI used to resolve relative URIs in expressions.

Parameters:

uri - the base URI, or the empty string. May not be null

getInScopePrefixes

public String[] getInScopePrefixes()

Returns the prefixes of in-scope namespace definitions. If used on the context of a compiled Expression,

Returns:

String array containing the namespace prefixes. Cannot be null.

declarePrefix

public void declarePrefix(String prefix,
                          String namespaceURI)

Adds a predefined namespace declaration.

If a namespace with the same prefix already exists, it is replaced.

Parameters:

prefix - namespace prefix to be declared

namespaceURI - URi of the namespace to be declared

getNamespaceURI

public String getNamespaceURI(String prefix)

Retrieves the namespace URI associated with a prefix.

Parameters:

prefix - a namespace prefix

Returns:

the namespaceURI associated with the prefix, or null if the prefix is undefined.

getVariableNames

public QName[] getVariableNames()

Gets the list of global variables declared in the static context.

In the context of an Expression, the variables are those declared in the expression. In the context of a XQuerySesison (or Library), the variables can only have been predefined through the method declareVariable(QName, SequenceType).

Returns:

array of QNames of the variables. An empty array is returned when there are no variables.

getVariableType

public SequenceType getVariableType(QName variableName)

Returns the type associated with a declared variable.

Parameters:

variableName - qualified name of the variable

Returns:

the type declared for the variable. If the variable is not declared, returns null.

declareVariable

public void declareVariable(QName variableName,
                            SequenceType variableType)

Adds a predefined variable declaration.

Parameters:

variableName - qualified name of the variable

variableType - optional type (may be null) declared for the variable

setImplicitTimeZone

public void setImplicitTimeZone(TimeZone implicitTimeZone)

Defines the implicit time-zone in the execution context.

Parameters:

implicitTimeZone - a TimeZone to be used as implicit time-zone

getImplicitTimeZone

public TimeZone getImplicitTimeZone()

Returns the current implicit time-zone in the execution context. By default it is the system time-zone.

Returns:

the current implicit time-zone

getStrictCompliance

public boolean getStrictCompliance()

Returns true if a strict compliance with XQuery Specifications is enforced (not allowing extensions).

Returns:

true if strict compliance is enforced

See Also:

setStrictCompliance(boolean)

setStrictCompliance

public void setStrictCompliance(boolean strictCompliance)

Sets the strict compliance flag with XQuery Specifications.

If not enabled (the default), the following extensions are available:

Casting numeric values from/to xs:date, xs:time, xs:dateTime, xs:dayTimeDuration, xs:yearMonthDuration.

Allow concat() to have a single argument which is a sequence.

Parameters:

strictCompliance - true to enforce strict compliance

setCurrentDate

public void setCurrentDate(Date forcedDate)

Sets a specific date/time for use in query evaluation, instead of the normal value (the system time at start of evaluation).

Parameters:

forcedDate - a date/time, or null to use again the system time.

getCurrentDate

public Date getCurrentDate()

Gets the specific date/time set by setCurrentDate().

Returns:

the value set by setCurrentDate(), or null by default (use system time)