net.sf.saxon.instruct
Class DocumentInstr

java.lang.Object
  |
  +--net.sf.saxon.expr.ComputedExpression
        |
        +--net.sf.saxon.instruct.Instruction
              |
              +--net.sf.saxon.instruct.InstructionWithChildren
                    |
                    +--net.sf.saxon.instruct.DocumentInstr
All Implemented Interfaces:
Container, Expression, InstructionInfoProvider, java.io.Serializable, javax.xml.transform.SourceLocator

public class DocumentInstr
extends InstructionWithChildren

An instruction to create a document node. This doesn't correspond directly to any XSLT instruction. It is used to support the document node constructor expression in XQuery, and is used as a sub-instruction within an xsl:variable that constructs a temporary tree.

Conceptually it represents an XSLT instruction xsl:document-node, with no attributes, whose content is a complex content constructor for the children of the document node.

See Also:
Serialized Form

Field Summary
 
Fields inherited from class net.sf.saxon.instruct.InstructionWithChildren
children
 
Fields inherited from class net.sf.saxon.expr.ComputedExpression
locationId, staticProperties
 
Fields inherited from interface net.sf.saxon.expr.Expression
EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD
 
Constructor Summary
DocumentInstr(boolean textOnly, java.lang.String constantText, java.lang.String baseURI)
           
 
Method Summary
 void display(int level, NamePool pool, java.io.PrintStream out)
          Display this instruction as an expression, for diagnostics
 Item evaluateItem(XPathContext context)
          Evaluate as an expression.
 int getCardinality()
          Determine the static cardinality of the expression.
 int getInstructionNameCode()
          Get the name of this instruction for diagnostic and tracing purposes (the string "document-constructor")
 ItemType getItemType()
          Get the item type of the items returned by evaluating this instruction
 TailCall processLeavingTail(XPathContext context)
          ProcessLeavingTail: called to do the real work of this instruction.
 void setSchemaType(SchemaType type)
          Set the SchemaType of the document element
 void setValidationAction(int action)
          Set the validation action
 
Methods inherited from class net.sf.saxon.instruct.InstructionWithChildren
analyze, displayChildren, getChildren, iterateSubExpressions, processChildren, processChildrenLeavingTail, promoteInst, setChildren, simplify
 
Methods inherited from class net.sf.saxon.instruct.Instruction
appendItem, assembleParams, assembleTunnelParams, computeCardinality, computeSpecialProperties, dynamicError, dynamicError, effectiveBooleanValue, evaluateAsString, getImplementationMethod, getInstructionInfo, getSourceLocator, iterate, process, promote
 
Methods inherited from class net.sf.saxon.expr.ComputedExpression
adoptChildExpression, computeDependencies, computeStaticProperties, dynamicError, dynamicError, getColumnNumber, getConstructType, getDependencies, getExecutable, getIntrinsicDependencies, getLineNumber, getLocationId, getParentExpression, getPublicId, getSpecialProperties, getSystemId, markTailFunctionCalls, resetStaticProperties, setLocationId, setParentExpression, typeError
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface javax.xml.transform.SourceLocator
getColumnNumber, getLineNumber, getPublicId, getSystemId
 

Constructor Detail

DocumentInstr

public DocumentInstr(boolean textOnly,
                     java.lang.String constantText,
                     java.lang.String baseURI)
Method Detail

setValidationAction

public void setValidationAction(int action)
Set the validation action


setSchemaType

public void setSchemaType(SchemaType type)
Set the SchemaType of the document element


getItemType

public ItemType getItemType()
Description copied from class: Instruction
Get the item type of the items returned by evaluating this instruction

Specified by:
getItemType in interface Expression
Overrides:
getItemType in class Instruction
Returns:
the static item type of the instruction

getCardinality

public int getCardinality()
Description copied from class: ComputedExpression
Determine the static cardinality of the expression. This establishes how many items there will be in the result of the expression, at compile time (i.e., without actually evaluating the result.

Specified by:
getCardinality in interface Expression
Overrides:
getCardinality in class ComputedExpression
Returns:
one of the values Cardinality.ONE_OR_MORE, Cardinality.ZERO_OR_MORE, Cardinality.EXACTLY_ONE, Cardinality.ZERO_OR_ONE, Cardinality.EMPTY. This default implementation returns ZERO_OR_MORE (which effectively gives no information).

processLeavingTail

public TailCall processLeavingTail(XPathContext context)
                            throws XPathException
Description copied from class: Instruction
ProcessLeavingTail: called to do the real work of this instruction. This method must be implemented in each subclass. The results of the instruction are written to the current Receiver, which can be obtained via the Controller.

Specified by:
processLeavingTail in class Instruction
Parameters:
context - The dynamic context of the transformation, giving access to the current node, the current variables, etc.
Returns:
null if the instruction has completed execution; or a TailCall indicating a function call or template call that is delegated to the caller, to be made after the stack has been unwound so as to save stack space.
XPathException

evaluateItem

public Item evaluateItem(XPathContext context)
                  throws XPathException
Evaluate as an expression.

Specified by:
evaluateItem in interface Expression
Overrides:
evaluateItem in class Instruction
Parameters:
context - The context in which the expression is to be evaluated
Returns:
the node or atomic value that results from evaluating the expression; or null to indicate that the result is an empty sequence
Throws:
XPathException - if any dynamic error occurs evaluating the expression

getInstructionNameCode

public int getInstructionNameCode()
Get the name of this instruction for diagnostic and tracing purposes (the string "document-constructor")

Overrides:
getInstructionNameCode in class Instruction

display

public void display(int level,
                    NamePool pool,
                    java.io.PrintStream out)
Display this instruction as an expression, for diagnostics

Parameters:
level - indentation level for this expression
pool - NamePool used to expand any names appearing in the expression
out - Output destination