## net.sf.saxon.instruct
Class Copy

    java.lang.Object
      net.sf.saxon.expr.Expression
          net.sf.saxon.instruct.Instruction
              net.sf.saxon.instruct.ParentNodeConstructor
                  net.sf.saxon.instruct.ElementCreator
                      net.sf.saxon.instruct.Copy

All Implemented Interfaces:
  Serializable, SourceLocator, Container, EvaluableItem, SequenceIterable, TailCallReturner, InstructionInfoProvider

    public class Copy

extends ElementCreator

Handler for xsl:copy elements in stylesheet.

See Also:
  Serialized Form

Field Summary

Fields inherited from class net.sf.saxon.expr.Expression
`EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD`

Constructor Summary
`Copy(boolean copyNamespaces, boolean inheritNamespaces, SchemaType schemaType, int validation)`

Method Summary
`void` `display(int level, PrintStream out, Configuration config)` Diagnostic print of expression structure.
`Item` `evaluateItem(XPathContext context)` Evaluate as an expression.
`int[]` `getActiveNamespaces()` Callback to get a list of the intrinsic namespaces that need to be generated for the element.
`int` `getInstructionNameCode()` Get the name of this instruction for diagnostic and tracing purposes
`ItemType` `getItemType(TypeHierarchy th)` Get the item type of the result of this instruction.
`int` `getNameCode(XPathContext context)` Callback from ElementCreator when constructing an element
`String` `getNewBaseURI(XPathContext context)` Get the base URI of a copied element node (the base URI is retained in the new copy)
`TailCall` `processLeavingTail(XPathContext context)` Evaluate the instruction to produce a new element node.
`Expression` `simplify(StaticContext env)` Simplify an expression.

Methods inherited from class net.sf.saxon.instruct.ElementCreator
`computeSpecialProperties, getImplementationMethod, isInheritNamespaces, isValidating, setValidationMode, suppressValidation`

Methods inherited from class net.sf.saxon.instruct.ParentNodeConstructor
`computeCardinality, createsNewNodes, getBaseURI, getCardinality, getContentExpression, getSchemaType, getValidationMode, isLazyConstruction, isNamespaceSensitive, iterateSubExpressions, optimize, replaceSubExpression, setBaseURI, setContentExpression, setLazyConstruction, setSchemaType, typeCheck`

Methods inherited from class net.sf.saxon.instruct.Instruction
`appendItem, evaluateAsString, getInstructionInfo, getSourceLocator, isXSLT, iterate, process, promote`

Methods inherited from class net.sf.saxon.expr.Expression

`adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, effectiveBooleanValue, getColumnNumber, getContainingProcedure, getDependencies, getExecutable, getHostLanguage, getIntrinsicDependencies, getLineNumber, getLocationId, getLocationProvider, getParentExpression, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasBadParentPointer, markTailFunctionCalls, resetStaticProperties, setLocationId, setParentExpression, setParentExpression`

Methods inherited from class java.lang.Object
`equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Methods inherited from interface javax.xml.transform.SourceLocator
`getColumnNumber, getLineNumber, getPublicId, getSystemId`

Constructor Detail

### Copy

    public Copy(boolean copyNamespaces,
                boolean inheritNamespaces,
                SchemaType schemaType,
                int validation)

Method Detail

### simplify

    public Expression simplify(StaticContext env)
                        throws XPathException

  Simplify an expression. This performs any static optimization (by rewriting the expression as a different expression). The default implementation does nothing.

  Overrides:
    `simplify` in class `ParentNodeConstructor`
  Returns:
    the simplified expression
  Throws:
    `XPathException` - if an error is discovered during expression rewriting

### getInstructionNameCode

    public int getInstructionNameCode()

  Get the name of this instruction for diagnostic and tracing purposes

  Overrides:
    `getInstructionNameCode` in class `Instruction`

### getItemType

    public ItemType getItemType(TypeHierarchy th)

  Get the item type of the result of this instruction.

  Overrides:
    `getItemType` in class `ElementCreator`
  Parameters:
    `th` -
  Returns:
    The context item type.

### getNameCode

    public int getNameCode(XPathContext context)
                    throws XPathException

  Callback from ElementCreator when constructing an element

  Specified by:
    `getNameCode` in class `ElementCreator`
  Parameters:
    `context` -
  Returns:
    the namecode of the element to be constructed
  Throws:
    `XPathException`

### getNewBaseURI

    public String getNewBaseURI(XPathContext context)

  Get the base URI of a copied element node (the base URI is retained in the new copy)

  Specified by:
    `getNewBaseURI` in class `ElementCreator`
  Parameters:
    `context` -
  Returns:
    the base URI

### getActiveNamespaces

    public int[] getActiveNamespaces()
                              throws XPathException

  Callback to get a list of the intrinsic namespaces that need to be generated for the element. The result is an array of namespace codes, the codes either occupy the whole array or are terminated by a -1 entry. A result of null is equivalent to a zero-length array.

  Overrides:
    `getActiveNamespaces` in class `ElementCreator`
  Throws:
    `XPathException`

### processLeavingTail

    public TailCall processLeavingTail(XPathContext context)
                                throws XPathException

  Description copied from class: `ElementCreator`
  Evaluate the instruction to produce a new element node. This method is typically used when there is a parent element or document in a result tree, to which the new element is added.

  Specified by:
    `processLeavingTail` in interface `TailCallReturner`
  Overrides:
    `processLeavingTail` in class `ElementCreator`
  Parameters:
    `context` - The dynamic context of the transformation, giving access to the current node, the current variables, etc.
  Returns:
    null (this instruction never returns a tail call)
  Throws:
    `XPathException`

### evaluateItem

    public Item evaluateItem(XPathContext context)
                      throws XPathException

  Evaluate as an expression. We rely on the fact that when these instructions are generated by XQuery, there will always be a valueExpression to evaluate the content

  Specified by:
    `evaluateItem` in interface `EvaluableItem`
  Overrides:
    `evaluateItem` in class `ElementCreator`
  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

### display

    public void display(int level,
                        PrintStream out,
                        Configuration config)

  Diagnostic print of expression structure. The expression is written to the System.err output stream

  Specified by:
    `display` in class `Expression`
  Parameters:
    `level` - indentation level for this expression
    `out` -
    `config` -

Copyright (C) Michael H. Kay. All rights reserved.