## com.icl.saxon.expr
Class ParentNodeExpression

    java.lang.Object
      com.icl.saxon.expr.Expression
          com.icl.saxon.expr.NodeSetExpression
              com.icl.saxon.expr.SingletonExpression
                  com.icl.saxon.expr.ParentNodeExpression

public class ParentNodeExpression
extends SingletonExpression

Class ParentNodeExpression represents the XPath expression ".." or "parent::node()"

Field Summary

Fields inherited from class com.icl.saxon.expr.Expression
`staticContext`

Constructor Summary
`ParentNodeExpression()`

Method Summary
`void` `display(int level)` Diagnostic print of expression structure
`boolean` `evaluateAsBoolean(Context context)` Evaluate as a boolean.
`java.lang.String` `evaluateAsString(Context context)` Evaluate as a string.
`int` `getDependencies()` Determine which aspects of the context the expression depends on.
`NodeInfo` `getNode(Context context)` Return the node selected by this SingletonExpression
`Expression` `reduce(int dependencies, Context context)` Perform a partial evaluation of the expression, by eliminating specified dependencies on the context.

Methods inherited from class com.icl.saxon.expr.SingletonExpression
`enumerate, evaluateAsNodeSet, isContextDocumentNodeSet, selectFirst`

Methods inherited from class com.icl.saxon.expr.NodeSetExpression
`evaluate, getDataType, outputStringValue`

Methods inherited from class com.icl.saxon.expr.Expression
`containsReferences, evaluateAsNumber, getStaticContext, indent, make, setStaticContext, simplify, usesCurrent`

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

Constructor Detail

### ParentNodeExpression

    public ParentNodeExpression()

Method Detail

### getNode

    public NodeInfo getNode(Context context)
                     throws XPathException

  Return the node selected by this SingletonExpression

  Specified by:
    `getNode` in class `SingletonExpression`
  Parameters:
    `context` - The context for the evaluation
  Returns:
    the parent of the current node defined by the context
  Throws:
    `XPathException`

### getDependencies

    public int getDependencies()

  Determine which aspects of the context the expression depends on. The result is a bitwise-or'ed value composed from constants such as Context.VARIABLES and Context.CURRENT_NODE

  Specified by:
    `getDependencies` in class `Expression`

### evaluateAsString

    public java.lang.String evaluateAsString(Context context)
                                      throws XPathException

  Evaluate as a string. Returns the string value of the parent node

  Overrides:
    `evaluateAsString` in class `SingletonExpression`
  Parameters:
    `context` - The context in which the expression is to be evaluated
  Returns:
    the value of the current node, identified by the context
  Throws:
    `XPathException`

### evaluateAsBoolean

    public boolean evaluateAsBoolean(Context context)
                              throws XPathException

  Evaluate as a boolean. Returns true if there are any nodes selected by the NodeSetExpression.

  Overrides:
    `evaluateAsBoolean` in class `SingletonExpression`
  Parameters:
    `context` - The context in which the expression is to be evaluated
  Returns:
    true unless the current node is the Document node
  Throws:
    `XPathException`

### reduce

    public Expression reduce(int dependencies,
                             Context context)
                      throws XPathException

  Perform a partial evaluation of the expression, by eliminating specified dependencies on the context.

  Specified by:
    `reduce` in class `Expression`
  Parameters:
    `dependencies` - The dependencies to be removed
    `context` - The context to be used for the partial evaluation
  Returns:
    a new expression that does not have any of the specified dependencies
  Throws:
    `XPathException`

### display

    public void display(int level)

  Diagnostic print of expression structure

  Specified by:
    `display` in class `Expression`