Class Error

All Implemented Interfaces:
Callable, FunctionItem, GroundedValue, Item, Sequence

public class Error extends SystemFunction implements Callable
Implement XPath function fn:error()
  • Constructor Details

    • Error

      public Error()
  • Method Details

    • getSpecialProperties

      public int getSpecialProperties(Expression[] arguments)
      Description copied from class: SystemFunction
      Determine the special properties of this function. The general rule is that a system function call is non-creative unless more details are defined in a subclass.
      Overrides:
      getSpecialProperties in class SystemFunction
      Parameters:
      arguments - the actual arguments supplied in a call to the function
      Returns:
      the properties
    • isVacuousExpression

      public boolean isVacuousExpression()
      Determine whether this is a vacuous expression as defined in the XQuery update specification
      Returns:
      true if this expression is vacuous
    • error

      public Item error(XPathContext context, QNameValue errorCode, StringValue desc, SequenceIterator errObject) throws XPathException
      Throws:
      XPathException
    • call

      public Sequence call(XPathContext context, Sequence[] arguments) throws XPathException
      Description copied from interface: Callable
      Call the Callable.
      Specified by:
      call in interface Callable
      Parameters:
      context - the dynamic evaluation context
      arguments - the values of the arguments, supplied as Sequences.

      Generally it is advisable, if calling iterate() to process a supplied sequence, to call it only once; if the value is required more than once, it should first be converted to a GroundedValue by calling the utility method SequenceTool.toGroundedValue().

      If the expected value is a single item, the item should be obtained by calling Sequence.head(): it cannot be assumed that the item will be passed as an instance of Item or AtomicValue.

      It is the caller's responsibility to perform any type conversions required to convert arguments to the type expected by the callee. An exception is where this Callable is explicitly an argument-converting wrapper around the original Callable.

      Returns:
      the result of the evaluation, in the form of a Sequence. It is the responsibility of the callee to ensure that the type of result conforms to the expected result type.
      Throws:
      XPathException - if a dynamic error occurs during the evaluation of the expression