## net.sf.saxon.expr
Class PositionRange

    java.lang.Object
      net.sf.saxon.expr.ComputedExpression
          net.sf.saxon.expr.PositionRange

All Implemented Interfaces:
  Container, Expression, InstructionInfoProvider, java.io.Serializable, javax.xml.transform.SourceLocator

public final class PositionRange
extends ComputedExpression

PositionRange: a boolean expression that tests whether the position() is within a certain range. This expression can occur in any context but it is optimized when it appears as a predicate (see FilterIterator)

See Also:
  Serialized Form

Field Summary

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
`PositionRange(int min, int max)` Create a position range

Method Summary
`Expression` `analyze(StaticContext env, ItemType contextItemType)` Type-check the expression
`int` `computeCardinality()` Determine the static cardinality
`int` `computeSpecialProperties()` Determine the special properties of this expression
`void` `display(int level, NamePool pool, java.io.PrintStream out)` Diagnostic print of expression structure
`Item` `evaluateItem(XPathContext c)` Evaluate the expression
`int` `getIntrinsicDependencies()` Get the dependencies
`ItemType` `getItemType()` Determine the data type of the expression
`int` `getMaxPosition()` Get the maximum position
`int` `getMinPosition()` Get the minimum position
`Expression` `simplify(StaticContext env)` Simplify an expression

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

`adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, dynamicError, dynamicError, effectiveBooleanValue, evaluateAsString, getCardinality, getColumnNumber, getConstructType, getDependencies, getExecutable, getImplementationMethod, getInstructionInfo, getLineNumber, getLocationId, getParentExpression, getPublicId, getSpecialProperties, getSystemId, iterate, iterateSubExpressions, markTailFunctionCalls, process, promote, resetStaticProperties, setLocationId, setParentExpression, typeError, typeError`

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

Constructor Detail

### PositionRange

    public PositionRange(int min,
                         int max)

  Create a position range

Method Detail

### simplify

    public Expression simplify(StaticContext env)
                        throws StaticError

  Simplify an expression

  Specified by:
    `simplify` in interface `Expression`
  Overrides:
    `simplify` in class `ComputedExpression`
  Returns:
    the simplified expression
  Throws:
    `StaticError`

### analyze

    public Expression analyze(StaticContext env,
                              ItemType contextItemType)

  Type-check the expression

  Parameters:
    `env` - the static context of the expression
    `contextItemType` - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to `Type.ITEM_TYPE`
  Returns:
    the original expression, rewritten to perform necessary run-time type checks, and to perform other type-related optimizations

### computeSpecialProperties

    public int computeSpecialProperties()

  Determine the special properties of this expression

  Overrides:
    `computeSpecialProperties` in class `ComputedExpression`
  Returns:
    `StaticProperty.NON_CREATIVE`.

### evaluateItem

    public Item evaluateItem(XPathContext c)
                      throws XPathException

  Evaluate the expression

  Specified by:
    `evaluateItem` in interface `Expression`
  Overrides:
    `evaluateItem` in class `ComputedExpression`
  Parameters:
    `c` - 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

### getItemType

    public ItemType getItemType()

  Determine the data type of the expression

  Returns:
    Type.BOOLEAN

### computeCardinality

    public int computeCardinality()

  Determine the static cardinality

  Specified by:
    `computeCardinality` in class `ComputedExpression`

### getIntrinsicDependencies

    public int getIntrinsicDependencies()

  Get the dependencies

  Overrides:
    `getIntrinsicDependencies` in class `ComputedExpression`
  Returns:
    a set of bit-significant flags identifying the "intrinsic" dependencies. The flags are documented in class net.sf.saxon.value.StaticProperty

### getMinPosition

    public int getMinPosition()

  Get the minimum position

### getMaxPosition

    public int getMaxPosition()

  Get the maximum position

### display

    public void display(int level,
                        NamePool pool,
                        java.io.PrintStream out)

  Diagnostic print of expression structure

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