org.basex.query.path

Class AxisStep

java.lang.Object

org.basex.data.ExprInfo

org.basex.query.expr.Expr

org.basex.query.expr.ParseExpr

org.basex.query.expr.Preds

org.basex.query.path.AxisStep

public class AxisStep
extends Preds

Location Step expression.

Author:

BaseX Team 2005-12, BSD License, Christian Gruen

Nested Class Summary

Nested classes/interfaces inherited from class org.basex.query.expr.Expr

Expr.Use

Field Summary

Fields

Modifier and Type	Field and Description
Test	test Kind test.

Fields inherited from class org.basex.query.expr.Preds

last, pos, preds

Fields inherited from class org.basex.query.expr.ParseExpr

input, size, type

Method Summary

Methods

Modifier and Type	Method and Description
Expr	comp(QueryContext ctx) Compiles and optimizes the expression, assigns data types and cardinalities.
static AxisStep	get(AxisStep s) This method creates a copy from the specified step.
static AxisStep	get(InputInfo ii, Axis a, Test t, Expr... p) This method creates a step instance.
NodeIter	iter(QueryContext ctx) Evaluates the expression and returns an iterator on the resulting items.
void	plan(Serializer ser) Serializes the expression tree.
boolean	sameAs(Expr cmp) Compares the current and specified expression for equality.
boolean	simple(Axis ax, boolean name) Checks if this is a simple axis without predicates.
java.lang.String	toString()

Methods inherited from class org.basex.query.expr.Preds

count, preds, removable, remove, useIterator, uses

Methods inherited from class org.basex.query.expr.ParseExpr

checkBln, checkColl, checkCreate, checkCtx, checkDbl, checkDBNode, checkEStr, checkEStr, checkIO, checkItem, checkItr, checkItr, checkMap, checkNode, checkNoEmpty, checkStr, checkType, checkUp, checkUp, checkWrite, compBln, ebv, item, optPre, preEval, size, test, type, value

Methods inherited from class org.basex.query.expr.Expr

addText, compEbv, hasFreeVars, indexAccessible, indexEquivalent, isEmpty, isFunction, isItem, isVacuous, isValue, iterable, markTailCalls

Methods inherited from class org.basex.data.ExprInfo

description, info

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

test

public Test test

Kind test.

Method Detail

get

public static AxisStep get(AxisStep s)

This method creates a copy from the specified step.

Parameters:

s - step to be copied

Returns:

step

get

public static AxisStep get(InputInfo ii,
           Axis a,
           Test t,
           Expr... p)

This method creates a step instance.

Parameters:

ii - input info

a - axis

t - node test

p - predicates

Returns:

step

comp

public final Expr comp(QueryContext ctx)
                throws QueryException

Description copied from class: Expr

Compiles and optimizes the expression, assigns data types and cardinalities.

Overrides:

comp in class Preds

Parameters:

ctx - query context

Returns:

optimized expression

Throws:

QueryException - query exception

iter

public NodeIter iter(QueryContext ctx)
              throws QueryException

Description copied from class: Expr

Evaluates the expression and returns an iterator on the resulting items. If this method is not overwritten, Expr.item(org.basex.query.QueryContext, org.basex.util.InputInfo) must be implemented by an expression, as it may be called by this method.

Overrides:

iter in class ParseExpr

Parameters:

ctx - query context

Returns:

resulting item

Throws:

QueryException - query exception

simple

public final boolean simple(Axis ax,
             boolean name)

Checks if this is a simple axis without predicates.

Parameters:

ax - axis to be checked

name - name/node test

Returns:

result of check

sameAs

public final boolean sameAs(Expr cmp)

Description copied from class: Expr

Compares the current and specified expression for equality.

Overrides:

sameAs in class Expr

Parameters:

cmp - expression to be compared

Returns:

result of check

plan

public final void plan(Serializer ser)
                throws java.io.IOException

Description copied from class: ExprInfo

Serializes the expression tree.

Overrides:

plan in class Preds

Parameters:

ser - serializer

Throws:

java.io.IOException - I/O exception

toString

public final java.lang.String toString()

Overrides:

toString in class Preds