org.basex.query

Class QueryProcessor

java.lang.Object

org.basex.core.Progress

org.basex.query.QueryProcessor

public final class QueryProcessor
extends Progress

This class is an entry point for evaluating XQuery implementations.

Author:

BaseX Team 2005-12, BSD License, Christian Gruen

Field Summary

Fields

Modifier and Type	Field and Description
QueryContext	ctx Expression context.

Fields inherited from class org.basex.core.Progress

updating

Constructor Summary

Constructors

Constructor and Description
QueryProcessor(java.lang.String qu, Context cx) Default constructor.

Method Summary

Methods

Modifier and Type	Method and Description
QueryProcessor	bind(java.lang.String name, java.lang.Object value) Binds a value to a global variable.
QueryProcessor	bind(java.lang.String name, java.lang.Object value, java.lang.String type) Binds a value with the specified data type to a global variable.
void	close() Closes the processor.
void	compile() Compiles the query.
QueryProcessor	context(Nodes nodes) Binds an initial nodeset to the context item.
QueryProcessor	context(java.lang.Object value) Binds a value to the context item.
QueryProcessor	context(java.lang.Object value, java.lang.String type) Binds a value with the specified data type to the context item, using the same rules as for binding variables.
java.lang.String	det() Returns short information on this process.
Result	execute() Evaluates the specified query and returns the result.
Serializer	getSerializer(java.io.OutputStream os) Returns a serializer for the given output stream.
java.lang.String	info() Returns query background information.
Iter	iter() Returns a result iterator.
void	module(java.lang.String uri, java.lang.String file) Adds a module reference.
QueryProcessor	namespace(java.lang.String prefix, java.lang.String uri) Declares a namespace.
void	parse() Parses the query.
void	plan(Serializer ser) Returns the query plan in the dot notation.
java.lang.String	query() Returns the query string.
void	query(java.lang.String qu) Sets a new query.
Nodes	queryNodes() Evaluates the specified query and returns the result nodes.
static java.lang.String	removeComments(java.lang.String qu, int max) Removes comments from the specified string.
java.lang.String	tit() Returns short information on this process.
int	updates() Returns the number of performed updates after query execution, or 0.
Value	value() Returns a result value.

Methods inherited from class org.basex.core.Progress

abort, checkStop, detail, prog, progress, progress, startTimeout, stop, stopTimeout, title

Methods inherited from class java.lang.Object

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

Field Detail

ctx

public final QueryContext ctx

Expression context.

Constructor Detail

QueryProcessor

public QueryProcessor(java.lang.String qu,
              Context cx)

Default constructor.

Parameters:

qu - query to process

cx - database context

Method Detail

parse

public void parse()
           throws QueryException

Parses the query.

Throws:

QueryException - query exception

compile

public void compile()
             throws QueryException

Compiles the query.

Throws:

QueryException - query exception

iter

public Iter iter()
          throws QueryException

Returns a result iterator.

Returns:

result iterator

Throws:

QueryException - query exception

value

public Value value()
            throws QueryException

Returns a result value.

Returns:

result value

Throws:

QueryException - query exception

execute

public Result execute()
               throws QueryException

Evaluates the specified query and returns the result.

Returns:

result of query

Throws:

QueryException - query exception

bind

public QueryProcessor bind(java.lang.String name,
                  java.lang.Object value,
                  java.lang.String type)
                    throws QueryException

Binds a value with the specified data type to a global variable. If the value is an Expr instance, it is directly assigned. Otherwise, it is first cast to the appropriate XQuery type. If "json" is specified as data type, the value is interpreted according to the rules specified in JsonMapConverter.

Parameters:

name - name of variable

value - value to be bound

type - data type (may be null)

Returns:

self reference

Throws:

QueryException - query exception

bind

public QueryProcessor bind(java.lang.String name,
                  java.lang.Object value)
                    throws QueryException

Binds a value to a global variable.

Parameters:

name - name of variable

value - value to be bound

Returns:

self reference

Throws:

QueryException - query exception

context

public QueryProcessor context(java.lang.Object value)
                       throws QueryException

Binds a value to the context item.

Parameters:

value - value to be bound

Returns:

self reference

Throws:

QueryException - query exception

context

public QueryProcessor context(java.lang.Object value,
                     java.lang.String type)
                       throws QueryException

Binds a value with the specified data type to the context item, using the same rules as for binding variables.

Parameters:

value - value to be bound

type - data type (may be null)

Returns:

self reference

Throws:

QueryException - query exception

context

public QueryProcessor context(Nodes nodes)

Binds an initial nodeset to the context item.

Parameters:

nodes - node set

Returns:

self reference

namespace

public QueryProcessor namespace(java.lang.String prefix,
                       java.lang.String uri)
                         throws QueryException

Declares a namespace. A namespace is undeclared if the uri is an empty string. The default element namespaces is set if the prefix is empty.

Parameters:

prefix - namespace prefix

uri - namespace uri

Returns:

self reference

Throws:

QueryException - query exception

getSerializer

public Serializer getSerializer(java.io.OutputStream os)
                         throws java.io.IOException,
                                QueryException

Returns a serializer for the given output stream. Optional output declarations within the query will be included in the serializer instance.

Parameters:

os - output stream

Returns:

serializer instance

Throws:

java.io.IOException - query exception

QueryException - query exception

queryNodes

public Nodes queryNodes()
                 throws QueryException

Evaluates the specified query and returns the result nodes.

Returns:

result nodes

Throws:

QueryException - query exception

module

public void module(java.lang.String uri,
          java.lang.String file)

Adds a module reference.

Parameters:

uri - module uri

file - file name

query

public void query(java.lang.String qu)

Sets a new query. Should be called before parsing the query.

Parameters:

qu - query

query

public java.lang.String query()

Returns the query string.

Returns:

query

close

public void close()
           throws QueryException

Closes the processor.

Throws:

QueryException - query exception

updates

public int updates()

Returns the number of performed updates after query execution, or 0.

Returns:

number of updates

info

public java.lang.String info()

Returns query background information.

Returns:

background information

removeComments

public static java.lang.String removeComments(java.lang.String qu,
                              int max)

Removes comments from the specified string.

Parameters:

qu - query string

max - maximum string length

Returns:

result

plan

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

Returns the query plan in the dot notation.

Parameters:

ser - serializer

Throws:

java.io.IOException - I/O exception

tit

public java.lang.String tit()

Description copied from class: Progress

Returns short information on this process. Can be overwritten to give more detailed information.

Overrides:

tit in class Progress

Returns:

header information

det

public java.lang.String det()

Description copied from class: Progress

Returns short information on this process.

Overrides:

det in class Progress

Returns:

header information