org.basex.server

Class Query

java.lang.Object

org.basex.server.Query

Direct Known Subclasses:

ClientQuery, LocalQuery

public abstract class Query
extends java.lang.Object

This class defines methods for executing queries. It is implemented by ClientQuery.

Results are either returned as string or serialized to the output stream that has been specified via the constructor or via Session.setOutputStream(OutputStream).

Author:

BaseX Team 2005-12, BSD License, Christian Gruen

Field Summary

Fields

Modifier and Type	Field and Description
protected TokenList	cache Cached results.
protected java.io.OutputStream	out Client output stream.
protected int	pos Cache pointer.

Constructor Summary

Constructors

Constructor and Description
Query()

Method Summary

Methods

Modifier and Type	Method and Description
void	bind(java.lang.String n, java.lang.Object v) Binds a value to an external variable.
abstract void	bind(java.lang.String n, java.lang.Object v, java.lang.String t) Binds a value with an optional type to an external variable.
protected abstract void	cache() Caches the query result.
protected void	cache(java.io.InputStream is) Caches the incoming input.
abstract void	close() Closes the query.
void	context(java.lang.Object v) Binds a value to the context item.
abstract void	context(java.lang.Object v, java.lang.String t) Binds a value with an optional type to an external variable.
abstract java.lang.String	execute() Returns the complete result of the query.
abstract java.lang.String	info() Returns query info.
boolean	more() Returns true if more items are available.
java.lang.String	next() Returns the next item of the query.
abstract java.lang.String	options() Returns the serialization options.
abstract boolean	updating() Returns true if the query may perform updates.

Methods inherited from class java.lang.Object

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

Field Detail

out

protected java.io.OutputStream out

Client output stream.

cache

protected TokenList cache

Cached results.

pos

protected int pos

Cache pointer.

Constructor Detail

Query

public Query()

Method Detail

bind

public final void bind(java.lang.String n,
        java.lang.Object v)
                throws java.io.IOException

Binds a value to an external variable.

Parameters:

n - name of variable

v - value to be bound

Throws:

java.io.IOException - I/O exception

bind

public abstract void bind(java.lang.String n,
        java.lang.Object v,
        java.lang.String t)
                   throws java.io.IOException

Binds a value with an optional type to an external variable.

Parameters:

n - name of variable

v - value to be bound

t - data type (may be null)

Throws:

java.io.IOException - I/O exception

context

public final void context(java.lang.Object v)
                   throws java.io.IOException

Binds a value to the context item.

Parameters:

v - value to be bound

Throws:

java.io.IOException - I/O exception

context

public abstract void context(java.lang.Object v,
           java.lang.String t)
                      throws java.io.IOException

Binds a value with an optional type to an external variable.

Parameters:

v - value to be bound

t - data type (may be null)

Throws:

java.io.IOException - I/O exception

more

public boolean more()
             throws java.io.IOException

Returns true if more items are available.

Returns:

result of check

Throws:

java.io.IOException - I/O exception

cache

protected abstract void cache()
                       throws java.io.IOException

Caches the query result.

Throws:

java.io.IOException - I/O exception

next

public final java.lang.String next()
                            throws java.io.IOException

Returns the next item of the query.

Returns:

item string or null.

Throws:

java.io.IOException - I/O exception

cache

protected void cache(java.io.InputStream is)
              throws java.io.IOException

Caches the incoming input.

Parameters:

is - input stream

Throws:

java.io.IOException - I/O exception

execute

public abstract java.lang.String execute()
                                  throws java.io.IOException

Returns the complete result of the query.

Returns:

item string or null.

Throws:

java.io.IOException - I/O exception

options

public abstract java.lang.String options()
                                  throws java.io.IOException

Returns the serialization options.

Returns:

serialization options.

Throws:

java.io.IOException - I/O exception

updating

public abstract boolean updating()
                          throws java.io.IOException

Returns true if the query may perform updates.

Returns:

updating flag

Throws:

java.io.IOException - I/O exception

info

public abstract java.lang.String info()
                               throws java.io.IOException

Returns query info.

Returns:

query info

Throws:

java.io.IOException - I/O exception

close

public abstract void close()
                    throws java.io.IOException

Closes the query.

Throws:

java.io.IOException - I/O exception