org.basex.query

Class QueryModule

java.lang.Object

org.basex.query.QueryModule

public abstract class QueryModule
extends java.lang.Object

The XQuery import module statement can be used to import XQuery modules as well as Java instances, which will be treated as modules. Any class with a public, empty constructor can be imported as module.

If a class extends the QueryModule class, it inherits the context variable, which provides access to all properties of the current query. E.g., it provides access to the current context item or the static context of a query. Next, the following default properties of functions can be changed via annotations:

• Java functions can only be executed by users with ADMIN permissions. You may annotate a function with QueryModule.Requires(QueryModule.Permission) to also make it accessible to users with less privileges.
• Java code is treated as "non-deterministic", as its behavior cannot be predicted by the XQuery processor. You may annotate a function as QueryModule.Deterministic if you know that it will have no side-effects and will always yield the same result.
• Java code is treated as "context-independent". If a function accesses the specified context, it should be annotated as QueryModule.ContextDependent.
• Java code is treated as "focus-independent". If a function accesses the current context item, position or size, it should be annotated as QueryModule.FocusDependent.

Please visit our documentation to find more details on Packaging, Java Bindings and User Management. The XQuery 3.0 specification gives more insight into function properties.

Author:

BaseX Team 2005-12, BSD License, Christian Gruen

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	QueryModule.ContextDependent Java code is treated as "context-independent".
static interface	QueryModule.Deterministic Java code is treated as "non-deterministic", as its behavior cannot be predicted from the XQuery processor.
static interface	QueryModule.FocusDependent Java code is treated as "focus-independent".
static class	QueryModule.Permission Permission required to call a function.
static interface	QueryModule.Requires Java functions can only be executed by users with ADMIN permissions.

Field Summary

Fields

Modifier and Type	Field and Description
QueryContext	context Query context.

Constructor Summary

Constructors

Constructor and Description
QueryModule()

Method Summary

Methods inherited from class java.lang.Object

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

Field Detail

context

public QueryContext context

Query context.

Constructor Detail

QueryModule

public QueryModule()