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→Context-Awareness
* The namespace of the function name identifies the Java class.
* The local part of the name, which is rewritten to camel case, identifies a variable or function of that class.
* The middle dot character <code>·</code> ([http://www.fileformat.info/info/unicode/char/b7/index.htm (·/&#xB7;]</code>; , a valid character in XQuery names, but not in Java) can be used to append exact Java parameter types to the function name. Class types must be referenced by their full path.
{| class="wikitable"
|- valign="top"
| Variable
| <code>Q{java.lang.Integer}MIN_VALUE()</code>
| <code>[https://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html#MAX_VALUE Integer.MIN_VALUE]</code>
|- valign="top"
=Module Imports=
Java code can also be integrated accessed by ''importing'' classes as modules. A new instance of the addressed class is will be created, which can then be accessed referenced in the query body.
The following, (side-effecting ) example returns the number of distinct values added to a hash set (the . The boolean values returned by {{Code|set:add()}} will be swallowed):
<pre class="brush:xquery">
import module namespace set = "java:java.util.HashSet";
prof:void(
for $s in ("one", "two", "one")
</pre>
The advantages of this approach is that the execution of imported code classes is executed faster more efficient than the execution of instances that are created at runtime via {{Code|new()}}. A drawback is that no arguments can be passed on to the class constructor. As a consequence, the import will fail fails if the addressed class has no default constructor, but at least one constructor with arguments and no default constructor.
=Context-Awareness=
Java classes can be coupled even more closely to the BaseX core library.
If a class inherits the abstract [https://github.com/BaseXdb/basex/blob/master/basex-core/src/main/java/org/basex/query/QueryModule.java QueryModule] class, the two variables [https://github.com/BaseXdb/basex/blob/master/basex-core/src/main/java/org/basex/query/QueryContext.java queryContext] and [https://github.com/BaseXdb/basex/blob/master/basex-core/src/main/java/org/basex/query/StaticContext.java staticContext] get available, which provide access to the global and static context of a query. Additionally, the default properties of functions can be changed via annotations:
