Java Bindings

The Java Binding query feature is an extensibility mechanism which allows direct calling of Java methods bound as XQuery functions and manipulation of wrapped Java objects. For using the Java Binding feature the user needs admin rights.
Please note that the namespace URI must be of the form java:fullyQualifiedClassName.
The following examples introduce the behavior.

This example uses the java Math class and returns the cosine of an angle:

declare namespace math = "java:java.lang.Math";
math:cos(xs:double(0))

Please Note: To call a method directly it has to be set as static in you java code.

The next example writes 256 bytes to the file output.txt. To call the write method of the FileWriter class, you have to pass a class instance as first argument:

declare namespace fw = "java:java.io.FileWriter";
 
let $file := fw:new('output.txt')
return (
  for $i in 0 to 255
  return fw:write($file, xs:int($i)),
  fw:close($file)
)

Note that we recommend to use XQuery expressions and functions whenever possible, as Java code cannot be pre-compiled by BaseX, and will most probably be evaluated slower than pure XQuery code.