Re: [basex-talk] How to call XQuery function from Java?

Hi Paul.

Is it possible for a Java function called from XQuery in BaseX to call back to an XQuery function that's passed to it in BaseX?

Your solution looks fine; it can be further simplified:

package my;

import org.basex.query.*; import org.basex.query.value.*; import org.basex.query.value.item.*;

public class Module extends QueryModule { public Value invoke(FuncItem func) throws Exception { return func.invoke(queryContext, null, Str.get("Java")); } }

Best, Christian

I haven't been able to find any documentation or examples of this. I got the following example to work, but it doesn't feel right. Is there a better way that might take advantage of the automatic type conversions BaseX performs and doesn't require calling something named "...Internal"?

Thanks!

---

xquery

import module namspace java = 'java:my.Module;

declare function local:hello($p as xs:string) as xs:string { concat("Hello ", $p) };

java:invoke(local:hello#1)

---

Java

package my;

import java.io.UnsupportedEncodingException;

import org.basex.query.QueryException; import org.basex.query.QueryModule; import org.basex.query.value.type.AtomType; import org.basex.query.value.item.FuncItem; import org.basex.query.value.item.Str; import org.basex.query.value.Value; import org.basex.util.InputInfo;

public class Module extends QueryModule { public String invoke(final FuncItem func) throws UnsupportedEncodingException, QueryException { InputInfo ii = new InputInfo("my.Module.invoke", 0, 0); String s = "Java"; Str p1 = new Str(s.getBytes("UTF-8"), AtomType.STRING); Value[] args = new Value[] {p1}; String r = (String) func.invokeInternal(queryContext, ii, args).toJava();

return r;

} }