On 08.07.25 12:51, Per Nyfelt wrote:
Hi,
I am trying to figure out a way to
use @GrabConfig(systemClassLoader=true) in a ScritpEngine (or
GroovyShell, does not matter.
The following script works without any problem using the groovy command
(.e.g `groovy sqltaskExample.groovy`):
@GrabConfig(systemClassLoader=true)
@Grab('com.h2database:h2:2.3.232')
import groovy.ant.AntBuilder
...
Calling that from java however does not work:, e.g.
public class ShellWithGrabSupport {
public static void main(String[] args)throws Exception {
GroovyScriptEngine gse =new GroovyScriptEngine(".");
gse.run("sqltaskExample.groovy",new Binding());
}
}
Results in "No Suitable classloader found for Grab"
...
// This mimics what the `groovy` CLI does
GroovyMain.main(new String[]{"sqltaskExample.groovy"});
All with the same result.
If you run the program using the groovy command or a shell then there is
a GroovyClassLoader involved can be used instead of the systemloader.
Basically since Java9 Java does not use a url class loader as system
loader anymore. Which means we cannot support systemClassLoader=true in
case there is no rescuing GroovyClassLoader
I use the following to bootstrap java:
gl="$GROOVY_HOME/lib"
v="4.0.27"
cp="$gl/groovy-$v.jar:$gl/groovy-ant-$v.jar:$gl/groovy-ant-$v.jar:$gl/ant-1.10.15.jar:\
$gl/ant-launcher-1.10.15.jar:$gl/ivy-2.5.3.jar"
java -cp"$cp" ShellWithGrabSupport.java
you could try using -Djava.system.class.loader=... to set a class loader
using the fully qualified name. It should be a URLClassloader or child
of it and I guess the class needs to be on the classpath as well
The alternative is using a small program to load the classpath and start
the program. In Groovy we are using RootLoader for this. Or you use
GroovyStarter
bye Jochen
