Use the overloaded methods to specify the encoding
when telling drools about the XLS:
public interface KieResources extends Service {
Resource newUrlResource(URL url);
Resource newUrlResource(URL url,
String encoding);
Resource newUrlResource(String path);
Resource newUrlResource(String path,
String encoding);
Resource newFileSystemResource(File file);
Resource newFileSystemResource(File file,
String encoding);
...
}
If you don't do that, it will use the default encoding of the Java platform which uses the default of the operation system (UTF-8 on linux, windows-1252 on a French Windows machine, ...)