dumping threads in code on Java8+

DiagnosticCommandMBeanHelper.java

import javax.management.DynamicMBean;
import javax.management.MBeanException;
import javax.management.ReflectionException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class DiagnosticCommandMBeanHelper {

    public static String threadPrint() throws ReflectionException, MBeanException {
        try {
            return callDiagnosticsMethod("threadPrint");
        } catch (ClassNotFoundException e) {
            throw new ReflectionException(e);
        } catch (NoSuchMethodException e) {
            throw new ReflectionException(e);
        } catch (InvocationTargetException e) {
            throw new ReflectionException(e);
        } catch (IllegalAccessException e) {
            throw new ReflectionException(e);
        }
    }

    private static String callDiagnosticsMethod(String actionName) throws MBeanException, ReflectionException, ClassNotFoundException, NoSuchMethodException, InvocationTargetException, IllegalAccessException {
        String[] emptyStringArgs = {};
        Object[] dcmdArgs = {emptyStringArgs};
        String[] signature = {String[].class.getName()};

        Class<?> clazz = Class.forName("sun.management.ManagementFactoryHelper");
        Method method = clazz.getMethod("getDiagnosticCommandMBean");

        DynamicMBean dcmd = (DynamicMBean)method.invoke(null);
        return (String)dcmd.invoke(actionName, dcmdArgs, signature);
    }
}