dbus-java for Bluetooth HDP

Jim Connors james.connors at oracle.com
Thu Jul 14 14:21:46 PDT 2011


I'm trying to use dbus-java to communicate with a bluetooth Heathcare 
Device Profile (HDP) cpmpliant pulse oxymiter.  There has been some work 
demonstrating this capability with the Python dbus binding, but next to 
nothing on the Java front from what I see.  Not being a Python 
aficionado, trying to map the Python stuff over to Java isn't working 
out too well.   The example below attempts to make a remote invocation 
on a method called CreateApplication() as specified by the following 

package org.bluez;
import java.util.Map;
import org.freedesktop.dbus.DBusInterface;
import org.freedesktop.dbus.Variant;

public interface HealthManager extends DBusInterface
     public DBusInterface CreateApplication(Map<String,Variant> a);
     public void DestroyApplication(DBusInterface a);

The simple application below throws a DBusExecution exception when 
reaching the CreateApplication() method call:

package testhdp;

import java.util.Map;
import java.util.HashMap;
import org.freedesktop.DBus;
import org.freedesktop.dbus.DBusConnection;
import org.freedesktop.dbus.DBusInterface;
import org.freedesktop.dbus.Variant;
import org.freedesktop.dbus.UInt16;
import org.bluez.Manager;
import org.bluez.HealthManager;
import org.freedesktop.DBus.Introspectable;

class TestHDP {

     public static void main(String[] args) throws
             org.freedesktop.dbus.exceptions.DBusException {

         DBusConnection conn =

         DBus dbus = conn.getRemoteObject(
                 "org.freedesktop.DBus", "/org/freedesktop/DBus", 

         String ORG_BLUEZ = "org.bluez";
         System.out.print("Searching dbus.ListNames() return for " +
                 "\"" + ORG_BLUEZ + "\": ");
         String[] names = dbus.ListNames();
         boolean bluezFound = false;
         for (String name: names)
            if (name.equals(ORG_BLUEZ)) {
                bluezFound = true;
         if (bluezFound)
             System.out.println(ORG_BLUEZ + " found.");
             System.out.println(ORG_BLUEZ + " not found.");

         Manager m = (Manager) conn.getRemoteObject("org.bluez", "/",
         Map<String, Variant> props = m.GetProperties();

         HealthManager hm = (HealthManager) conn.getRemoteObject(
                 "org.bluez", "/org/bluez", HealthManager.class);

         Map<String, Variant> config = new HashMap<String, Variant>();
         config.put("DataType", new Variant<UInt16>(new UInt16(0x1004)));
         config.put("Role", new Variant<String>("Sink"));
         config.put("Description", new Variant<String>("Oximeter Sink"));

         DBusInterface app = hm.CreateApplication(config);


Output is as follows:

Searching dbus.ListNames() return for "org.bluez": org.bluez found.
org.bluez:/:interface org.bluez.Manager
org.bluez:/org/bluez:interface org.bluez.HealthManager
Exception in thread "main" 
org.freedesktop.dbus.exceptions.DBusExecutionException: Wrong return 
type (failed to de-serialize correct types: Failed to create proxy 
object for /org/bluez/health_app_30 exported by :1.51. Reason: Could not 
find an interface to cast to )
     at org.freedesktop.dbus.RemoteInvocationHandler.convertRV(Unknown 
     at org.freedesktop.dbus.RemoteInvocationHandler.invoke(Unknown Source)
     at $Proxy2.CreateApplication(Unknown Source)
     at testhdp.TestHDP.main(TestHDP.java:66)

Any guidance would be greatly appreciated.

Jim Connors

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