11 Replies Latest reply on Aug 6, 2007 6:35 AM by Newsgroup_User

    Simple RPC with RemoteObject


      I am a newbie and I am trying a simple application to test RPC using RemoteObject. My application takes a name from a text input field and prints the welcome greeting in a text area.

      The method to execute in my RemoteObject is a goofy method that takes a person's name and returns the String welcoming the person.

      Here is the method.

      package rpc.playerinfo;
      public class PlayerService {
      public String printThis(String name) {
      return "Welcome to " + name;

      I've added a destination representing this remote object in the remote-config.xml file.
      <destination id="PlayerDB">

      My MXML code is given below :

      <?xml version="1.0" encoding="utf-8"?>
      <mx:Application xmlns:mx=" http://www.adobe.com/2006/mxml" layout="absolute">
      import rpc.playerinfo.*;

      private function fillTxt(b: String):void{
      mainTxt.text = b;

      <mx:RemoteObject id="play" destination="PlayerDB">
      <mx:method name="printThis" concurrency="last" result="fillTxt(event.result as String)"/>

      <mx:Panel title="Get Player">
      <mx:TextArea id = "mainTxt"/> <!-- This is where the output goes-->
      <mx:TextInput id="txtNumber"/> <!-- This is where the text is input-->
      <mx:Button label="i like to print" click="play.printThis(txtNumber.text)" /> <--Call the remote object here -->

      When I try to run it, I get the following error, when I click the button.

      [RPC Fault faultString="[MessagingError message='Unknown destination 'PlayerDB'.']" faultCode="InvokeFailed" faultDetail="Couldn't establish a connection to 'PlayerDB'"]
      at mx.rpc::AbstractInvoker/ http://www.adobe.com/2006/flex/mx/internal::invoke()
      at mx.rpc.remoting.mxml::Operation/ http://www.adobe.com/2006/flex/mx/internal::invoke()
      at mx.rpc.remoting::Operation/send()
      at Function/ http://adobe.com/AS3/2006/builtin::apply()
      at mx.rpc.remoting.mxml::Operation/send()
      at Function/ http://adobe.com/AS3/2006/builtin::apply()
      at mx.rpc::AbstractService/ http://www.adobe.com/2006/actionscript/flash/proxy::callProperty()
      at RPCDataService/___Button1_click()

      Please help this newbie. Thank you.
        • 1. Re: Simple RPC with RemoteObject
          Mete Atamel Level 1
          Hi, I tried the same example and it worked for me. Are you sure you're editing the right remoting-config.xml ?
          • 2. Re: Simple RPC with RemoteObject
            arkcto Level 1
            Thanks matamel,

            I don't know how it can work on your computer and not on mine. Yes, I am modifying the right configuration files.

            My full remoting-config file looks like this :

            <?xml version="1.0" encoding="UTF-8"?>
            <service id="remoting-service"

            <adapter-definition id="java-object" class="flex.messaging.services.remoting.adapters.JavaAdapter" default="true"/>

            <channel ref="my-amf"/>

            <destination id="PlayerDB">


            Also, my web.xml is pretty empty. Anything need to be there ?

            <?xml version="1.0" encoding="ISO-8859-1"?>
            <!DOCTYPE web-app
            PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
            " http://java.sun.com/dtd/web-app_2_3.dtd">
            <!-- BalancerFilter definition -->

            Also, I have two web applications - Flex and rpcdataservice. Inside my rpcdataservice I have a web-inf folder, inside which I have another flex subdirectory. I am modifying the remote-config.xml file in my flex subdirectory inside my rpcdataservice web application. I am NOT modifying it in the flex web application (The Flex root).

            Should I have a correponding actionscript file for my Java class ? I was under the assumption that those are required only if I am using them as data types. Here the return type is just a String.

            Thanks for your help.
            • 3. Re: Simple RPC with RemoteObject
              Mete Atamel Level 1
              No, you don't need need Actionscipt files in this case. Your remoting-config.xml file is correct but maybe your application tries to pick remoting-config.xml from the Flex folder? Why don't you define PlayerDB in WEB-INF/ of Flex folder as well and see if that makes a difference?
              • 4. Re: Simple RPC with RemoteObject
                arkcto Level 1
                Tried everything, doesn't work.

                Even removed flex and flex-admin webapps from Tomcat. Just have rpcdataservice webapp and inside that the Flex subfolder with the right configuration files.

                Also, I used the build.bat (got it from flex samples) to build the .swf file from .mxml file.

                @echo off
                SET OPTS=-use-network=false
                for /R . %%f in (*.mxml) do ..\..\bin\mxmlc.exe %OPTS% "%%f"

                I'm sure this has nothing to do with it, but I tried everything else already

                Thanks Matamel.
                • 5. Re: Simple RPC with RemoteObject
                  Mete Atamel Level 1
                  Hmm. I don't know what could be the problem but these are some things I'd try myself:

                  1- Can you define and use the remote object from flex or flex-admin apps?
                  2- Can you use other types of destinations in rpcdataservice app? (look into messaging-config.xml, proxy-config.xml and data-management.xml config for other types of destinations)
                  • 6. Re: Simple RPC with RemoteObject
                    arkcto Level 1
                    And the plot thickens.

                    I removed flex, flex-admin directories, and kept just the rpcdataservice (my app) as the only webapp under Tomcat. What I see is that if I launch .mxml from the browser, it works, but when I launch the .swf file it complains about 'unknown destination'.

                    I compiled the .mxml into .swf frm command-line using the batch file I mentioned in the earlier message.

                    So .mxml works, but .swf doesn't work. Again I am launching both the files from the browser.

                    Thanks for your patience.
                    • 7. Re: Simple RPC with RemoteObject
                      Mete Atamel Level 1
                      What happens when you try to launch the flex-admin swf file (console.swf I think)? Do you get the same type of error?
                      • 8. Re: Simple RPC with RemoteObject
                        Mete Atamel Level 1
                        By the way, when you compile mxml yourself, make sure you use --compiler.services <path_to_services-config.xml>. This points the compiler to your services configuration file and that way all the destination information gets compiled into the swf.
                        • 9. Re: Simple RPC with RemoteObject
                          arkcto Level 1
                          >>By the way, when you compile mxml yourself, make sure you use --compiler.services <path_to_services-config.xml>.

                          That works - now .the swf and mxml both work.

                          Thanks so much for your help, matamel.
                          • 10. Re: Simple RPC with RemoteObject
                            hi arkcto ,. i also have same problem as well
                            i have created a Flex 2 application and compiled a some java class..
                            i was using remoteobj to connect those java class

                            but i also got this error
                            RPC Fault faultString="[MessagingError message='Unknown destination 'PlayerDB'.

                            so that , what can i do .. thank ..
                            • 11. Re: Simple RPC with RemoteObject
                              Level 7
                              Did you specify a -services command line argument for the compiler and set
                              its value to the path to your /WEB-INF/flex/services-config.xml file?