Changeset 2708

Timestamp:

02/17/05 15:26:49 (8 years ago)

Author:

hauma

Message:

Proof of concept for a JavaParty RMI server (ticket:224)

• Use the JavaParty transparency layer within the middle-tier PartyServer without making it part of the distributed environment. This works along the lines of the "-frontend" switch for regular JavaParty applications (with GUI).

Location:

trunk/jp/src/jp/lang

Files:

• PartyClient.java (modified) (1 diff)
• PartyServer.java (modified) (2 diffs)
• PartyWorker.java (modified) (2 diffs)

trunk/jp/src/jp/lang/PartyClient.java

@@ -4 +4 @@
 import java.rmi.registry.LocateRegistry;
 
-
+/** The client-tier application. */
 public class PartyClient {
     public static void main(String[] args) throws Exception {

trunk/jp/src/jp/lang/PartyServer.java

@@ -1 +1 @@
 package jp.lang;
 
+import jp.lang.ApplicationContext;
+import jp.lang.Configuration;
+import jp.lang.DistributedRuntime;
+import jp.lang.RuntimeEnvironment;
+import jp.lang.RuntimeManager;
+
 import jp.lang.PartyConfig;
-import jp.lang.Configuration;
-import jp.lang.RuntimeManager;
-import jp.lang.ApplicationContext;
 
 
+/** 
+ * The middle-tier server. Instances of this class live outside the
+ * distributed JavaParty environment and mediate between client-tier
+ * applications and server-tier compute objects.
+ */
 public class PartyServer extends java.rmi.server.UnicastRemoteObject implements PartyServer_intf {
     PartyConfig config;
-    RuntimeManager rm;
-    ApplicationContext context;
     int size;
     int nr = 0;
 
-    PartyServer(PartyConfig config, RuntimeManager rm) throws java.rmi.RemoteException, jp.lang.ConfigurationException {
+    PartyServer(PartyConfig config) throws java.rmi.RemoteException {
         this.config = config;
-        this.rm = rm;
-        this.context = rm.allocateContext();
-        this.size = context.getMachineCnt();
+        this.size = jp.lang.DistributedRuntime.getMachineCnt();
     }
 
-    public void gotoParty() throws ClassNotFoundException, java.rmi.RemoteException {
-        try {
-            if (config.verbose) System.err.println("Request for party");
+    /** 
+     * The RMI-style remote method declared in {@link
+     * PartyServer_intf}. 
+     */
+    public void gotoParty() {
+        if (config.verbose) System.err.println("Request for party");
 
-            rm.getClassObject("jp.lang.PartyWorker");
+        // Create a new worker object within the cluster. This uses
+        // regular JavaParty-style remote object creation.
+        PartyWorker worker = new PartyWorker(nr++);
 
-            if (config.verbose) System.err.println("Loaded worker class");
+        if (config.verbose) System.err.println("Starting party");
 
-            // Lookup the workers class.
-            PartyWorker_class_intf workerClassIntf = (PartyWorker_class_intf)
-                rm.getConstructorObject("jp.lang.PartyWorker", (nr++) % size);
-
-            if (config.verbose) System.err.println("Creating PartyWorker");
-
-            // Create a new worker.
-            PartyWorker_instance_intf worker;
-
-            // The code is different for JavaParty/RMI and JavaParty/KaRMI:
-            // <%ifeq(@rmi.package@, uka.karmi.rmi)>
-
-            // In JavaParty/KaRMI, the per class factory method
-            // returns a bare remote reference instead of a stub
-            // object.
-            uka.karmi.rmi.server.UnicastRemoteClientRef workerRef = 
-                (uka.karmi.rmi.server.UnicastRemoteClientRef) workerClassIntf._new(nr);
-
-            // Construct stub from worker reference locally.
-            worker = new PartyWorker_instance_impl_KStub();
-            ((PartyWorker_instance_impl_KStub) worker)._KARMI_setRemoteClientRef(workerRef);
-
-            // <%>
-
-            worker = (PartyWorker_instance_intf) workerClassIntf._new(nr);
-            // <%/ifeq>
-
-
-            if (config.verbose) System.err.println("Starting party");
-
-            // Start the work at the party
-            worker.party();
-        } catch (@rmi.package@.RemoteException ex) {
-            // Translate the exceptions.
-            throw new java.rmi.RemoteException(ex.getMessage());
-        } catch (jp.lang.MovedException ex) {
-            // Of course, this should not happen.
-            throw new java.rmi.RemoteException("worker escaped!");
-        }
+        // Invoke the compute method on a server object within the
+        // distributed JavaParty environment.
+        worker.party();
     }
 
+    /** 
+     * The main method of the middle-tier server. Contacts the
+     * JavaParty environment and exports a regular RMI-style server
+     * object to a local registry.
+     */
     public static void main(String[] args) throws Exception {
         PartyConfig config = new PartyConfig();
@@ -77 +55 @@
             new Configuration(config.debug, config.host, config.port, config.code);
 
-        if (config.verbose) System.err.println("Lookup RuntimeManager");
+        if (config.verbose) System.err.println("Looking up the RuntimeManager");
         RuntimeManager rm = configuration.getRuntimeManager(/*timeout=forever*/ 0);
 
-        if (config.verbose) System.err.println("Creating local registry");
+        // Initialize the JavaParty transparency layer (outside the
+        // distributed runtime environment). This is the trick used to
+        // get the "-frontend" switch in jpinvite normally to
+        // work. The current virtual machine can use all services of
+        // the connected runtime environment without being part of it
+        // itself.
+        ApplicationContext context = rm.allocateContext();
+        jp.lang.RuntimeEnvironment.init(rm, context);
+
+        if (config.verbose) System.err.println("Creating the local RMI registry");
         java.rmi.registry.Registry registry = 
             java.rmi.registry.LocateRegistry.createRegistry(
                 java.rmi.registry.Registry.REGISTRY_PORT);
         
-        if (config.verbose) System.err.println("Binding PartyServer");
-        registry.bind("PartyServer", new PartyServer(config, rm));
+        if (config.verbose) System.err.println("Binding the PartyServer in the registry");
+        registry.bind("PartyServer", new PartyServer(config));
     }
 }

trunk/jp/src/jp/lang/PartyWorker.java

@@ -6 +6 @@
 
 
+/** 
+ * The server-tier compute class. Instances of this class reside in
+ * the distributed JavaParty environment.
+ */
 public remote class PartyWorker {
     int nr;
@@ -13 +17 @@
     }
 
+    /** 
+     * A JavaParty-style transparent remote method. This method is
+     * invoked from the client-tier application in {@link PartyClient}
+     * throug the middle-tier {@link PartyServer}.
+     */
     public void party() {
         System.out.println("party#" + nr + "@work");