/*------------------------------------------------------------------------------
Name: RmiDriver.java
Project: xmlBlaster.org
Copyright: xmlBlaster.org, see xmlBlaster-LICENSE file
Comment: RmiDriver class to invoke the xmlBlaster server using RMI.
Version: $Id: RmiDriver.java 15205 2006-06-29 17:25:12Z ruff $
------------------------------------------------------------------------------*/
package org.xmlBlaster.protocol.rmi;
import java.util.logging.Logger;
import java.util.logging.Level;
import org.xmlBlaster.util.Global;
import org.xmlBlaster.util.XmlBlasterException;
import org.xmlBlaster.util.def.Constants;
import org.xmlBlaster.util.def.ErrorCode;
import org.xmlBlaster.util.XmlBlasterSecurityManager;
import org.xmlBlaster.engine.qos.AddressServer;
import org.xmlBlaster.protocol.I_Authenticate;
import org.xmlBlaster.protocol.I_XmlBlaster;
import org.xmlBlaster.protocol.I_Driver;
import java.rmi.RemoteException;
import java.rmi.Naming;
import java.rmi.AlreadyBoundException;
/**
* RmiDriver class to invoke the xmlBlaster server using RMI.
* <p />
* Design issues:
* <p />
* How to identify the calling client.
* <p />
* How does RMI handle incoming requests?<br />
* Is it a worker thread model, or a 1 client/one thread
* model, or 1 worker thread per RMI call?
* When a call comes in a random thread is taken from a pool.<br />
* According to the rmi specs "A method dispatched by the RMI runtime to a
* remote object implementation (a server) may or may not execute in a
* separate thread. Some calls originating from the same client virtual
* machine will execute in the same thread; some will execute in different
* threads. Calls originating from different client virtual machines will
* execute in different threads. Other than this last case of different
* client virtual machines, the RMI runtime makes no guarantees with
* respect to mapping remote object invocations to threads. "<br />
* <p />
* Possible soultions:
* <ul>
* <li>Give each client its own remote object to call<br />
* We can implicitly identiofy the client, but we
* will have problems with many connecting clients
* because of the 1-1 mapping between threads and sockets.
* </li>
* <li>Pass the sessionId with each method call<br />
* Implicitly this will be one server object serving all clients
* It is not very smart
* </li>
* <li>Hack rmic to automatically pass a client id</li>
* </ul>
* We will choose the second solution (pass the sessionId).
* <p />
* RMI has not fine controlled policy like the CORBA POA!
* <p />
* A rmi-registry server is created automatically, if there is running already one, that is used.<br />
* You can specify another port or host to create/use a rmi-registry server:
* <pre>
* -plugin/rmi/registryPort Specify a port number where rmiregistry listens.
* Default is port 1099, the port 0 switches this feature off.
* -plugin/rmi/hostname Specify a hostname where rmiregistry runs.
* Default is the localhost.
* </pre>
* <p />
* Invoke options: <br />
* <pre>
* java -Djava.rmi.server.codebase=file:///${XMLBLASTER_HOME}/classes/ \
* -Djava.security.policy=${XMLBLASTER_HOME}/config/xmlBlaster.policy \
* -Djava.rmi.server.hostname=hostname.domainname
* MyApp -plugin/rmi/registryPort 2078
* </pre>
* Another option is to include the directory of xmlBlaster.policy into
* your CLASSPATH.
*
* @see <a href="http://www.xmlBlaster.org/xmlBlaster/doc/requirements/protocol.rmi.html">The RMI requirement</a>
* @see <a href="http://java.sun.com/products/jdk/1.2/docs/guide/rmi/faq.html" target="others">RMI FAQ</a>
* @see <a href="http://archives.java.sun.com/archives/rmi-users.html" target="others">RMI USERS</a>
*/
public class RmiDriver implements I_Driver
{
private String ME = "RmiDriver";
private Global glob = null;
private static Logger log = Logger.getLogger(RmiDriver.class.getName());
/** XmlBlaster RMI registry listen port is 1099, to access for bootstrapping */
public static final int DEFAULT_REGISTRY_PORT = 1099;
/** The singleton handle for this xmlBlaster server */
private I_Authenticate authenticate = null;
/** The singleton handle for this xmlBlaster server */
private I_XmlBlaster xmlBlasterImpl = null;
/** The RMI implementation, which delegates to authenticate */
private AuthServerImpl authRmiServer = null;
/** The name for the RMI registry */
private String authBindName = null;
/** The RMI implementation, which delegates to xmlBlaster server */
private XmlBlasterImpl xmlBlasterRmiServer = null;
/** The name for the RMI registry */
private String xmlBlasterBindName = null;
private boolean isActive = false;
/** The protocol plugin configuration */
private AddressServer addressServer;
/** Get a human readable name of this driver */
public String getName() {
return ME;
}
/**
* Access the xmlBlaster internal name of the protocol driver.
* @return "RMI"
*/
public String getProtocolId() {
return "RMI";
}
/** Enforced by I_Plugin */
public String getType() {
return getProtocolId();
}
/** Enforced by I_Plugin */
public String getVersion() {
return "1.0";
}
/**
* This method is called by the PluginManager (enforced by I_Plugin).
* @see org.xmlBlaster.util.plugin.I_Plugin#init(org.xmlBlaster.util.Global,org.xmlBlaster.util.plugin.PluginInfo)
*/
public void init(org.xmlBlaster.util.Global glob, org.xmlBlaster.util.plugin.PluginInfo pluginInfo)
throws XmlBlasterException {
this.glob = glob;
this.ME = "RmiDriver" + this.glob.getLogPrefixDashed();
org.xmlBlaster.engine.ServerScope engineGlob = (org.xmlBlaster.engine.ServerScope)glob.getObjectEntry(Constants.OBJECT_ENTRY_ServerScope);
if (engineGlob == null)
throw new XmlBlasterException(this.glob, ErrorCode.INTERNAL_UNKNOWN, ME + ".init", "could not retreive the ServerNodeScope. Am I really on the server side ?");
try {
this.authenticate = engineGlob.getAuthenticate();
if (this.authenticate == null) {
throw new XmlBlasterException(this.glob, ErrorCode.INTERNAL_UNKNOWN, ME + ".init", "authenticate object is null");
}
I_XmlBlaster xmlBlasterImpl = this.authenticate.getXmlBlaster();
if (xmlBlasterImpl == null) {
throw new XmlBlasterException(this.glob, ErrorCode.INTERNAL_UNKNOWN, ME + ".init", "xmlBlasterImpl object is null");
}
init(glob, new AddressServer(glob, getType(), glob.getId(), pluginInfo.getParameters()), this.authenticate, xmlBlasterImpl);
activate();
}
catch (XmlBlasterException ex) {
throw ex;
}
catch (Throwable ex) {
throw new XmlBlasterException(this.glob, ErrorCode.INTERNAL_UNKNOWN, ME + ".init", "init. Could'nt initialize the driver.", ex);
}
}
/**
* Get the address how to access this driver.
* @return "rmi://www.mars.universe:1099/I_AuthServer"
*/
public String getRawAddress() {
return authBindName;
}
/**
* Start xmlBlaster RMI access.
* @param glob Global handle to access logging, property and commandline args
*/
private synchronized void init(Global glob, AddressServer addressServer, I_Authenticate authenticate, I_XmlBlaster xmlBlasterImpl) throws XmlBlasterException
{
this.authenticate = authenticate;
this.xmlBlasterImpl = xmlBlasterImpl;
this.addressServer = addressServer;
XmlBlasterSecurityManager.createSecurityManager(glob);
// plugin/rmi/registryPort
int registryPort = addressServer.getEnv("registryPort", DEFAULT_REGISTRY_PORT).getValue(); // default xmlBlaster RMI publishing port is 1099
String hostname = addressServer.getEnv("hostname", glob.getLocalIP()).getValue();
try {
if (registryPort > 0) {
// Start a 'rmiregistry' if desired
try {
java.rmi.registry.LocateRegistry.createRegistry(registryPort);
log.info("Started RMI registry on port " + registryPort);
} catch (java.rmi.server.ExportException e) {
// Try to bind to an already running registry:
try {
java.rmi.registry.LocateRegistry.getRegistry(hostname, registryPort);
log.info("Another rmiregistry is running on port " + DEFAULT_REGISTRY_PORT +
" we will use this one. You could change the port with e.g. '-plugin/rmi/registryPort 1122' to run your own rmiregistry.");
}
catch (RemoteException e2) {
String text = "Port " + DEFAULT_REGISTRY_PORT + " is already in use, but does not seem to be a rmiregistry. Please can change the port with e.g. -plugin/rmi/registryPortCB=1122 : " + e.toString();
log.severe(text);
throw new XmlBlasterException(ME, text);
}
}
}
String prefix = "rmi://";
authBindName = prefix + hostname + ":" + registryPort + "/I_AuthServer";
authBindName = addressServer.getEnv("AuthServerUrl", authBindName).getValue();
xmlBlasterBindName = prefix + hostname + ":" + registryPort + "/I_XmlBlaster";
xmlBlasterBindName = addressServer.getEnv("XmlBlasterUrl", xmlBlasterBindName).getValue();
} catch (Exception e) {
e.printStackTrace();
throw new XmlBlasterException("InitRmiFailed", "Could not initialize RMI registry: " + e.toString());
}
if (log.isLoggable(Level.FINE)) log.fine("Initialized RMI server");
}
/**
* Activate xmlBlaster access through this protocol.
*/
public synchronized void activate() throws XmlBlasterException {
if (log.isLoggable(Level.FINER)) log.finer("Entering activate");
try {
authRmiServer = new AuthServerImpl(glob, this.addressServer, this.authenticate, xmlBlasterImpl);
xmlBlasterRmiServer = new XmlBlasterImpl(glob, this.addressServer, xmlBlasterImpl);
}
catch (RemoteException e) {
log.severe(e.toString());
throw new XmlBlasterException("RmiDriverFailed", e.toString());
}
bindToRegistry();
isActive = true;
log.info("Started successfully RMI driver.");
}
/**
* Deactivate xmlBlaster access (standby), no clients can connect.
*/
public synchronized void deActivate() throws XmlBlasterException {
if (log.isLoggable(Level.FINER)) log.finer("Entering deActivate");
try {
if (authBindName != null) {
Naming.unbind(authBindName);
}
// force shutdown, even if we still have calls in progress:
java.rmi.server.UnicastRemoteObject.unexportObject(authRmiServer, true);
} catch (Exception e) {
log.warning("Can't shutdown authentication server: " + e.toString());
}
try {
if (xmlBlasterBindName != null) Naming.unbind(xmlBlasterBindName);
// force shutdown, even if we still have calls in progress:
java.rmi.server.UnicastRemoteObject.unexportObject(xmlBlasterRmiServer, true);
} catch (Exception e) {
log.warning("Can't shutdown xmlBlaster server: " + e.toString());
}
isActive = false;
log.info("RMI deactivated, no client access possible.");
}
/**
* Instructs RMI to shut down.
*/
public void shutdown() throws XmlBlasterException {
if (log.isLoggable(Level.FINE)) log.fine("Shutting down RMI driver ...");
if (isActive) {
try {
deActivate();
} catch (XmlBlasterException e) {
log.severe(e.toString());
}
}
authBindName = null;
log.info("RMI driver stopped, naming entries released.");
}
/**
* Publish the RMI xmlBlaster server to rmi registry.
* <p />
* The bind name is typically "rmi://localhost:1099/xmlBlaster"
* @exception XmlBlasterException
* RMI registry error handling
*/
private void bindToRegistry() throws XmlBlasterException
{
if (log.isLoggable(Level.FINER)) log.finer("bindToRegistry() ...");
// Publish RMI based xmlBlaster server ...
try {
Naming.bind(authBindName, authRmiServer);
log.info("Bound authentication RMI server to registry with name '" + authBindName + "'");
} catch (AlreadyBoundException e) {
try {
Naming.rebind(authBindName, authRmiServer);
log.warning("Removed another entry while binding authentication RMI server to registry with name '" + authBindName + "'");
}
catch(Exception e2) {
if (log.isLoggable(Level.FINE)) log.fine("RMI registry of '" + authBindName + "' failed: " + e2.toString());
throw new XmlBlasterException(ME+".RmiRegistryFailed", "RMI registry of '" + authBindName + "' failed: " + e2.toString());
}
} catch (java.rmi.NoSuchObjectException e) { // 'rmi://noty:7904/I_AuthServer': authRmiServer -> no such object in table
if (log.isLoggable(Level.FINE)) log.fine("RMI registry of '" + authBindName + "' authRmiServer=" + authRmiServer + " failed: " + e.getMessage());
throw new XmlBlasterException(glob, ErrorCode.RESOURCE_CONFIGURATION, ME+".RmiRegistryFailed",
"RMI registry of '" + authBindName + "' failed, probably another server instance is running already (implementation to handle this is missing): " + e.toString());
} catch (Throwable e) {
if (log.isLoggable(Level.FINE)) log.fine("RMI registry of '" + authBindName + "' failed: " + e.getMessage());
throw new XmlBlasterException(glob, ErrorCode.RESOURCE_CONFIGURATION, ME+".RmiRegistryFailed",
"RMI registry of '" + authBindName + "' failed: ", e);
}
try {
Naming.bind(xmlBlasterBindName, xmlBlasterRmiServer);
log.info("Bound xmlBlaster RMI server to registry with name '" + xmlBlasterBindName + "'");
} catch (AlreadyBoundException e) {
try {
Naming.rebind(xmlBlasterBindName, xmlBlasterRmiServer);
log.warning("Removed another entry while binding xmlBlaster RMI server to registry with name '" + xmlBlasterBindName + "'");
} catch (Exception e2) {
log.severe("RMI registry of '" + xmlBlasterBindName + "' failed: " + e.toString());
throw new XmlBlasterException(glob, ErrorCode.RESOURCE_CONFIGURATION, ME+".RmiRegistryFailed", "RMI registry of '" + xmlBlasterBindName + "' failed: " + e.toString());
}
} catch (Throwable e) {
log.severe("RMI registry of '" + xmlBlasterBindName + "' failed: " + e.toString());
throw new XmlBlasterException(glob, ErrorCode.RESOURCE_CONFIGURATION, ME+".RmiRegistryFailed", "RMI registry of '" + xmlBlasterBindName + "' failed", e);
}
}
/**
* Command line usage.
*/
public String usage()
{
String text = "\n";
text += "RmiDriver options:\n";
text += " -plugin/rmi/registryPort\n";
text += " Specify a port number where rmiregistry listens.\n";
text += " Default is port "+DEFAULT_REGISTRY_PORT+", the port 0 switches this feature off.\n";
text += " -plugin/rmi/hostname\n";
text += " Specify a hostname where rmiregistry runs.\n";
text += " Default is the localhost.\n";
text += "\n";
return text;
}
}