rmiserverimpl.java

java1.6众多例子参考

/*
 * @(#)RMIServerImpl.java	1.60 07/06/01
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.management.remote.rmi;

import com.sun.jmx.remote.internal.ArrayNotificationBuffer;
import com.sun.jmx.remote.internal.NotificationBuffer;
import com.sun.jmx.remote.security.JMXPluggableAuthenticator;
import com.sun.jmx.remote.util.ClassLogger;
import java.io.Closeable;
import java.io.IOException;
import java.lang.ref.WeakReference;
import java.rmi.Remote;
import java.rmi.server.RemoteServer;
import java.rmi.server.ServerNotActiveException;
import java.security.Principal;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.management.MBeanServer;
import javax.management.remote.JMXAuthenticator;
import javax.management.remote.JMXConnectorServer;
import javax.security.auth.Subject;

/**
 * <p>An RMI object representing a connector server.  Remote clients
 * can make connections using the {@link #newClient(Object)} method.  This
 * method returns an RMI object representing the connection.</p>
 *
 * <p>User code does not usually reference this class directly.
 * RMI connection servers are usually created with the class {@link
 * RMIConnectorServer}.  Remote clients usually create connections
 * either with {@link javax.management.remote.JMXConnectorFactory}
 * or by instantiating {@link RMIConnector}.</p>
 *
 * <p>This is an abstract class.  Concrete subclasses define the
 * details of the client connection objects, such as whether they use
 * JRMP or IIOP.</p>
 *
 * @since 1.5
 * @since.unbundled 1.0
 */
public abstract class RMIServerImpl implements Closeable, RMIServer {
    /**
     * <p>Constructs a new <code>RMIServerImpl</code>.</p>
     *
     * @param env the environment containing attributes for the new
     * <code>RMIServerImpl</code>.  Can be null, which is equivalent
     * to an empty Map.
     */
    public RMIServerImpl(Map<String,?> env) {
        this.env = (env == null) ? Collections.EMPTY_MAP : env;
    }

    void setRMIConnectorServer(RMIConnectorServer connServer)
	    throws IOException {
	this.connServer = connServer;
    }

    /**
     * <p>Exports this RMI object.</p>
     *
     * @exception IOException if this RMI object cannot be exported.
     */
    protected abstract void export() throws IOException;

    /**
     * Returns a remotable stub for this server object.
     * @return a remotable stub.
     * @exception IOException if the stub cannot be obtained - e.g the
     *            RMIServerImpl has not been exported yet.
     **/
    public abstract Remote toStub() throws IOException;  

    /**
     * <p>Sets the default <code>ClassLoader</code> for this connector
     * server. New client connections will use this classloader.
     * Existing client connections are unaffected.</p>
     *
     * @param cl the new <code>ClassLoader</code> to be used by this
     * connector server.
     *
     * @see #getDefaultClassLoader
     */
    public synchronized void setDefaultClassLoader(ClassLoader cl) {
        this.cl = cl;
    }

    /**
     * <p>Gets the default <code>ClassLoader</code> used by this connector
     * server.</p>
     *
     * @return the default <code>ClassLoader</code> used by this
     * connector server.</p>
     *
     * @see #setDefaultClassLoader
     */
    public synchronized ClassLoader getDefaultClassLoader() {
        return cl;
    }

    /**
     * <p>Sets the <code>MBeanServer</code> to which this connector
     * server is attached. New client connections will interact
     * with this <code>MBeanServer</code>. Existing client connections are
     * unaffected.</p>
     *
     * @param mbs the new <code>MBeanServer</code>.  Can be null, but
     * new client connections will be refused as long as it is.
     *
     * @see #getMBeanServer
     */
    public synchronized void setMBeanServer(MBeanServer mbs) {
        this.mbeanServer = mbs;
    }

    /**
     * <p>The <code>MBeanServer</code> to which this connector server
     * is attached.  This is the last value passed to {@link
     * #setMBeanServer} on this object, or null if that method has
     * never been called.</p>
     *
     * @return the <code>MBeanServer</code> to which this connector
     * is attached.
     *
     * @see #setMBeanServer
     */
    public synchronized MBeanServer getMBeanServer() {
        return mbeanServer;
    }

    public String getVersion() {
        // Expected format is: "protocol-version implementation-name"
        try {
            return "1.0 java_runtime_" +
                    System.getProperty("java.runtime.version");
        } catch (SecurityException e) {
            return "1.0 ";
        }
    }

    /**
     * <p>Creates a new client connection.  This method calls {@link
     * #makeClient makeClient} and adds the returned client connection
     * object to an internal list.  When this
     * <code>RMIServerImpl</code> is shut down via its {@link
     * #close()} method, the {@link RMIConnection#close() close()}
     * method of each object remaining in the list is called.</p>
     *
     * <p>The fact that a client connection object is in this internal
     * list does not prevent it from being garbage collected.</p>
     *
     * @param credentials this object specifies the user-defined
     * credentials to be passed in to the server in order to
     * authenticate the caller before creating the
     * <code>RMIConnection</code>.  Can be null.
     *
     * @return the newly-created <code>RMIConnection</code>.  This is
     * usually the object created by <code>makeClient</code>, though
     * an implementation may choose to wrap that object in another
     * object implementing <code>RMIConnection</code>.
     *
     * @exception IOException if the new client object cannot be
     * created or exported.
     *
     * @exception SecurityException if the given credentials do not allow
     * the server to authenticate the user successfully.
     *
     * @exception IllegalStateException if {@link #getMBeanServer()}
     * is null.
     */
    public RMIConnection newClient(Object credentials) throws IOException {
        return doNewClient(credentials);
    }

    /**
     * This method could be overridden by subclasses defined in this package
     * to perform additional operations specific to the underlying transport
     * before creating the new client connection.
     */
    RMIConnection doNewClient(Object credentials) throws IOException {
	final boolean tracing = logger.traceOn();

	if (tracing) logger.trace("newClient","making new client");

	if (getMBeanServer() == null)
	    throw new IllegalStateException("Not attached to an MBean server");

        Subject subject = null;
        JMXAuthenticator authenticator =
            (JMXAuthenticator) env.get(JMXConnectorServer.AUTHENTICATOR);
	if (authenticator == null) {
	    /*
	     * Create the JAAS-based authenticator only if authentication
	     * has been enabled
	     */
	    if (env.get("jmx.remote.x.password.file") != null ||
		env.get("jmx.remote.x.login.config") != null) {
		authenticator = new JMXPluggableAuthenticator(env);
	    }
	}
        if (authenticator != null) {
	    if (tracing) logger.trace("newClient","got authenticator: " +
			       authenticator.getClass().getName());
	    try {
		subject = authenticator.authenticate(credentials);
	    } catch (SecurityException e) {
		logger.trace("newClient", "Authentication failed: " + e);
		throw e;
	    }
        }

	if (tracing) {
	    if (subject != null) 
		logger.trace("newClient","subject is not null");
	    else logger.trace("newClient","no subject");
	}

	final String connectionId = makeConnectionId(getProtocol(), subject);

	if (tracing) 
	    logger.trace("newClient","making new connection: " + connectionId);

        RMIConnection client = makeClient(connectionId, subject);

	connServer.connectionOpened(connectionId, "Connection opened", null);

        dropDeadReferences();
        WeakReference wr = new WeakReference(client);
        synchronized (clientList) {
            clientList.add(wr);
        }

	if (tracing) 
	    logger.trace("newClient","new connection done: " + connectionId );

        return client;
    }

    /**
     * <p>Creates a new client connection.  This method is called by
     * the public method {@link #newClient(Object)}.</p>
     *
     * @param connectionId the ID of the new connection.  Every
     * connection opened by this connector server will have a
     * different ID.  The behavior is unspecified if this parameter is
     * null.
     *
     * @param subject the authenticated subject.  Can be null.
     *