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 * Copyright (c) 2002, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package javax.management.remote.rmi;

import java.io.IOException;

import java.rmi.NoSuchObjectException;

import java.rmi.Remote;

import java.rmi.RemoteException;

import java.rmi.server.RMIClientSocketFactory;

import java.rmi.server.RMIServerSocketFactory;

import java.rmi.server.UnicastRemoteObject;

import java.rmi.server.RemoteObject;

import java.util.Map;

import java.util.Collections;

import javax.security.auth.Subject;

import com.sun.jmx.remote.internal.rmi.RMIExporter;

import com.sun.jmx.remote.util.EnvHelp;

import java.io.ObjectStreamClass;

import java.lang.reflect.Method;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import sun.reflect.misc.ReflectUtil;

import sun.rmi.server.DeserializationChecker;

import sun.rmi.server.UnicastServerRef;

import sun.rmi.server.UnicastServerRef2;

/**

 * <p>An {@link RMIServer} object that is exported through JRMP and that

 * creates client connections as RMI objects exported through JRMP.

 * User code does not usually reference this class directly.</p>

 *

 * @see RMIServerImpl

 *

 * @since 1.5

 */

public class RMIJRMPServerImpl extends RMIServerImpl {

    private final ExportedWrapper exportedWrapper;

    /**

     * <p>Creates a new {@link RMIServer} object that will be exported

     * on the given port using the given socket factories.</p>

     *

     * @param port the port on which this object and the {@link

     * RMIConnectionImpl} objects it creates will be exported.  Can be

     * zero, to indicate any available port.

     *

     * @param csf the client socket factory for the created RMI

     * objects.  Can be null.

     *

     * @param ssf the server socket factory for the created RMI

     * objects.  Can be null.

     *

     * @param env the environment map.  Can be null.

     *

     * @exception IOException if the {@link RMIServer} object

     * cannot be created.

     *

     * @exception IllegalArgumentException if <code>port</code> is

     * negative.

     */

    public RMIJRMPServerImpl(int port,

                             RMIClientSocketFactory csf,

                             RMIServerSocketFactory ssf,

                             Map<String,?> env)

            throws IOException {

        super(env);

        if (port < 0)

            throw new IllegalArgumentException("Negative port: " + port);

        this.port = port;

        this.csf = csf;

        this.ssf = ssf;

        this.env = (env == null) ? Collections.<String, Object>emptyMap() : env;

        String[] credentialsTypes

                = (String[]) this.env.get(RMIConnectorServer.CREDENTIAL_TYPES);

        List<String> types = null;

        if (credentialsTypes != null) {

            types = new ArrayList<>();

            for (String type : credentialsTypes) {

                if (type == null) {

                    throw new IllegalArgumentException("A credential type is null.");

                }

                ReflectUtil.checkPackageAccess(type);

                types.add(type);

            }

        }

        exportedWrapper = types != null ?

                new ExportedWrapper(this, types) :

                null;

    }

    protected void export() throws IOException {

        if (exportedWrapper != null) {

            export(exportedWrapper);

        } else {

            export(this);

        }

    }

    private void export(Remote obj) throws RemoteException {

        final RMIExporter exporter =

            (RMIExporter) env.get(RMIExporter.EXPORTER_ATTRIBUTE);

        final boolean daemon = EnvHelp.isServerDaemon(env);

        if (daemon && exporter != null) {

            throw new IllegalArgumentException("If "+EnvHelp.JMX_SERVER_DAEMON+

                    " is specified as true, "+RMIExporter.EXPORTER_ATTRIBUTE+

                    " cannot be used to specify an exporter!");

        }

        if (daemon) {

            if (csf == null && ssf == null) {

                new UnicastServerRef(port).exportObject(obj, null, true);

            } else {

                new UnicastServerRef2(port, csf, ssf).exportObject(obj, null, true);

            }

        } else if (exporter != null) {

            exporter.exportObject(obj, port, csf, ssf);

        } else {

            UnicastRemoteObject.exportObject(obj, port, csf, ssf);

        }

    }

    private void unexport(Remote obj, boolean force)

            throws NoSuchObjectException {

        RMIExporter exporter =

            (RMIExporter) env.get(RMIExporter.EXPORTER_ATTRIBUTE);

        if (exporter == null)

            UnicastRemoteObject.unexportObject(obj, force);

        else

            exporter.unexportObject(obj, force);

    }

    protected String getProtocol() {

        return "rmi";

    }

    /**

     * <p>Returns a serializable stub for this {@link RMIServer} object.</p>

     *

     * @return a serializable stub.

     *

     * @exception IOException if the stub cannot be obtained - e.g the

     *            RMIJRMPServerImpl has not been exported yet.

     */

    public Remote toStub() throws IOException {

        if (exportedWrapper != null) {

            return RemoteObject.toStub(exportedWrapper);

        } else {

            return RemoteObject.toStub(this);

        }

    }

    /**

     * <p>Creates a new client connection as an RMI object exported

     * through JRMP. The port and socket factories for the new

     * {@link RMIConnection} object are the ones supplied

     * to the <code>RMIJRMPServerImpl</code> constructor.</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.

     *

     * @return the newly-created <code>RMIConnection</code>.

     *

     * @exception IOException if the new {@link RMIConnection}

     * object cannot be created or exported.

     */

    protected RMIConnection makeClient(String connectionId, Subject subject)

            throws IOException {

        if (connectionId == null)

            throw new NullPointerException("Null connectionId");

        RMIConnection client =

            new RMIConnectionImpl(this, connectionId, getDefaultClassLoader(),

                                  subject, env);

        export(client);

        return client;

    }

    protected void closeClient(RMIConnection client) throws IOException {

        unexport(client, true);

    }

    /**

     * <p>Called by {@link #close()} to close the connector server by

     * unexporting this object.  After returning from this method, the

     * connector server must not accept any new connections.</p>

     *

     * @exception IOException if the attempt to close the connector

     * server failed.

     */

    protected void closeServer() throws IOException {

        if (exportedWrapper != null) {

            unexport(exportedWrapper, true);

        } else {

            unexport(this, true);

        }

    }

    private final int port;

    private final RMIClientSocketFactory csf;

    private final RMIServerSocketFactory ssf;

    private final Map<String, ?> env;

    private static class ExportedWrapper implements RMIServer, DeserializationChecker {

        private final RMIServer impl;

        private final List<String> allowedTypes;

        private ExportedWrapper(RMIServer impl, List<String> credentialsTypes) {

            this.impl = impl;

            allowedTypes = credentialsTypes;

        }

        @Override

        public String getVersion() throws RemoteException {

            return impl.getVersion();

        }

        @Override

        public RMIConnection newClient(Object credentials) throws IOException {

            return impl.newClient(credentials);

        }

        @Override

        public void check(Method method, ObjectStreamClass descriptor,

                int paramIndex, int callID) {

            String type = descriptor.getName();

            if (!allowedTypes.contains(type)) {

                throw new ClassCastException("Unsupported type: " + type);

            }

        }

        @Override

        public void checkProxyClass(Method method, String[] ifaces,

                int paramIndex, int callID) {

            if (ifaces != null && ifaces.length > 0) {

                for (String iface : ifaces) {

                    if (!allowedTypes.contains(iface)) {

                        throw new ClassCastException("Unsupported type: " + iface);

                    }

                }

            }

        }

    }

}