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

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 * 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).

 *

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package com.sun.jdi.connect;

import java.util.Map;

import java.io.IOException;

import com.sun.jdi.VirtualMachine;

/**

 * A connector which listens for a connection initiated by a target VM.

 *

 * @author Gordon Hirsch

 * @since  1.3

 */

@jdk.Exported

public interface ListeningConnector extends Connector {

    /**

     * Indicates whether this listening connector supports multiple

     * connections for a single argument map. If so, a call to

     * {@link #startListening} may allow

     * multiple target VM to become connected.

     *

     * @return {@code true} if multiple connections are supported;

     * {@code false} otherwise.

     */

    boolean supportsMultipleConnections();

    /**

     * Listens for one or more connections initiated by target VMs.

     * The connector uses the given argument map

     * in determining the address at which to listen or else it generates

     * an appropriate listen address. In either case, an address string

     * is returned from this method which can be used in starting target VMs

     * to identify this connector. The format of the address string

     * is connector, transport, and, possibly, platform dependent.

     * <p>

     * The argument map associates argument name strings to instances

     * of {@link Connector.Argument}. The default argument map for a

     * connector can be obtained through {@link Connector#defaultArguments}.

     * Argument map values can be changed, but map entries should not be

     * added or deleted.

     * <p>

     * This method does not return a {@link VirtualMachine}, and, normally,

     * returns before any target VM initiates

     * a connection. The connected target is obtained through

     * {@link #accept} (using the same argument map as is passed to this

     * method).

     * <p>

     * If {@code arguments} contains addressing information and

     * only one connection will be accepted, the {@link #accept accept} method

     * can be called immediately without calling this method.

     *

     * @return the address at which the connector is listening

     * for a connection.

     * @throws java.io.IOException when unable to start listening.

     * Specific exceptions are dependent on the Connector implementation

     * in use.

     * @throws IllegalConnectorArgumentsException when one of the

     * connector arguments is invalid.

     */

    String startListening(Map<String,? extends Connector.Argument> arguments)

        throws IOException, IllegalConnectorArgumentsException;

    /**

     * Cancels listening for connections. The given argument map should match

     * the argument map given for a previous {@link #startListening} invocation.

     *

     * @throws java.io.IOException when unable to stop listening.

     * Specific exceptions are dependent on the Connector implementation

     * in use.

     * @throws IllegalConnectorArgumentsException when one of the

     * connector arguments is invalid.

     */

    void stopListening(Map<String,? extends Connector.Argument> arguments)

        throws IOException, IllegalConnectorArgumentsException;

    /**

     * Waits for a target VM to attach to this connector.

     *

     * @throws TransportTimeoutException when the Connector encapsulates

     * a transport that supports a timeout when accepting, a

     * {@link Connector.Argument} representing a timeout has been set

     * in the argument map, and a timeout occurs whilst waiting for

     * the target VM to connect.

     * @throws java.io.IOException when unable to accept.

     * Specific exceptions are dependent on the Connector implementation

     * in use.

     * @throws IllegalConnectorArgumentsException when one of the

     * connector arguments is invalid.

     */

    VirtualMachine accept(Map<String,? extends Connector.Argument> arguments)

        throws IOException, IllegalConnectorArgumentsException;

}