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 * Copyright (c) 2016, 2017, 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 jdk.jshell.execution;

import java.io.IOException;

import java.util.HashMap;

import java.util.Locale;

import java.util.Map;

import jdk.jshell.spi.ExecutionControl;

import jdk.jshell.spi.ExecutionControlProvider;

import jdk.jshell.spi.ExecutionEnv;

/**

 * A provider of remote JDI-controlled execution engines.

 *

 * @author Robert Field

 * @since 9

 */

public class JdiExecutionControlProvider implements ExecutionControlProvider {

    /**

     * The remote agent to launch.

     */

    public static final String PARAM_REMOTE_AGENT = "remoteAgent";

    /**

     * Milliseconds before connect timeout.

     */

    public static final String PARAM_TIMEOUT = "timeout";

    /**

     * The local hostname to connect to.

     */

    public static final String PARAM_HOST_NAME = "hostname";

    /**

     * Should JDI-controlled launching be used?

     */

    public static final String PARAM_LAUNCH = "launch";

    /**

     * Default time-out expressed in milliseconds.

     */

    private static final int DEFAULT_TIMEOUT = 5000;

    /**

     * Create an instance.  An instance can be used to

     * {@linkplain  #generate generate} an {@link ExecutionControl} instance

     * that uses the Java Debug Interface as part of the control of a remote

     * process.

     */

    public JdiExecutionControlProvider() {

    }

    /**

     * The unique name of this {@code ExecutionControlProvider}.

     *

     * @return "jdi"

     */

    @Override

    public String name() {

        return "jdi";

    }

    /**

     * Create and return the default parameter map for this

     * {@code ExecutionControlProvider}. The map can optionally be modified;

     * Modified or unmodified it can be passed to

     * {@link #generate(jdk.jshell.spi.ExecutionEnv, java.util.Map) }.

     * <table>

     * <caption>Parameters</caption>

     *   <tr>

     *     <th>Parameter</th>

     *     <th>Description</th>

     *     <th>Constant Field</th>

     *   </tr>

     *   <tr>

     *     <td>remoteAgent</td>

     *     <td>the remote agent to launch</td>

     *     <td>{@link #PARAM_REMOTE_AGENT}</td>

     *   </tr>

     *   <tr>

     *     <td>timeout</td>

     *     <td>milliseconds before connect timeout</td>

     *     <td>{@link #PARAM_TIMEOUT}</td>

     *   </tr>

     *   <tr>

     *     <td>launch</td>

     *     <td>"true" for JDI controlled launch</td>

     *     <td>{@link #PARAM_LAUNCH}</td>

     *   </tr>

     *   <tr>

     *     <td>hostname</td>

     *     <td>connect to the named of the local host ("" for discovered)</td>

     *     <td>{@link #PARAM_HOST_NAME}</td>

     *   </tr>

     * </table>

     *

     * @return the default parameter map

     */

    @Override

    public Map<String, String> defaultParameters() {

        Map<String, String> dp = new HashMap<>();

        dp.put(PARAM_REMOTE_AGENT, RemoteExecutionControl.class.getName());

        dp.put(PARAM_TIMEOUT, "" + DEFAULT_TIMEOUT);

        dp.put(PARAM_HOST_NAME, "");

        dp.put(PARAM_LAUNCH, "false");

        return dp;

    }

    @Override

    public ExecutionControl generate(ExecutionEnv env, Map<String, String> parameters)

            throws IOException {

        Map<String, String> dp  = defaultParameters();

        if (parameters == null) {

            parameters = dp;

        }

        String remoteAgent = parameters.getOrDefault(PARAM_REMOTE_AGENT, dp.get(PARAM_REMOTE_AGENT));

        int timeout = Integer.parseUnsignedInt(

                parameters.getOrDefault(PARAM_TIMEOUT, dp.get(PARAM_TIMEOUT)));

        String host = parameters.getOrDefault(PARAM_HOST_NAME, dp.get(PARAM_HOST_NAME));

        String sIsLaunch = parameters.getOrDefault(PARAM_LAUNCH, dp.get(PARAM_LAUNCH)).toLowerCase(Locale.ROOT);

        boolean isLaunch = sIsLaunch.length() > 0

                && ("true".startsWith(sIsLaunch) || "yes".startsWith(sIsLaunch));

        return JdiDefaultExecutionControl.create(env, remoteAgent, isLaunch, host, timeout);

    }

}