/*

 * Copyright (c) 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.

 *

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package jdk.jshell.spi;

import java.io.InputStream;

import java.io.PrintStream;

import java.util.List;

/**

 * Functionality made available to a pluggable JShell execution engine.  It is

 * provided to the execution engine by the core JShell implementation.

 * <p>

 * This interface is designed to provide the access to core JShell functionality

 * needed to implement ExecutionControl.

 *

 * @since 9

 * @see ExecutionControl

 */

public interface ExecutionEnv {

    /**

     * Returns the user's input stream.

     *

     * @return the user's input stream

     */

    InputStream userIn();

    /**

     * Returns the user's output stream.

     *

     * @return the user's output stream

     */

    PrintStream userOut();

    /**

     * Returns the user's error stream.

     *

     * @return the user's error stream

     */

    PrintStream userErr();

    /**

     * Returns the additional VM options to be used when launching the remote

     * JVM. This is advice to the execution engine.

     * <p>

     * Note: an execution engine need not launch a remote JVM.

     *

     * @return the additional options with which to launch the remote JVM

     */

    List<String> extraRemoteVMOptions();

    /**

     * Reports that the execution engine has shutdown.

     */

    void closeDown();

}