CommandLauncher.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package org.apache.commons.exec.launcher;

import java.io.File;
import java.io.IOException;
import java.nio.file.Path;
import java.util.Map;

import org.apache.commons.exec.CommandLine;

/**
 * Abstracts platform-dependent implementations.
 */
public interface CommandLauncher {

    /**
     * Executes the given command in a new process.
     *
     * @param commandLine The command to execute.
     * @param env         The environment for the new process. If null, the environment of the current process is used.
     * @return the newly created process.
     * @throws IOException if attempting to run a command in a specific directory.
     */
    Process exec(final CommandLine commandLine, final Map<String, String> env) throws IOException;

    /**
     * Executes the given command in a new process, in the given working directory.
     *
     * @param commandLine      The command to execute.
     * @param env              The environment for the new process. If null, the environment of the current process is used.
     * @param workingDirectory The directory to start the command in. If null, the current directory is used.
     * @return the newly created process.
     * @throws IOException if trying to change directory.
     */
    Process exec(final CommandLine commandLine, final Map<String, String> env, final File workingDirectory) throws IOException;

    /**
     * Executes the given command in a new process, in the given working directory.
     *
     * @param commandLine      The command to execute.
     * @param env              The environment for the new process. If null, the environment of the current process is used.
     * @param workingDirectory The directory to start the command in. If null, the current directory is used.
     * @return the newly created process.
     * @throws IOException if trying to change directory.
     * @since 1.5.0
     */
    default Process exec(final CommandLine commandLine, final Map<String, String> env, final Path workingDirectory) throws IOException {
        return exec(commandLine, env, workingDirectory != null ? workingDirectory.toFile() : null);
    }

    /**
     * Tests whether {@code exitValue} signals a failure on the current system (OS specific).
     * <p>
     * <strong>Note</strong> that this method relies on the conventions of the OS, it will return false results if the application you are running doesn't
     * follow these conventions. One notable exception is the Java VM provided by HP for OpenVMS - it will return 0 if successful (like on any other platform),
     * but this signals a failure on OpenVMS. So if you execute a new Java VM on OpenVMS, you cannot trust this method.
     * </p>
     *
     * @param exitValue the exit value (return code) to be checked.
     * @return {@code true} if {@code exitValue} signals a failure.
     */
    boolean isFailure(final int exitValue);
}