code: // Licensed to the Software Freedom Conservancy (SFC) under one
  // or more contributor license agreements.  See the NOTICE file
  // distributed with this work for additional information
  // regarding copyright ownership.  The SFC 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
  //
  //   http://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.openqa.selenium.os;
  
  import static org.openqa.selenium.Platform.MAC;
  import static org.openqa.selenium.Platform.WINDOWS;
  
  import java.io.File;
  import java.io.OutputStream;
  import java.util.Map;
  import java.util.concurrent.TimeUnit;
  import org.openqa.selenium.Platform;
  import org.openqa.selenium.WebDriverException;
  
  public class CommandLine {
  
    private final OsProcess process;
  
    public CommandLine(String executable, String... args) {
      process = new OsProcess(executable, args);
    }
  
    /**
     * Adds the specified environment variables.
     *
     * @param environment the variables to add
     * @throws IllegalArgumentException if any value given is null (unsupported)
     */
    public void setEnvironmentVariables(Map<String, String> environment) {
      for (Map.Entry<String, String> entry : environment.entrySet()) {
        setEnvironmentVariable(entry.getKey(), entry.getValue());
      }
    }
  
    /**
     * Adds the specified environment variable.
     *
     * @param name the name of the environment variable
     * @param value the value of the environment variable
     * @throws IllegalArgumentException if the value given is null (unsupported)
     */
    public void setEnvironmentVariable(String name, String value) {
      process.setEnvironmentVariable(name, value);
    }
  
    public void setDynamicLibraryPath(String newLibraryPath) {
      // because on Windows, it is null according to SingleBrowserLocator.computeLibraryPath()
      if (newLibraryPath != null) {
        setEnvironmentVariable(getLibraryPathPropertyName(), newLibraryPath);
      }
    }
  
    public void updateDynamicLibraryPath(String extraPath) {
      if (extraPath != null) {
        String existing = System.getenv(getLibraryPathPropertyName());
        String ldPath = existing != null ? existing + File.pathSeparator + extraPath : extraPath;
        setEnvironmentVariable(getLibraryPathPropertyName(), ldPath);
      }
    }
  
    /**
     * @return The platform specific env property name which contains the library path.
     */
    public static String getLibraryPathPropertyName() {
      Platform current = Platform.getCurrent();
  
      if (current.is(WINDOWS)) {
        return "PATH";
  
      } else if (current.is(MAC)) {
        return "DYLD_LIBRARY_PATH";
  
      } else {
        return "LD_LIBRARY_PATH";
      }
    }
  
    public void executeAsync() {
      process.executeAsync();
    }
  
    public void execute() {
      executeAsync();
      waitFor();
    }
  
    public boolean waitForProcessStarted(long duration, TimeUnit unit) {
      return process.waitForProcessStarted(duration, unit);
    }
  
    public void waitFor() {
      try {
        process.waitFor();
      } catch (InterruptedException e) {
        Thread.currentThread().interrupt();
        throw new WebDriverException(e);
      }
    }
  
    public void waitFor(long timeout) {
      try {
        process.waitFor(timeout);
      } catch (InterruptedException e) {
        Thread.currentThread().interrupt();
        throw new WebDriverException(e);
      }
    }
  
    public boolean isSuccessful() {
      return 0 == getExitCode();
    }
  
    public int getExitCode() {
      return process.getExitCode();
    }
  
    public String getStdOut() {
      return process.getStdOut();
    }
  
    /**
     * Destroy the current command.
     *
     * @return The exit code of the command.
     */
    public int destroy() {
      return process.destroy();
    }
  
    /**
     * Check whether the current command is still executing.
     *
     * @return true if the current command is still executing, false otherwise
     */
    public boolean isRunning() {
      return process.isRunning();
    }
  
    public void setInput(String allInput) {
      process.setInput(allInput);
    }
  
    public void setWorkingDirectory(String workingDirectory) {
      process.setWorkingDirectory(new File(workingDirectory));
    }
  
    @Override
    public String toString() {
      return process.toString();
    }
  
    public void copyOutputTo(OutputStream out) {
      process.copyOutputTo(out);
    }
  
    public void checkForError() {
      process.checkForError();
    }
  }
  