Java 通过ProcessBuilder或Runtime.exec()调用(cmd/sh)系统命令方法代码

1、操作系统判断

boolean isWindows = System.getProperty("os.name")
  .toLowerCase().startsWith("windows");

2、读取调用命令的输出

输出(Output)必须被读取，否则我们的进程将挂起，不能成功返回。

通过StreamGobbler类来读取InputStream:

private static >StreamGobbler implements Runnable {
    private InputStream inputStream;
    private Consumer<String> consumer;
    public StreamGobbler(InputStream inputStream, Consumer<String> consumer) {
        this.inputStream = inputStream;
        this.consumer = consumer;
    }
    @Override
    public void run() {
        new BufferedReader(new InputStreamReader(inputStream)).lines()
          .forEach(consumer);
    }
}

3、使用Runtime.exec()调用cmd命令和shell命令并将结果输出到控制台

String homeDirectory = System.getProperty("user.home");
Process process;
if (isWindows) {
    process = Runtime.getRuntime()
      .exec(String.format("cmd.exe /c dir %s", homeDirectory));
} else {
    process = Runtime.getRuntime()
      .exec(String.format("sh -c ls %s", homeDirectory));
}
StreamGobbler streamGobbler = 
  new StreamGobbler(process.getInputStream(), System.out::println);
Executors.newSingleThreadExecutor().submit(streamGobbler);
int exitCode = process.waitFor();
assert exitCode == 0;

4、使用ProcessBuilder调用cmd命令和shell命令并将结果输出到控制台

对于有些复杂的处理，可以使用ProcessBuilder，使用它可以：

• 使用builder.directory()更改我们的shell命令正在运行的工作目录
• 使用builder.environment()将自定义键值映射设置为环境变量
• 将输入和输出流重定向到自定义替换
• 使用builder.inheritIO()将它们都继承到当前JVM进程的流

ProcessBuilder builder = new ProcessBuilder();
if (isWindows) {
    builder.command("cmd.exe", "/c", "dir");
} else {
    builder.command("sh", "-c", "ls");
}
builder.directory(new File(System.getProperty("user.home")));
Process process = builder.start();
StreamGobbler streamGobbler = 
  new StreamGobbler(process.getInputStream(), System.out::println);
Executors.newSingleThreadExecutor().submit(streamGobbler);
int exitCode = process.waitFor();
assert exitCode == 0;

参考文档：https://www.baeldung.com/run-shell-command-in-java