在 Java 中使用 Runtime.exec() [英] using Runtime.exec() in Java

问题描述

在 Java 中你必须做什么才能让 Runtime.exec() 运行路径上的程序?我正在尝试运行已放入路径 (/usr/local/bin) 中的 gpsbabel.

What do you have to do in Java to get the Runtime.exec() to run a program that is on the path? I'm trying to run gpsbabel which I have put into the path (/usr/local/bin).

public class GpxLib {

    public static void main(String[] args) {
        try
        {
            Runtime r = Runtime.getRuntime();
            Process p = r.exec("gpsbabel -i garmin -f usb: -o gpx -F -");
            InputStream is = p.getInputStream();
            BufferedReader br = new BufferedReader(new InputStreamReader(is));
            while (true)
            {
                String s = br.readLine();
                if (s == null)
                    break;
                System.out.println(s);
            }
            br.readLine();
        } catch (IOException e) {
            e.printStackTrace(System.err);
        }
    }
}

推荐答案

它将继承 Java 进程的路径.因此，无论 Java 进程具有什么环境，生成的进程也将具有.以下是检查环境的方法:

It will inherit the path from the Java process. So whatever environment the Java process has, the spawned process will have as well. Here's how to check the environment:

Map<String, String> env = System.getenv();
for (String envName : env.keySet()) {
     System.out.format("%s=%s%n", envName, env.get(envName));
}

您是否设置了 PATH 并 将其导出?如果您不导出它，则它不可用于子进程.

Have you set the PATH and exported it ? If you don't export it, then it's not available to subprocesses.

此外，您必须同时使用 stdout 和 stderr，以防止阻塞.否则在某些情况下东西会起作用，那么您生成的进程将输出不同数量的数据，一切都会停止.

Additionally, you must consume stdout and stderr concurrently, to prevent blocking. Otherwise stuff will work in some circumstances, then your spawned process will output a different quantity of data and everything will grind to a halt.

有关详细信息，请参阅此答案.

See this answer for more details.

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