Question

我可以在Linux上执行由processBuilder包装的常用命令。但是我目前正在尝试像以下示例中那样运行Minecraft服务器，并在命令前设置了一些变量，但它失败并出现异常。

final ProcessBuilder processBuilder = new ProcessBuilder("LD_LIBRARY_PATH=. ./bedrock_server");
processBuilder.directory(MC_PAL_LOCATION_DIR.toFile());
process = processBuilder.start();

例外：

java.io.IOException: Cannot run program "LD_LIBRARY_PATH=. ./bedrock_server" (in directory "/home/user/Desktop/minecraft_bedrock_server_t"): error=2, No such file or directory
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
    at controller.Server.startMinecraftServer(Server.java:91)
    at controller.Server.start(Server.java:58)
    at Bootstrapper.bootServer(Bootstrapper.java:67)
    at Bootstrapper.main(Bootstrapper.java:30)
Caused by: java.io.IOException: error=2, No such file or directory
    at java.lang.UNIXProcess.forkAndExec(Native Method)
    at java.lang.UNIXProcess.<init>(UNIXProcess.java:247)
    at java.lang.ProcessImpl.start(ProcessImpl.java:134)
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
    ... 4 more
Exception in thread "Thread-0" java.lang.NullPointerException
    at controller.ConsoleInput.run(ConsoleInput.java:16)
    at java.lang.Thread.run(Thread.java:748)

是否有可能将processBuilder用于此类命令？如果我直接将其粘贴到终端，则该命令有效。

链接到服务器：https://minecraft.net/en-us/download/server/bedrock/

命令：LD_LIBRARY_PATH=. ./bedrock_server

Answer 1

没有bash，您将无法使用bash shell命令。但是您可以自己以编程方式操纵环境。喜欢，

final ProcessBuilder processBuilder = new ProcessBuilder("./bedrock_server");
processBuilder.environment().put("LD_LIBRARY_PATH", ".");
processBuilder.directory(MC_PAL_LOCATION_DIR.toFile());
process = processBuilder.start();

Answer 2

正如@ElliottFrisch指出的那样，没有bash就不能使用shell命令，因此，您要向环境映射添加LD_LIBRARY_PATH或执行bash：

    final ProcessBuilder processBuilder = new ProcessBuilder("bash", "-c",  "LD_LIBRARY_PATH=. ./bedrock_server");
    processBuilder.directory(MC_PAL_LOCATION_DIR.toFile());
    process = processBuilder.start();

ProcessBuilder在包含本地环境变量的命令上失败

2 个答案: