從Java運行python腳本時找不到mvn命令

Question

目前，我可以使用Process在Java中啟動python程序。

問題是，盡管我已經正確安裝了maven並且能夠從終端運行python程序，但是Process無法識別python程序中的mvn命令。

這就是我使用Process ：

public static String runCommand(String directory, List<String> command) {

    ProcessBuilder processBuilder = new ProcessBuilder(command).directory(new File(directory));

    processBuilder.redirectErrorStream(true);

    Process process;
    String output = null;
    try {
        process = processBuilder.start();


        //Pause the current thread until the process is done
        process.waitFor();

        //When the process does not exit properly
        if (process.exitValue() != 0) {

            //Error
            System.out.println("command exited in error: " + process.exitValue());

            //Handle the error
            return readOutput(process);
        }else {

            output = readOutput(process);
            System.out.println(output);
        }

    } catch (InterruptedException e) {
        System.out.println("Something wrong with command: " +e.getMessage());

    } catch (IOException e) {
        System.out.println("Something wrong with command: " +e.getMessage());
    }

    return output;
}`

驅動程序代碼：

    List<String> csi = new ArrayList<>();
    CSI_PATH = getClass().getResource("/python/csi").getPath();
    System.out.println("CSI path:" + CSI_PATH);


    //Construct the argument
    csi.add(CSI_PATH);
    //argument for the csi program
    csi.add(pre_hash);
    csi.add(post_hash);

    String csi_output = Command.runCommand(project_directory, csi);

    System.out.println(csi_output);

我可以用Java做些什么讓Process識別python程序中的mvn嗎？

csi程序的相關部分：

os.sys_call("git checkout " + commit_hash)
os.sys_call("mvn clean")
bin_path = mvn.path_from_mvn_call("outputDirectory")
src_rel_path = mvn.path_from_mvn_call("sourceDirectory")


def path_from_mvn_call(env):
    if env not in ["sourceDirectory", "scriptSourceDirectory", "testSourceDirectory", 
               "outputDirectory", "testOutputDirectory", "directory"]:
        raise ValueError("incorrect env var: " + env)
    mvn_cmd = "mvn help:evaluate -Dexpression=project.build." + env + " | grep ^/"
    return subprocess.check_output(mvn_cmd, shell=True).strip()

def sys_call(cmd, ignore_bad_exit=False):
    ret = subprocess.call(cmd, shell=True)
    if ret != 0:
        print "\n-- << non-zero exit status code >> --"
        if ignore_bad_exit:
            print "Exit from command: \n\t" + cmd
            print "But we can safely ignore such non-zero exit status code this time.\n"
        else:
            print "Error in command: \n\t" + cmd + "\n"
            raise SystemExit("system exit: " + str(ret))

提前謝謝！

編輯：我已經嘗試過這篇文章如何啟動具有標准bash shell環境的Java進程？

所以我將代碼更改為

      //Construct the argument
      csi.add("/bin/bash");
      csi.add("-l");
      csi.add("-c");
      csi.add("\"" + csi_path + " " + pre_hash+ " " + post_hash + "\"");
      String csi_output = Command.runCommand(project_directory, csi);

但是即使如此，該命令也會退出127，這意味着Value 127 is returned by your shell /bin/bash when any given command within your bash script or on bash command line is not found in any of the paths defined by PATH system environment variable.

如果我在Java中運行/bin/bash -l -c "mvn --version" ，它仍然會退出127。

Answer 1

Python從您的終端繼承了所有環境。 從Python產生的子流程應該繼承父流程的所有環境。 所以我不確定為什么會發生錯誤mvn。 您可以嘗試python subprocess：

import subprocess
args = ['mvn', '-version']
process = subprocess.Popen(args, stdout=subprocess.PIPE)

要么

import subprocess
args = ['mvn', '-version']
process = subprocess.Popen(args,shell=True)