我正在开发一个小的java应用程序,需要启动python脚本并与之交互。python脚本将在后台运行并等待命令。在每个命令之后,我期望一个响应,它将被转发回java应用程序。
我的问题是,如何在不重新运行python脚本钩子的情况下运行我的命令?
public void startProcess()
{
try {
p = Runtime.getRuntime().exec("python " + scriptPath);
} catch (IOException e) {
e.printStackTrace();
}
}
public String executeCommand(String cmd)
{
String consoleResponse = "";
try {
// how do I perform something similar to p.exec(cmd)
BufferedReader stdInput = new BufferedReader(new
InputStreamReader(p.getInputStream()));
BufferedReader stdError = new BufferedReader(new
InputStreamReader(p.getErrorStream()));
// read the output from the command
System.out.println("Here is the standard output of the command:\n");
while ((consoleResponse += stdInput.readLine()) != null) {
}
// read any errors from the attempted command
System.out.println("Here is the standard error of the command (if any):\n");
while ((consoleResponse = stdError.readLine()) != null) {
}
} catch (IOException e) {
e.printStackTrace();
}
return consoleResponse;
}
编辑: python脚本是针对BACpypes的。这个脚本做了3件事。SendFile:获取通过be连接的所有设备的列表。ReadHexFile:读取要发送到网络上所有设备的文本文件。WhoIs:将文件发送到所有设备。
我没有使用python的经验,我觉得在一个脚本中保存所有这些数据会更简单。
我认为一种选择是将每个命令分解成其自己的脚本,并将数据传递给java应用程序。
发布于 2018-07-26 22:19:28
如何在不重新运行python脚本钩子的情况下运行我的命令?
您需要让单个Python脚本不断侦听新的输入或请求(来回通信),但我认为这将是一种轻微的痛苦,而且还会使您的python脚本不像标准的input -> process -> output
流那样清晰。
避免运行多个Python脚本的原因是什么?
要将输入写入脚本stdin,请执行以下操作:
public static void main(String[] args) throws IOException, InterruptedException {
ProcessBuilder pb = new ProcessBuilder("python", "path\\to\\script.py");
Process pr = pb.start();
try (BufferedWriter writerToProc = new BufferedWriter(
new OutputStreamWriter(pr.getOutputStream()));
BufferedReader readerOfProc = new BufferedReader(
new InputStreamReader(pr.getInputStream()));
BufferedReader errorsOfProc = new BufferedReader(
new InputStreamReader(pr.getErrorStream()))) {
writerToProc.write("WhoIs\n");
writerToProc.write("ReadHexFile\n"); // is this the syntax?
writerToProc.write("SendFile 'path\to\file.txt'\n");
writerToProc.flush();
StringBuilder procOutput = new StringBuilder();
boolean gaveUp = false;
long waitTime = 10 * 1_000; // 10 seconds
long lastRead = System.currentTimeMillis();
for(;;) {
final long currTime = System.currentTimeMillis();
final int available = readerOfProc.available();
if(available > 0){
// TODO read the available bytes without blocking
byte[] bytes = new byte[available];
readerOfProc.read(bytes);
procOutput.append(new String(bytes));
// maybe check this input for an EOF code
// your python task should write EOF when it has finished
lastRead = currTime;
} else if((currTime - lastRead) > waitTime){
gaveUp = true;
break;
}
}
// readerOfProc.lines().forEach((l) -> System.out.println(l));
// errorsOfProc.lines().forEach((l) -> System.out.println(l));
}
}
https://stackoverflow.com/questions/51540597
复制相似问题