的Java的ProcessBuilder如何从命令二进制输出(Java ProcessBuilder

我试图使用执行使用的ProcessBuilder的命令。该命令应该写在标准输出二进制数据。我怎样才能得到我的byte []这个数据？

这是一个工作示例，它返回true输出1和false输出0 ，（在所有其它情况下抛出异常）。我还添加了设定的工作路径和环境变量，它不需要你的具体的例子，所以你可以将其删除。

您可以复制该代码粘贴为一类，编译它JAR并运行。
它在WSL的Ubuntu 16.04进行验证。

设置workdirectory通过设置验证binaryCommand[0]="touch"; 和binaryCommand[1]="1"; ，重新编译和运行.jar文件。

 import java.io.BufferedReader; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.io.PrintWriter; import java.util.Arrays; import java.util.Map; import java.util.StringJoiner; public class GenerateOutput { /** * This code can execute a command and return the binary value of it's output if it * is actually binary. * * compile this project into a .jar and run it with for example: * java -jar readOutputOfCommand.jar * * @param args * @throws Exception */ public static void main(String[] args) throws Exception { boolean answerYes = false; // no yes answer to any command prompts is needed. // to execute a command with spaces in it in terminal, put them in an array of Strings. String[] binaryCommand = new String[2]; // write a command that gives a binary output: binaryCommand[0] = "echo"; binaryCommand[1] = "1"; // pass the commands to a method that executes them System.out.println("The output of the echo command = "+executeCommands(binaryCommand,answerYes)); } /** * This executes the commands in terminal. * Additionally it sets an environment variable (not necessary for your particular solution) * Additionally it sets a working path (not necessary for your particular solution) * @param commandData * @param ansYes * @throws Exception */ public static boolean executeCommands(String[] commands,Boolean ansYes) throws Exception { String capturedCommandOutput = null; System.out.println("Incoming commandData = "+Arrays.deepToString(commands)); File workingDirectory = new File("/mnt/c/testfolder b/"); // create a ProcessBuilder to execute the commands in ProcessBuilder processBuilder = new ProcessBuilder(commands); // this is not necessary but can be used to set an environment variable for the command processBuilder = setEnvironmentVariable(processBuilder); // this is not necessary but can be used to set the working directory for the command processBuilder.directory(workingDirectory); // execute the actual commands try { Process process = processBuilder.start(); // capture the output stream of the command BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream())); StringJoiner sj = new StringJoiner(System.getProperty("line.separator")); reader.lines().iterator().forEachRemaining(sj::add); capturedCommandOutput = sj.toString(); System.out.println("The output of this command ="+ capturedCommandOutput); // here you connect the output of your command to any new input, eg if you get prompted for `yes` new Thread(new SyncPipe(process.getErrorStream(), System.err)).start(); new Thread(new SyncPipe(process.getInputStream(), System.out)).start(); PrintWriter stdin = new PrintWriter(process.getOutputStream()); //This is not necessary but can be used to answer yes to being prompted if (ansYes) { System.out.println("WITH YES!"); stdin.println("yes"); } // write any other commands you want here stdin.close(); // this lets you know whether the command execution led to an error(!=0), or not (=0). int returnCode = process.waitFor(); System.out.println("Return code = " + returnCode); } catch (IOException e1) { e1.printStackTrace(); } return retrieveBooleanOutput(capturedCommandOutput); } private static boolean retrieveBooleanOutput(String commandOutput) throws Exception { if (commandOutput != null && commandOutput.length() == 1) { if (commandOutput.contains("0")) { return false; } else if (commandOutput.contains("1")) { return true; } } throw new Exception("The output is not binary."); } /** * source: https://stackoverflow.com/questions/7369664/using-export-in-java * @param processBuilder * @param varName * @param varContent * @return */ private static ProcessBuilder setEnvironmentVariable(ProcessBuilder processBuilder){ String varName = "variableName"; String varContent = "/mnt/c/testfolder a/"; Map<String, String> env = processBuilder.environment(); System.out.println("Setting environment variable "+varName+"="+varContent); env.put(varName, varContent); processBuilder.environment().put(varName, varContent); return processBuilder; } } class SyncPipe implements Runnable { /** * This class pipes the output of your command to any new input you generated * with stdin. For example, suppose you run cp /mnt/c/a.txt /mnt/b/ * but for some reason you are prompted: "do you really want to copy there yes/no? * then you can answer yes since your input is piped to the output of your * original command. (At least that is my practical interpretation might be wrong.) * @param istrm * @param ostrm */ public SyncPipe(InputStream istrm, OutputStream ostrm) { istrm_ = istrm; ostrm_ = ostrm; } public void run() { try { final byte[] buffer = new byte[1024]; for (int length = 0; (length = istrm_.read(buffer)) != -1; ) { ostrm_.write(buffer, 0, length); } } catch (Exception e) { e.printStackTrace(); } } private final OutputStream ostrm_; private final InputStream istrm_; }