java - Android - 无法在模拟器中执行简单的 cd

Question

• 我有一个已root的模拟器(尽管我不确定它是相关)

• 我正在尝试为我的论文构建一个根应用程序，当按钮按下时按下后，它会尝试查找数据库文件。

• 我已经尝试从以下位置执行 shell 命令在应用程序中(java代码)，但我所能做的就是ls。

• 当我尝试 cd 到另一个文件夹时，它不起作用。 cd 之后我执行 pwd 或 ls 仍然给出 / 的结果。

• 下面是我的代码的相关部分

  Button btn_read = (Button) findViewById(R.id.button);
      btn_read.setOnClickListener(new View.OnClickListener() {
          @Override
          public void onClick(View v) {
              /*String s;
  
              try {
                  Process p = Runtime.getRuntime().exec("ls -al");
                  p = Runtime.getRuntime().exec("adb shell");
                  p = Runtime.getRuntime().exec("cd data/data");
  
                  BufferedReader stdInput = new BufferedReader(new
                          InputStreamReader(p.getInputStream()));
  
                  BufferedReader stdError = new BufferedReader(new
                          InputStreamReader(p.getErrorStream()));
  
                  // read the output from the command
                  Log.d("ReadDB", "Here is the standard output of the command:\n");
                  while ((s = stdInput.readLine()) != null) {
                      Log.d("ReadDB", s);
                  }
  
                  // read any errors from the attempted command
                  Log.d("ReadDB", "Here is the standard error of the command (if any):\n");
                  while ((s = stdError.readLine()) != null) {
                      Log.d("ReadDB", s);
                  }
  
                  System.exit(0);
              }
              catch (IOException e) {
                  Log.d("ReadDB", "Exception happened - here's what I know: ");
                  e.printStackTrace();
                  System.exit(-1);
              }*/
  
              executeCommand(new String[] {
                  "sh", "-c", "ls -l"
              });
              /*executeCommand(new String[] {
                  "sh", "-c", "cd /mnt"
              });*/
              executeCommand(new String[] {
                  "sh", "-c", "ls -l data/data"
              });
              executeCommand(new String[] {
                  "sh", "-c", "pwd"
              });
          }
      });
  }
  
  private static void executeCommand(String[] commands) {
      Process p;
      try {
          p = Runtime.getRuntime().exec(commands);
          p.waitFor();
          BufferedReader reader =
                  new BufferedReader(new InputStreamReader(p.getInputStream()));
  
          String line = "";
          while ((line = reader.readLine())!= null) {
              Log.d("ReadDB", line + "\n");
          }
          Log.d("ReadDB", "--------------------------------------------------------------------------------------");
  
      } catch (Exception e) {
          Log.d("ReadDB", "Exception occured");
          e.printStackTrace();
      }
  }
  

有人可以帮忙吗？

Answer 1

这些命令将在单独的 subshells 中运行，所以这是不可能的。什么应该有效:

executeCommand(new String[] {
    "sh", "-c", "cd /mnt && some other command"
});