【Android】 ProcessBuild Process su 命令

ProcessBuilder pb = new ProcessBuilder("su");
//othre pb setting,such as dir, env

Process p = pb.start();

OutputStream out;
out = p.getOutputStream();
out.write(cmd.getBytes());
...

//失败1
pb = new ProcessBuilder("su",cmd);
p = pb.start();
...

//失败2
List<String> list = new ArrayList();
list.add("su");
list.add(cmd);
pb = new ProcessBuilder(list);
p = pb.start();
...