Java基于Runtime调用外部程序出现阻塞的解决方法

InputStream stderr = process.getInputStream();InputStreamReader isr = new InputStreamReader(stderr, "GBK");BufferedReader br = new BufferedReader(isr);String line = null;while ((line = br.readLine()) != null)  System.out.println(line);int exitValue = process.waitFor();

@SuppressWarnings("static-access")public static int doWaitFor(Process process) {  InputStream in = null;  InputStream err = null;  int exitValue = -1; // returned to caller when p is finished  try {    in = process.getInputStream();    err = process.getErrorStream();    boolean finished = false; // Set to true when p is finished    while (!finished) {      try {        while (in.available() > 0) {          // Print the output of our system call          Character c = new Character((char) in.read());          System.out.print(c);        }        while (err.available() > 0) {          // Print the output of our system call          Character c = new Character((char) err.read());          System.out.print(c);        }        // Ask the process for its exitValue. If the process        // is not finished, an IllegalThreadStateException        // is thrown. If it is finished, we fall through and        // the variable finished is set to true.        exitValue = process.exitValue();        finished = true;      } catch (IllegalThreadStateException e) {        // Process is not finished yet;        // Sleep a little to save on CPU cycles        Thread.currentThread().sleep(500);      }    }  } catch (Exception e) {    e.printStackTrace();  } finally {    try {      if (in != null) {        in.close();      }    } catch (IOException e) {      e.printStackTrace();    }    if (err != null) {      try {        err.close();      } catch (IOException e) {        e.printStackTrace();      }    }  }  return exitValue;}