public class SerialPort {  /*Do not remove or rename the field mFd: it is used by native method close();*/  public SerialPort(File device, int baudrate, int flags) throws SecurityException, IOException, InvalidParameterException{ //如果串口权限不够，改变权限   /* Check access permission */   if (!device.canRead() || !device.canWrite()) {    try {     /* Missing read/write permission, trying to chmod the file */     Process su;     su = Runtime.getRuntime().exec("/system/bin/su");     String cmd = "chmod 666 " + device.getAbsolutePath() + "\n"       + "exit\n";     su.getOutputStream().write(cmd.getBytes());     if ((su.waitFor() != 0) || !device.canRead()       || !device.canWrite()) {      throw new SecurityException();     }    } catch (Exception e) {     e.printStackTrace();     throw new SecurityException();    }   }   mFd = open(device.getAbsolutePath(), baudrate, flags);//打开串口   if (mFd == null) {    Log.e(TAG, "native open returns null");    throw new IOException();   }   mFileInputStream = new FileInputStream(mFd);//串口输入流   mFileOutputStream = new FileOutputStream(mFd);//串口输出流  }  // Getters and setters  public InputStream getInputStream() {   return mFileInputStream;  }  public OutputStream getOutputStream() {   return mFileOutputStream;  }  // JNI  private native static FileDescriptor open(String path, int baudrate, int flags);//c文件中的串口open()函数  public native void close();//c文件中的串口close()函数  static {   System.loadLibrary("serial_port");//加载串口库  } } }

public abstract class ServerData {  protected SerialPort mSerialPort;  protected OutputStream mOutputStream;  private InputStream mInputStream;  private ReadThread mReadThread;  private class ReadThread extends Thread {   @Override   //在线程中读取数据并处理数据   public void run() {    super.run();    byte[] buffer = new byte[128];    int size;    while(true) {     try {      if (mInputStream == null) return;      size = mInputStream.read(buffer);//读取数据      if (size > 0) {       onDataReceived(buffer, size);//处理数据      }     } catch (IOException e) {      e.printStackTrace();      return;     }    }   }  } 4.实例化串口类，输出流和输入流，实例化读取线程并开始执行该线程 [code]  public ServerData(String path, int baudrate){   try {    mSerialPort = new SerialPort(new File(path), baudrate, 0);    mOutputStream = mSerialPort.getOutputStream();    mInputStream = mSerialPort.getInputStream();    /* Create a receiving thread */    mReadThread = new ReadThread();    mReadThread.start();   } catch (SecurityException e) {   } catch (IOException e) {   } catch (InvalidParameterException e) {   }  }  protected abstract void onDataReceived(final byte[] buffer, final int size); }

package View; //导入R类，所在包不同，不能直接饮用，需要导入才可以使用 import android_serialport_api.sample.R; /* EtcView类，Etc界面管理 */ public class SerialView {  private Activity context = null;  private Serial mEtcServer = null;  /* Etc界面构造函数 */  public SerialView(Activity context) {   this.context = context;  }  public void EtcInitView() {   //这样才可以找到android_serialport_api.sample包下的id   TextView mytext=(TextView)context.findViewById(R.id.mytext);   mEtcServer = new Serial("/dev/s3c2410_serial3", 9600);  }  public void EtcRefresh() {   //返回串口线程读取的数据   byte[] buffer = mEtcServer.getdata();   String recString=new String(buffer);//将byte[]的数组转换成字符串string   mytext.setText(recString);//设置字符文本   buffer = null;  } }