求助！这些代码如何在NetBeans IDE 3.5.1下编译通过？(50分)

是关于串口通讯的，它有三个类，和一个例子。
http://www.gjwtech.com/scomm/sc2javacommprog.htm
这是程序来源。
我还要怎么改动才能成功编译？
我也是刚学java，类的调用什么的还不是很清楚。
该死的老板一定要我用java写！！
package serial;
/**
*
* This bean provides some basic functions to implement full dulplex
* information exchange through the srial port.
*
*/
import java.io.*;
import java.util.*;
import javax.comm.*;
import java.awt.Graphics;
import java.awt.*;
class SerialBean
{
static String PortName;
CommPortIdentifier portId;
SerialPort serialPort;
static OutputStream out;
static InputStream in;
SerialBuffer SB;
ReadSerial RT;
/**
*
* Constructor
*
* @param PortID the ID of the serial to be used. 1 for COM1,
* 2 for COM2, etc.
*
*/
public SerialBean(int PortID)
{
PortName = "COM" + PortID;
}
/**
*
* This function initialize the serial port for communication. It startss a
* thread which consistently monitors the serial port. Any signal capturred
* from the serial port is stored into a buffer area.
*
*/
public int Initialize()
{
int InitSuccess = 1;
int InitFail = -1;
try
{
portId = CommPortIdentifier.getPortIdentifier(PortName);
try
{
serialPort = (SerialPort)
portId.open("Serial_Communication", 2000);
} catch (PortInUseException e)
{
return InitFail;
}
//Use InputStream in to read from the serial port, and OutputStream
//out to write to the serial port.
try
{
in = serialPort.getInputStream();
out = serialPort.getOutputStream();
} catch (IOException e)
{
return InitFail;
}
//Initialize the communication parameters to 9600, 8, 1, none.
try
{
serialPort.setSerialPortParams(9600,
SerialPort.DATABITS_8,
SerialPort.STOPBITS_1,
SerialPort.PARITY_NONE);
} catch (UnsupportedCommOperationException e)
{
return InitFail;
}
} catch (NoSuchPortException e)
{
return InitFail;
}
// when successfully open the serial port, create a new serial buffer,
// then
create a thread that consistently accepts incoming signals from
// the serial port. Incoming signals are stored in the serial buffer.
SB = new SerialBuffer();
RT = new ReadSerial(SB, in);
RT.start();
// return success information
return InitSuccess;
}
/**
*
* This function returns a string with a certain length from the incomin
* messages.
*
* @param Length The length of the string to be returned.
*
*/
public String ReadPort(int Length)
{
String Msg;
Msg = SB.GetMsg(Length);
return Msg;
}
/**
*
* This function sends a message through the serial port.
*
* @param Msg The string to be sent.
*
*/
public void WritePort(String Msg)
{
int c;
try
{
for (int i = 0;
i < Msg.length();
i++)
out.write(Msg.charAt(i));
} catch (IOException e) {}
}
/**
*
* This function closes the serial port in use.
*
*/
public void ClosePort()
{
RT.stop();
serialPort.close();
}
}
//package serial;
/**
*
* This class implements the buffer area to store incoming data from the serial
* port.
*
*/
class SerialBuffer
{
private String Content = "";
private String CurrentMsg, TempContent;
private boolean available = false;
private int LengthNeeded = 1;
/**
*
* This function returns a string with a certain length from the incomin
* messages.
*
* @param Length The length of the string to be returned.
*
*/
public synchronized String GetMsg(int Length)
{
LengthNeeded = Length;
notifyAll();
if (LengthNeeded > Content.length())
{
available = false;
while (available == false)
{
try
{
wait();
} catch (InterruptedException e) { }
}
}
CurrentMsg = Content.substring(0, LengthNeeded);
TempContent = Content.substring(LengthNeeded);
Content = TempContent;
LengthNeeded = 1;
notifyAll();
return CurrentMsg;
}
/**
*
* This function stores a character captured from the serial port to the
* buffer area.
*
* @param t The char value of the character to be stored.
*
*/
public synchronized void PutChar(int c)
{
Character d = new Character((char) c);
Content = Content.concat(d.toString());
if (LengthNeeded < Content.length())
{
available = true;
}
notifyAll();
}
}
// package serial;
/**
*
* This class reads message from the specific serial port and save
* the message to the serial buffer.
*
*/
class ReadSerial extends Thread
{
private SerialBuffer ComBuffer;
private InputStream ComPort;
/**
*
* Constructor
*
* @param SB The buffer to save the incoming messages.
* @param Port The InputStream from the specific serial port.
*
*/
public ReadSerial(SerialBuffer SB, InputStream Port)
{
ComBuffer = SB;
ComPort = Port;
}
public void run()
{
int c;
try
{
while (true)
{
c = ComPort.read();
ComBuffer.PutChar(c);
}
} catch (IOException e) {}
}
}







/*
* test.java
*
* Created on 2003年12月12日, 上午10:52
*/
/**
*
* @author king1
*/
//public class test extends java.applet.Applet {

/** Initialization method that will be called after the applet is loaded
* into the browser.
*/
// public void paint (Graphics g) {
// g.drawString("Hello Word",20,20);
// System.out.print("Hello Word");
// }

//}
class main {
public static void main (String[] args)
{
//TOdo
: Add your JAVA codes here
SerialBean SB = new SerialBean(1);
String Msg;
SB.Initialize();
for (int i = 5;
i <= 10;
i++)
{
Msg = SB.ReadPort(i);
SB.WritePort("Reply: " + Msg);
}
SB.ClosePort();
}
}

帮帮忙阿！各位高手。。

写短一些再说？怎么样？

javax.comm.* 包不包含在标准JDK，你要去单独下载，安装到IDE中