java 条码仪

这个是一个JAVA代码的解决方案，但我测试后发现读不到数据，不知道那里有问题，现在还没有解决。

package com;    

/*    
程序文件名称：ReadComm.java    
功能：从串行口COM1中接收数据    
*/    
import java.awt.*;    
import java.awt.event.*;    
import java.io.*;    
import java.util.*;    
import javax.comm.*;    

class R_Frame extends Frame implements Runnable,ActionListener,SerialPortEventListener    
    {    
/* 检测系统中可用的通讯端口类 */    
    static CommPortIdentifier portId;    
/* Enumeration 为枚举型类,在java.util中 */    
    static Enumeration portList;    
    InputStream inputStream;    
/* 声明RS-232串行端口的成员变量 */    
    SerialPort serialPort;    
    Thread readThread;    
    String str="";    
    TextField out_message=new TextField("上面文本框显示接收到的数据");    
    TextArea in_message=new TextArea();    
    Button btnOpen=new Button("打开串口");    
/*建立窗体*/    
    R_Frame()    
    {    
    super("串口接收数据");    
    setSize(200,200);    
    setVisible(true);    
    btnOpen.addActionListener(this);    
    add(out_message,"South");    
    add(in_message,"Center");    
    add(btnOpen,"North");    
    
        
        
    /*获取系统中所有的通讯端口 */    
        portList=CommPortIdentifier.getPortIdentifiers();    
            /* 用循环结构找出串口 */    
        while (portList.hasMoreElements()){    
        /*强制转换为通讯端口类型*/    
        portId=(CommPortIdentifier)portList.nextElement();    
        if(portId.getPortType() == CommPortIdentifier.PORT_SERIAL){    
            if (portId.getName().equals("COM1")) {    
                try {    
            serialPort = (SerialPort) portId.open("ReadComm", 2000);    
            out_message.setText("已打开端口COM1 ,正在接收数据..... ");    
            }    
        catch (PortInUseException e) { }    

        /*设置串口监听器*/    
        try {    
        serialPort.addEventListener(this);    
        }    
        catch (TooManyListenersException e) { }    
        /* 侦听到串口有数据,触发串口事件*/    
        serialPort.notifyOnDataAvailable(true);    
        } //if end    
        } //if end    
        } //while end    
        readThread = new Thread(this);    
        readThread.start(); //线程负责每接收一次数据休眠20秒钟    
        } //R_Frame() end    


    
    /*点击按扭所触发的事件：打开串口,并监听串口. */    
public void actionPerformed(ActionEvent event)    
    {    
        /*获取系统中所有的通讯端口 */    
        portList=CommPortIdentifier.getPortIdentifiers();    
        /* 用循环结构找出串口 */    
        while (portList.hasMoreElements()){    
        /*强制转换为通讯端口类型*/    
        portId=(CommPortIdentifier)portList.nextElement();    
        if(portId.getPortType() == CommPortIdentifier.PORT_SERIAL){    
        if (portId.getName().equals("COM1")) {    
        try {    
        serialPort = (SerialPort) portId.open("ReadComm", 2000);    
        out_message.setText("已打开端口COM1 ,正在接收数据..... ");    
        }    
        catch (PortInUseException e) { }    

    /*设置串口监听器*/    
        try {    
        serialPort.addEventListener(this);    
        }    
        catch (TooManyListenersException e) { }    
    /* 侦听到串口有数据,触发串口事件*/    
        serialPort.notifyOnDataAvailable(true);    
        } //if end    
        } //if end    
        } //while end    
        readThread = new Thread(this);    
        readThread.start(); //线程负责每接收一次数据休眠20秒钟    
        } //actionPerformed() end    

        /*接收数据后休眠20秒钟*/    
public void run() {    
        try {    
        Thread.sleep(20000);    
        }    
    catch (InterruptedException e) { }    
        } //run() end    

        /*串口监听器触发的事件，设置串口通讯参数，读取数据并写到文本区中*/    
public void serialEvent(SerialPortEvent event) {    
    /*设置串口通讯参数：波特率、数据位、停止位、奇偶校验*/    
        try {    
        serialPort.setSerialPortParams(9600,    
        SerialPort.DATABITS_8,    
        SerialPort.STOPBITS_1,    
        SerialPort.PARITY_NONE);    
        }    
        catch (UnsupportedCommOperationException e) {}    
            byte[] readBuffer = new byte[20];    
        try {    
            inputStream = serialPort.getInputStream();    
        }    
        catch (IOException e){    
}    
        try {    

        while (inputStream.available() > 0)    
        {    
            int numBytes = inputStream.read(readBuffer);    
                } //while end    
            str=new String(readBuffer);    
        /*接收到的数据存放到文本区中*/    
            in_message.append(str+"\n");    
            }    
            catch (IOException e){    
            }    
            } //serialEvent() end    
        } //类R_Frame end    

        public class ReadComm    
        {    
public static void main(String args[])    
        {    
        /* 实例化接收串口数据的窗体类 */    
        R_Frame R_win=new R_Frame();    
        /* 定义窗体适配器的关闭按钮功能 */    
        R_win.addWindowListener(new WindowAdapter()    
        {    
        public void windowClosing(WindowEvent e)    
        {    
        System.exit(0);    
        }    
    });    
        R_win.pack();    
    }    
}    

 

 

 

这个是在web页面上的实现，修改了下现在可以读到数据，但这个需要注册MSCOMM组件，还算比较理想吧！

<%@ page contentType="text/html; charset=gb2312" language="java"    %>    
<html>    
<head>    
<title>JavaScript MSCOMM32.OCX </title>    

<SCRIPT ID=clientEventHandlersJS LANGUAGE=javascript>    
//重写 mscomm 控件的唯一事件处理代码    
function MSComm1_OnComm()    
{    
var len=0;    
if(MSComm1.CommEvent==1)//如果是发送事件    
{    
    window.alert("请读条码");//这句正常，说明发送成功了    
}    
else if(MSComm1.CommEvent==2)//如果是接收事件    
{    
        document.form1.txtReceive.value=document.form1.txtReceive.value + MSComm1.Input;    
}    

}    
</SCRIPT>    

<SCRIPT LANGUAGE=javascript FOR=MSComm1 EVENT=OnComm>    
// MSComm1控件每遇到 OnComm 事件就调用 MSComm1_OnComm()函数    
MSComm1_OnComm()    
</SCRIPT>    


<script language="JavaScript" type="text/JavaScript">    
//打开端口并发送命令程序    
function OpenPort()    
{    
if(MSComm1.PortOpen==false)    
{    
MSComm1.PortOpen=true;    
MSComm1.Output="R";//发送命令    
//window.alert("成功发出命令！");
}    
else    
{    
    window.alert ("已经开始接收数据!");    
}    
}    
</script>    

</head>    
<OBJECT CLASSID="clsid:648A5600-2C6E-101B-82B6-000000000014" id=MSComm1 codebase="MSCOMM32.OCX" type="application/x-oleobject"    
style="LEFT: 54px; TOP: 14px" >    
<PARAM NAME="CommPort" VALUE="1">    
<PARAM NAME="DTREnable" VALUE="1">    
<PARAM NAME="Handshaking" VALUE="0">    
<PARAM NAME="InBufferSize" VALUE="1024">    
<PARAM NAME="InputLen" VALUE="0">    
<PARAM NAME="NullDiscard" VALUE="0">    
<PARAM NAME="OutBufferSize" VALUE="512">    
<PARAM NAME="ParityReplace" VALUE="?">    
<PARAM NAME="RThreshold" VALUE="1">    
<PARAM NAME="RTSEnable" VALUE="1">    
<PARAM NAME="SThreshold" VALUE="2">    
<PARAM NAME="EOFEnable" VALUE="0">    
<PARAM NAME="InputMode" VALUE="0">    

<PARAM NAME="DataBits" VALUE="8">    
<PARAM NAME="StopBits" VALUE="1">    
<PARAM NAME="BaudRate" VALUE="9600">    
<PARAM NAME="Settings" VALUE="9600,N,8,1">    
</OBJECT>    

<body>    
<form name="form1">    
<input type="button" name="Submit" value="提交" onClick="OpenPort()">    
<input type="text" name="txtReceive" size=50 value="">    
</form>    
</body>    
</html>