java的串口通信
java串口通信数据缓存要清空步骤：
找到Java的安装目录（默认为C:Program FilesJava）选择当前使用的jre版本，如果用的版本为jre5则进入jre5文件夹，如果用的版本为jre6则进入jre6文件夹。在该文件夹下进入bin文件夹。双击打开文件javacpl.exe
在常规选项中的临时Internet文件点击“设置”按钮再点击“删除文件”按钮,删除所有的临时文件。
删除完缓存之后，需要关闭所有浏览器。再次打开浏览器进入虚拟实验系统即可。
❷ java串口通信
java.comm可以在XP下使用，我用JAVA写过串口程序
下载了comm.jar开发包后，与之一起的还有两个重要的文件，win32com.dll和javax.comm.properties。
1 comm.jar提供了通讯用的java API。
2 win32com.dll提供了供comm.jar调用的本地驱动接口。
3 javax.comm.properties是这个驱动的类配置文件。
首先 将comm.jar复制到<JRE_HOME>\lib\ext目录。
接着 将win21com.dll复制到你的RS232应用程序运行的目录，即user.dir。
最后 将javax.comm.properties复制到<JRE_HOME>\lib目录。
我在Eclipse3.2+JDK1.6开发的时候，在项目中包含comm.jar和win32com.dll
❸ 基于JAVA的串口通信
串口通信 我有源代码
图像显示，JFreeChart
❹ java 串口通信
这里的Byte并不是Java中八种基本类型中的byte，作为数据类型，byte是要表示负数的，但作为串口值，并不需要负数，所以这里的Byte最大值可以表示255
❺ jsp，java串口通信的问题
可以,使用comm,jar
class SerialExample {
public static void main(String[] args) {
//TO DO: Add your JAVA codes here
long curTime = System.currentTimeMillis();
long serialtime = 8000;
boolean state = true;
SerialBean SB = new SerialBean(2);//设置端口号2
String Msg = "AD 01 0D";//发送命令
SB.Initialize(9600);//设置波率
SB.WritePort(Msg);//发送命令
/* for (int i = 5; i < 10; i++) {
System.out.println( SB.ReadPort(3));//设置读取个数
}
*/
String readdata = SB.ReadPort("0D",4000);//读取以OD结束的数据,4000ms没有数据就返回空
if (readdata.length() > 0) { //System.out.println(readdata.length());//如果有读到数据
System.out.println(readdata);//如果有读到数据
}
while (readdata.length() < 1 && state) {//如果没有读到数据
readdata = SB.ReadPort("0D",4000);
System.out.println(readdata);
if (System.currentTimeMillis() - curTime > serialtime) {
state = false;//设置读取错误超时
}
System.out.println("readdaa:" + state);
System.out.println(System.currentTimeMillis() - curTime);
}
if (!state) {
System.out.println("数据读取超时");
}
SB.ClosePort();//关闭连接
}
}
public class SerialBuffer {
Convents cv = new Convents();
private String Content = "";
private String CurrentMsg, TempContent;
private boolean available = false;
private int LengthNeeded = 1;
String str = "";
byte b;
/**
*
* This function returns a string with a certain length from the incoming
* messages.
*
* @param Length The length of the string to be returned.
*
*/
public synchronized String GetMsg(int Length) {
LengthNeeded = Length;
long timeout=2000;
long curtime=System.currentTimeMillis();
notifyAll();
if (LengthNeeded > Content.length()) {
available = false;
while (available == false) {
try {
if(System.currentTimeMillis()-curtime<timeout) wait();
} catch (InterruptedException e) {
}
}
}
CurrentMsg = Content.substring(0, LengthNeeded);
TempContent = Content.substring(LengthNeeded);
Content = TempContent;
LengthNeeded = 1;
notifyAll();
return CurrentMsg;
}
public synchronized String GetMsg(String endstring,long timeout) {
LengthNeeded =Content.indexOf(endstring);
notifyAll();
if (LengthNeeded < 0) {
available = false;
while (available == false) {
try {
wait(timeout);
available=true;
} catch (InterruptedException e) {
}
}
return "";
}
if (LengthNeeded > 0) {
CurrentMsg = Content.substring(0, LengthNeeded+endstring.length());
TempContent = Content.substring(LengthNeeded+endstring.length());
Content = TempContent;
}
LengthNeeded = -1;
notifyAll();
return CurrentMsg;
}
public synchronized void PutChar(int c) {
Content = Content.concat(cv.byteToHexString(c));
if (LengthNeeded < Content.length() && Content.length() > 0) {
available = true;
}
notifyAll();
}
}
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package common.serial;
/**
*
* @author Jason
*/
import java.io.*;
import java.util.*;
import javax.comm.*;
import common.code.Convents;
public class SerialBean {
Convents cv=new Convents();
String PortName = "";
CommPortIdentifier portId = null;
SerialPort serialPort = null;
OutputStream out;
InputStream in;
SerialBuffer SB;
ReadSerial RT;
int rate=9600;
String endstring ="";
long timeout=2000;
public SerialBean(int PortID) {
PortName = "COM" + PortID;
}
public int Initialize(int rate) {
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(rate,
SerialPort.DATABITS_8,
SerialPort.STOPBITS_1,
SerialPort.PARITY_NONE);
} catch ( e) {
return InitFail;
}
} catch (NoSuchPortException e) {
return InitFail;
}
SB = new SerialBuffer();
RT = new ReadSerial(SB, in);
RT.start();
return InitSuccess;
}
public String ReadPort(int Length) {
String Msg;
Msg = SB.GetMsg(Length);
return Msg;
}
public String ReadPort(String endstring,long timeout) {
String Msg;
Msg = SB.GetMsg(endstring,timeout);
return Msg;
}
public void WritePort(String Msg) {
try {
out.write(cv.hexStringToByte(Msg));
} catch (IOException e) {
}
}
public void ClosePort() {
serialPort.close();
}
}
package common.serial;
import java.io.*;
public class ReadSerial extends Thread {
private SerialBuffer ComBuffer;
private InputStream ComPort;
char[] ch;
public ReadSerial(SerialBuffer SB, InputStream Port) {
ComBuffer = SB;
ComPort = Port;
}
@Override
public void run() {
int c;
try {
while (true) {
c=ComPort.read();
ComBuffer.PutChar(c);
}
} catch (IOException e) {
}
}
}
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package common.serial;
/**
*
* @author Administrator
*/
public class PortOpreate {
private String sendtxt="";
private String recivetxt="";
private int comid = 1;
private int comrate = 9600;
private int timeout = 4000;
private long waittime = 13000;
private String endtxt = "0D";
private boolean pstate=false;
private String massage="";
public void PortOpreate(boolean hasreturn) {
long curTime = System.currentTimeMillis();
long serialtime = getWaittime();
boolean state = true;
int t=0;
SerialBean SB = new SerialBean(getComid());//设置端口号2
t=SB.Initialize(getComrate());//设置波率
if(t>0){
SB.WritePort(getSendtxt());//发送命令
if (hasreturn) {
String readdata = SB.ReadPort(getEndtxt(), getTimeout());//读取以OD结束的数据,4000ms没有数据就返回空
if (readdata.length() > 0) { //System.out.println(readdata.length());//如果有读到数据
System.out.println(readdata);//如果有读到数据
}
while (readdata.length() < 1 && state) {//如果没有读到数据
readdata = SB.ReadPort(getEndtxt(), getTimeout());
System.out.println(readdata);
if (System.currentTimeMillis() - curTime > serialtime) {
state = false;//设置读取错误超时
}
System.out.println("readdaa:" + state);
System.out.println(System.currentTimeMillis() - curTime);
}
if (!state) {
System.out.println("数据读取超时");
setMassage("数据读取超时");
}
setRecivetxt(readdata);
setPstate(state);
}
SB.ClosePort();//关闭连接
}else{
System.out.println("端口号出现错误");
setMassage("端口号出现错误");
}
}
/**
* @return the sendtxt
*/
public String getSendtxt() {
return sendtxt;
}
/**
* @param sendtxt the sendtxt to set
*/
public void setSendtxt(String sendtxt) {
this.sendtxt = sendtxt;
}
/**
* @return the recivetxt
*/
public String getRecivetxt() {
return recivetxt;
}
/**
* @param recivetxt the recivetxt to set
*/
public void setRecivetxt(String recivetxt) {
this.recivetxt = recivetxt;
}
/**
* @return the comid
*/
public int getComid() {
return comid;
}
public void setComid(int comid) {
this.comid = comid;
}
public int getComrate() {
return comrate;
}
public void setComrate(int comrate) {
this.comrate = comrate;
}
public int getTimeout() {
return timeout;
}
public void setTimeout(int timeout) {
this.timeout = timeout;
}
public long getWaittime() {
return waittime;
}
public void setWaittime(long waittime) {
this.waittime = waittime;
}
public String getEndtxt() {
return endtxt;
}
public void setEndtxt(String endtxt) {
this.endtxt = endtxt;
}
public boolean isPstate() {
return pstate;
}
public void setPstate(boolean pstate) {
this.pstate = pstate;
}
public String getMassage() {
return massage;
}
public void setMassage(String massage) {
this.massage = massage;
}
}
package common.serial;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class PortOperatorServlet extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
try {
long curTime = System.currentTimeMillis();
long serialtime = 8000;
boolean state = true;
String Msg = "AD 01 0D";//发送命令
SerialBean SB = new SerialBean(10);//设置端口号2
SB.Initialize(9600);//设置波率
SB.WritePort(Msg);//发送命令
/* for (int i = 5; i < 10; i++) {
System.out.println( SB.ReadPort(3));//设置读取个数
}
*/
String readdata = SB.ReadPort("0D",4000);//读取以OD结束的数据
if (readdata.length() > 0) { //System.out.println(readdata.length());//如果有读到数据
System.out.println(readdata);//如果有读到数据
}
while (readdata.length() < 1 && state) {//如果没有读到数据
readdata = SB.ReadPort("0D",4000);
System.out.println(readdata);
out.println(readdata);
if (System.currentTimeMillis() - curTime > serialtime) {
state = false;//设置读取错误超时
}
System.out.println("readdaa:" + state);
System.out.println(System.currentTimeMillis() - curTime);
}
if (!state) {
System.out.println("数据读取超时");
out.println("数据读取超时");
}
SB.ClosePort();//关闭连接
} finally {
out.close();
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
public String getServletInfo() {
return "Short description";
}
}
package common.code;
public final class Convents {
public final static char[] BToA = "0123456789abcdef".toCharArray();
/**
* 把16进制字符串转换成字节数组A1 01 0D
* @param hex
* @return
*/
public byte[] hexStringToByte(String hex) {
String str[] = hex.split(" ");
int len = str.length;
byte[] result = new byte[len];
char[] achar = hex.toCharArray();
for (int i = 0; i < len; i++) {
result[i] = (byte) (toByte(str[i].charAt(0)) * 16 + toByte(str[i].charAt(1)));
}
return result;
}
private static byte toByte(char c) {
byte b = (byte) ("0123456789ABCDEF".indexOf(c));
return b;
}
/**
* 把字节数组转换成16进制字符串
* @param bArray
* @return
*/
public String byteToHexString(int b){
String st="";
st=Integer.toHexString(b);
if (st.length() < 2) {
st="0"+Integer.toHexString(b).toUpperCase()+" ";
} else {
st=Integer.toHexString(b).toUpperCase()+" ";
}
return st;
}
public String bytesToHexString(byte[] bArray) {
StringBuffer sb = new StringBuffer(bArray.length);
String sTemp;
for (int i = 0; i < bArray.length; i++) {
sTemp = Integer.toHexString(bArray[i]).toUpperCase();
}
return sb.toString();
}
}
❻ java串口，读取和发送数据
publicstaticvoidprocess(){
try{
EnumerationportList=CommPortIdentifier.getPortIdentifiers();
while(portList.hasMoreElements())
{
CommPortIdentifierportId=(CommPortIdentifier)portList.nextElement();
if(portId.getPortType()==CommPortIdentifier.PORT_SERIAL)//如果端口类型是串口则判断名称
{
if(portId.getName().equals("COM1")){//如果是COM1端口则退出循环
break;
}else{
portId=null;
}
}
}
SerialPortserialPort=(SerialPort)portId.open("Serial_Communication",1000);//打开串口的超时时间为1000ms
serialPort.setSerialPortParams(9600,SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);//设置串口速率为9600，数据位8位，停止位1们，奇偶校验无
InputStreamin=serialPort.getInputStream();//得到输入流
OutputStreamout=serialPort.getOutputStream();//得到输出流
//进行输入输出操作
//操作结束后
in.close();
out.close();
serialPort.close();//关闭串口
}catch(PortInUseExceptione){
e.printStackTrace();
}catch(){
e.printStackTrace();
}catch(IOExceptione){
e.printStackTrace();
}
}
❼ 在java的web程序中怎么使用串口通讯
最近在做java串口通讯，主要是用个人电脑通过串口从RS485读取数据，并通过crc循环冗余校验，把接收正确的数据解析，插入数据库mysql，并用SSH技术把数据库数据以表格以及图表形式显示
思路：
1.为了从RS485读取数据，由于暂时没有硬件设备，系统是win7，故采用Virtual Serial Port Drive（VSPD）这块虚拟串口软件代替。并下载sscom32.exe模拟串口通信软件。
2. 要想实现串口通信，用Java实现串口通信（windows系统下），需要用到sun提供的串javacomm20-win32.zip。其中要用到三个文件，配置如下：
comm.jar放置到 JAVA_HOME/jre/lib/ext;
win32com.dll放置到 JAVA_HOME/bin;
javax.comm.properties 两个地方都要放
jre/lib(也就是在JAVA文件夹下的jre),JAVA_HOME/jre/lib下
这个配置在我电脑上测试成功，也许不需要这样麻烦。注意的是，如果你使用myeclipse，因为它自带jre，你需要在它所在的jre相应位置放dll以及properties文件。
是不是感觉这个很麻烦，还有windows的限制。后来我们下载rxtx这款开源包代替了刚才的comm。不仅windows下可以，linux下也可以。使用方法很简单，配置如下：
RXTXcomm.jar放到JAVA_HOME/jre/lib/ext
rxtxSerial.dll放到JAVA_HOME/bin
如果你使用myeclipse工具，你需要把rxtxSerial.dll放到它自带的jre里。
3.新建eclipse工程，添加comm.jar或者RXTXcomm.jar包。因为javacomm20-win32.zip包里有样例SimpleRead.java，可以通过这个例子测试串口是否正确
4.接收数据正确后，根据传送接收双方的协议，采用CRC循环校验，根据传输的一方的校验函数判定是否是正确传输
5.把正确结束的数据解析，查看自己指定的通讯规则，然后解析
6.插入数据库，jdbc插入
7.数据统计，定时统计每小时，每天，每月，每年的平均值，采用quartz服务来实现。
8.建立web工程，采用hibernate3，spring3，dwr技术把数据库数据动态显示，图表采用jfreechart，以及AJAX的运用
❽ 求助：java串口通信问题
你myeclipse和tomcat对应的java运行环境不一样，你要先确定tomcat运行的的jre是哪一个，然后再配置串口环境。