java的串口通信
java串口通信數據緩存要清空步驟：
找到Java的安裝目錄（默認為C:Program FilesJava）選擇當前使用的jre版本，如果用的版本為jre5則進入jre5文件夾，如果用的版本為jre6則進入jre6文件夾。在該文件夾下進入bin文件夾。雙擊打開文件javacpl.exe
在常規選項中的臨時Internet文件點擊「設置」按鈕再點擊「刪除文件」按鈕,刪除所有的臨時文件。
刪除完緩存之後，需要關閉所有瀏覽器。再次打開瀏覽器進入虛擬實驗系統即可。
❷ java串口通信
java.comm可以在XP下使用，我用JAVA寫過串口程序
下載了comm.jar開發包後，與之一起的還有兩個重要的文件，win32com.dll和javax.comm.properties。
1 comm.jar提供了通訊用的java API。
2 win32com.dll提供了供comm.jar調用的本地驅動介面。
3 javax.comm.properties是這個驅動的類配置文件。
首先 將comm.jar復制到<JRE_HOME>\lib\ext目錄。
接著 將win21com.dll復制到你的RS232應用程序運行的目錄，即user.dir。
最後 將javax.comm.properties復制到<JRE_HOME>\lib目錄。
我在Eclipse3.2+JDK1.6開發的時候，在項目中包含comm.jar和win32com.dll
❸ 基於JAVA的串口通信
串口通信 我有源代碼
圖像顯示，JFreeChart
❹ java 串口通信
這里的Byte並不是Java中八種基本類型中的byte，作為數據類型，byte是要表示負數的，但作為串口值，並不需要負數，所以這里的Byte最大值可以表示255
❺ jsp，java串口通信的問題
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);//設置埠號2
String Msg = "AD 01 0D";//發送命令
SB.Initialize(9600);//設置波率
SB.WritePort(Msg);//發送命令
/* for (int i = 5; i < 10; i++) {
System.out.println( SB.ReadPort(3));//設置讀取個數
}
*/
String readdata = SB.ReadPort("0D",4000);//讀取以OD結束的數據,4000ms沒有數據就返回空
if (readdata.length() > 0) { //System.out.println(readdata.length());//如果有讀到數據
System.out.println(readdata);//如果有讀到數據
}
while (readdata.length() < 1 && state) {//如果沒有讀到數據
readdata = SB.ReadPort("0D",4000);
System.out.println(readdata);
if (System.currentTimeMillis() - curTime > serialtime) {
state = false;//設置讀取錯誤超時
}
System.out.println("readdaa:" + state);
System.out.println(System.currentTimeMillis() - curTime);
}
if (!state) {
System.out.println("數據讀取超時");
}
SB.ClosePort();//關閉連接
}
}
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());//設置埠號2
t=SB.Initialize(getComrate());//設置波率
if(t>0){
SB.WritePort(getSendtxt());//發送命令
if (hasreturn) {
String readdata = SB.ReadPort(getEndtxt(), getTimeout());//讀取以OD結束的數據,4000ms沒有數據就返回空
if (readdata.length() > 0) { //System.out.println(readdata.length());//如果有讀到數據
System.out.println(readdata);//如果有讀到數據
}
while (readdata.length() < 1 && state) {//如果沒有讀到數據
readdata = SB.ReadPort(getEndtxt(), getTimeout());
System.out.println(readdata);
if (System.currentTimeMillis() - curTime > serialtime) {
state = false;//設置讀取錯誤超時
}
System.out.println("readdaa:" + state);
System.out.println(System.currentTimeMillis() - curTime);
}
if (!state) {
System.out.println("數據讀取超時");
setMassage("數據讀取超時");
}
setRecivetxt(readdata);
setPstate(state);
}
SB.ClosePort();//關閉連接
}else{
System.out.println("埠號出現錯誤");
setMassage("埠號出現錯誤");
}
}
/**
* @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";//發送命令
SerialBean SB = new SerialBean(10);//設置埠號2
SB.Initialize(9600);//設置波率
SB.WritePort(Msg);//發送命令
/* for (int i = 5; i < 10; i++) {
System.out.println( SB.ReadPort(3));//設置讀取個數
}
*/
String readdata = SB.ReadPort("0D",4000);//讀取以OD結束的數據
if (readdata.length() > 0) { //System.out.println(readdata.length());//如果有讀到數據
System.out.println(readdata);//如果有讀到數據
}
while (readdata.length() < 1 && state) {//如果沒有讀到數據
readdata = SB.ReadPort("0D",4000);
System.out.println(readdata);
out.println(readdata);
if (System.currentTimeMillis() - curTime > serialtime) {
state = false;//設置讀取錯誤超時
}
System.out.println("readdaa:" + state);
System.out.println(System.currentTimeMillis() - curTime);
}
if (!state) {
System.out.println("數據讀取超時");
out.println("數據讀取超時");
}
SB.ClosePort();//關閉連接
} 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進制字元串轉換成位元組數組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;
}
/**
* 把位元組數組轉換成16進制字元串
* @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，讀取和發送數據
publicstaticvoidprocess(){
try{
EnumerationportList=CommPortIdentifier.getPortIdentifiers();
while(portList.hasMoreElements())
{
CommPortIdentifierportId=(CommPortIdentifier)portList.nextElement();
if(portId.getPortType()==CommPortIdentifier.PORT_SERIAL)//如果埠類型是串口則判斷名稱
{
if(portId.getName().equals("COM1")){//如果是COM1埠則退出循環
break;
}else{
portId=null;
}
}
}
SerialPortserialPort=(SerialPort)portId.open("Serial_Communication",1000);//打開串口的超時時間為1000ms
serialPort.setSerialPortParams(9600,SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);//設置串口速率為9600，數據位8位，停止位1們，奇偶校驗無
InputStreamin=serialPort.getInputStream();//得到輸入流
OutputStreamout=serialPort.getOutputStream();//得到輸出流
//進行輸入輸出操作
//操作結束後
in.close();
out.close();
serialPort.close();//關閉串口
}catch(PortInUseExceptione){
e.printStackTrace();
}catch(){
e.printStackTrace();
}catch(IOExceptione){
e.printStackTrace();
}
}
❼ 在java的web程序中怎麼使用串口通訊
最近在做java串口通訊，主要是用個人電腦通過串口從RS485讀取數據，並通過crc循環冗餘校驗，把接收正確的數據解析，插入資料庫mysql，並用SSH技術把資料庫數據以表格以及圖表形式顯示
思路：
1.為了從RS485讀取數據，由於暫時沒有硬體設備，系統是win7，故採用Virtual Serial Port Drive（VSPD）這塊虛擬串口軟體代替。並下載sscom32.exe模擬串口通信軟體。
2. 要想實現串口通信，用Java實現串口通信（windows系統下），需要用到sun提供的串javacomm20-win32.zip。其中要用到三個文件，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 兩個地方都要放
jre/lib(也就是在JAVA文件夾下的jre),JAVA_HOME/jre/lib下
這個配置在我電腦上測試成功，也許不需要這樣麻煩。注意的是，如果你使用myeclipse，因為它自帶jre，你需要在它所在的jre相應位置放dll以及properties文件。
是不是感覺這個很麻煩，還有windows的限制。後來我們下載rxtx這款開源包代替了剛才的comm。不僅windows下可以，linux下也可以。使用方法很簡單，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放到它自帶的jre里。
3.新建eclipse工程，添加comm.jar或者RXTXcomm.jar包。因為javacomm20-win32.zip包里有樣例SimpleRead.java，可以通過這個例子測試串口是否正確
4.接收數據正確後，根據傳送接收雙方的協議，採用CRC循環校驗，根據傳輸的一方的校驗函數判定是否是正確傳輸
5.把正確結束的數據解析，查看自己指定的通訊規則，然後解析
6.插入資料庫，jdbc插入
7.數據統計，定時統計每小時，每天，每月，每年的平均值，採用quartz服務來實現。
8.建立web工程，採用hibernate3，spring3，dwr技術把資料庫數據動態顯示，圖表採用jfreechart，以及AJAX的運用
❽ 求助：java串口通信問題
你myeclipse和tomcat對應的java運行環境不一樣，你要先確定tomcat運行的的jre是哪一個，然後再配置串口環境。