java 串口通信读取电子秤
1、在网上下载RXTXcomm.jar、rxtxParallel.dll、rxtxSerial.dll，有32位和64位的版本
2、把rxtxParallel.dll、rxtxSerial.dll拷贝到：C:\WINDOWS\system32下。
3、把RXTXcomm.jar、rxtxParallel.dll、rxtxSerial.dll拷贝到 jdk1.8.0_131\jre\lib\ext下；
如：C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext
4、替换采样程序目录下的libs文件夹下的 RXTXcomm.jar
//打开串口 根据串口名、波特率
private static void openSerialPort()
{
//读取可用端口
commList = findPort();
// 检查是否有可用串口，有则加入选项中
if (commList == null || commList.size() < 1) {
System.out.println("没有搜索到有效串口！");
WriteLog("没有搜索到有效串口", "", "");
} else {
String CanUserCom = "";
for (String s : commList) {
CanUserCom += " " + s;
}
WriteLog("搜索到有效串口：" + CanUserCom, "", "");
WriteLog("连接电子秤时请确认波特率、数据位、停止位、奇偶校验等信息是否匹配！", "", "");
}
// 检查串口名称是否获取正确
if (Common.CommName == null || Common.CommName.equals(""))
{
WriteLog("串口设置为空，请检查配置","","");
System.out.println("串口设置为空，请检查配置！");
}
else
{
WriteLog(Common.CommName + "打开串口中、波特率："+Common.BaudRate+"、数据位："+Common.DataBits+"、停止为："+Common.StopBits+"、奇偶校验："+Common.CheckChar, "", "");
String commName = Common.CommName;//串口
int baudrate = Integer.valueOf(Common.BaudRate); //波特率
int DataBits = Integer.valueOf(Common.DataBits); //数据位、
int StopBits = Integer.valueOf(Common.StopBits); //停止为
//奇偶校验位数据转换
//无：0、奇数：1、偶数：2
int ParityBits = 0; //奇偶校验
switch (Common.ParityBits)
{
case "无":
ParityBits = 0;
break;
case "奇":
ParityBits = 1;
break;
case "偶":
ParityBits = 2;
break;
}
try
{
serialport = openPort(commName, baudrate,DataBits,StopBits,ParityBits);
if (serialport != null)
{
WriteLog(commName + "串口已打开", "", "");
System.out.println("串口已打开" + "\r\n");
WriteFromPort(serialport);
}
} catch (SerialPortParameterFailure e) {
e.printStackTrace();
} catch (NotASerialPort e) {
e.printStackTrace();
} catch (NoSuchPort e) {
e.printStackTrace();
}
catch (PortInUse e)
{
e.printStackTrace();
System.out.println("串口已被占用！");
WriteLog(commName+"串口已被占用","","");
JOptionPane.showMessageDialog(null, "打开失败！串口已被占用或者软件已打开。", "提示", JOptionPane.ERROR_MESSAGE);
logger.error("串口已被占用：" + e.getMessage(), e);
}
}
try {
addListener(serialport, new SerialListener());
} catch (TooManyListeners e) {
e.printStackTrace();
}
}
//从串口读取数据
/**
* 从串口读取数据
*
* @param serialPort
* 当前已建立连接的SerialPort对象
* @return 读取到的数据
* @throws ReadDataFromSerialPortFailure
* 从串口读取数据时出错
* @throws SerialPortInputStreamCloseFailure
* 关闭串口对象输入流出错
*/
public static byte[] readFromPort(SerialPort serialPort) throws ReadDataFromSerialPortFailure,SerialPortInputStreamCloseFailure {
InputStream in = null;
byte[] bytes = null;
byte[] bytesAll = new byte[100];
int bytesLenght = 0;
try {
in = serialPort.getInputStream();
try {
// 获取buffer里的数据长度
int bufflenth = in.available();
while (bufflenth != 0) {
// 初始化byte数组为buffer中数据的长度
bytes = new byte[bufflenth];
in.read(bytes);
bufflenth = in.available();
}
//System.err.println("in.available="+in.available());
}catch(Exception ex)
{}
} catch (IOException e) {
logger.error("从串口读取数据：" + e.getMessage(), e);
throw new ReadDataFromSerialPortFailure();
} finally {
try {
if (in != null) {
in.close();
in = null;
}
} catch (IOException e) {
throw new SerialPortInputStreamCloseFailure();
}
}
return bytes;
}
//向串口写数
public static void WriteFromPort(SerialPort serialPort) {
try {
//获取串口的输出流对象
OutputStream outputStream = serialPort.getOutputStream();
//通过串口的输出流向串口写数据
outputStream.write(new byte[]{'1'});
outputStream.flush();
//关闭输出流
outputStream.close();
System.out.println("发送数据1");
} catch (Exception e) {
logger.error("从串口写数据：" + e.getMessage(), e);
}
}
//处理监控到的串口事件
private static class SerialListener implements SerialPortEventListener {
//处理监控到的串口事件
public void serialEvent(SerialPortEvent serialPortEvent) {
switch (serialPortEvent.getEventType()) {
case SerialPortEvent.BI: // 10 通讯中断
System.err.println("与串口设备通讯中断");
WriteLog("与串口设备通讯中断","","");
break;
case SerialPortEvent.OE: // 7 溢位（溢出）错误
case SerialPortEvent.FE: // 9 帧错误
case SerialPortEvent.PE: // 8 奇偶校验错误
case SerialPortEvent.CD: // 6 载波检测
case SerialPortEvent.CTS: // 3 清除待发送数据
case SerialPortEvent.DSR: // 4 待发送数据准备好了
case SerialPortEvent.RI: // 5 振铃指示
case SerialPortEvent.OUTPUT_BUFFER_EMPTY: // 2 输出缓冲区已清空
break;
case SerialPortEvent.DATA_AVAILABLE: // 1 串口存在可用数据
byte[] data = null;
try {
if (serialport == null)
{
//System.err.println("串口对象为空！监听失败！");
WriteLog("串口对象为空！监听失败！", "", "");
System.err.println("串口对象为空！监听失败");
} else {
// 读取串口数据
data = readFromPort(serialport);
if(Portdata==null || Portdata.equals(""))
Portdata = new String(data);
else
Portdata += new String (data);
Portdata = Portdata.replaceAll("\r\n","");
ShowPortdata = Portdata;
System.err.println("data="+Portdata);
switch (Common.EquipType)
{
case "沈阳龙腾JD4000":
//波特率：1200 数据位8 校验位：无 停止位：1 起始为1 输出码 ASCII码 空格开始 S结束 返回数据： +200.34 GS 或者 -0.05 GS
int SIndex = Portdata.lastIndexOf("S");
int FIndex = Portdata.lastIndexOf(" ");
int FIndexZ = Portdata.lastIndexOf("+");
if(FIndex>=0 && SIndex>1)
{
String WeightTemp = Portdata;
String FirstChar = "+";
if(FIndexZ>0)
FirstChar = WeightTemp.substring(FIndexZ,FIndexZ+1); //符号
int GIndex = WeightTemp.indexOf("G");
String Number = WeightTemp.substring(FIndexZ+1,GIndex);
if(FirstChar.equals("+"))
Weight = Number; //将样重信息赋值给全局变量
if(Weight.lastIndexOf("-")==0)
Weight = "0.0";
Portdata = ""; //取数成功后清空数据
}
break;
case "上海耀华XK3190":
//wn都存在
//wn00000.60kg
//存在此种情况只有w没有n：wn00000.60kgwn00000.60kgwn00000.60kgw00000.60kg0000.60kgw00000.60kgw00000.60kgw00000.60kgw00000.60kg
//此时去掉n后面的无效数据,重新获取n 和 k 的位置
if(Portdata!="")
{
int LastFirstGIndex = Portdata.lastIndexOf("g");
if(LastFirstGIndex>0)
{
Portdata = Portdata.substring(0, LastFirstGIndex); //将末尾的不符合的数据截取掉
int LastFirstKIndex = Portdata.lastIndexOf("k");
if (LastFirstKIndex > 0) {
String WeightTemp = Portdata.substring(LastFirstKIndex - 8, LastFirstKIndex);
//WriteLog("WeightTemp="+WeightTemp, "", "");
PortList.add(WeightTemp);
Weight = GetStableWeight();
Portdata = ""; //取数成功后清空数据
}
}
}
break;
case "博图BT419W":
//ST NT 000313.6 gST NT 000313.6 gST NT 000313.6 gST NT 000313.7 gST NT 000313.7 gST NT 000313.7 gST NT 000313.7 g
if(Portdata!="")
{
int LastFirstGIndex = Portdata.lastIndexOf("g");
if(LastFirstGIndex>0)
{
Portdata = Portdata.substring(0, LastFirstGIndex); //将末尾的不符合的数据截取掉
int LastFirstKIndex = Portdata.lastIndexOf(" ");
if (LastFirstKIndex > 0) {
String WeightTemp = Portdata.substring(LastFirstKIndex - 8, LastFirstKIndex);
PortList.add(WeightTemp);
Weight = GetStableWeight();
Portdata = ""; //取数成功后清空数据
}
}
}
break;
case "自定义配置":
if(Portdata!="")
{
int LastFirstGIndex = Portdata.lastIndexOf(Common.EndChar);
if(LastFirstGIndex>0)
{
Portdata = Portdata.substring(0, LastFirstGIndex); //将末尾的不符合的数据截取掉
int LastFirstKIndex = Portdata.lastIndexOf(Common.NumberAfterChar);
if (LastFirstKIndex > 0)
{
String WeightTemp = "";
if(Common.symbol.equals(""))
{
WeightTemp = Portdata.substring(LastFirstKIndex - Integer.valueOf(Common.NumberLength), LastFirstKIndex);
}
else
{
//+200.34 GS -200.34 GS
int LastSymbol = Portdata.lastIndexOf(Common.symbol);
WeightTemp = Portdata.substring(LastSymbol, LastFirstKIndex);
}
PortList.add(WeightTemp);
Weight = GetStableWeight();
Portdata = ""; //取数成功后清空数据
}
}
}
break;
}
}
} catch (Exception e) {
System.err.println(e.toString());
logger.error("处理监控到的串口事件：" + e.getMessage(), e);
// 发生读取错误时显示错误信息后退出系统
}
break;
}
}
}
//获取稳定重量
private static String GetStableWeight()
{
String RunWeight = "";
//连续输出0时清空 PortList,防止内存溢出
int PortLength = PortList.size();
if(PortList.size()>10)
{
float OneNum = GetFloatNumber(PortList.get(PortLength - 11).toString());
float TenNum = GetFloatNumber(PortList.get(PortLength-1).toString());
//最后一个数减去倒数第十个数 变化小于1，表示数据稳定，然后取平均值 ，并清空PortList
if(Math.abs(TenNum - OneNum)<1)
{
float AllWeight = 0;
for(int i=0;i<10;i++)
{
AllWeight +=GetFloatNumber(PortList.get(PortLength - i-1).toString());
}
float WeightAvg = AllWeight/10.00f;
RunWeight = String.valueOf(GetFloatNumber(String.valueOf(WeightAvg)));
if(PortList.size()>100)
{
for(int i=0;i<50;i++)
{
PortList.remove(i);
}
}
}
}
return RunWeight;
}
//将字符串转为float
private static float GetFloatNumber(String fnum)
{
float ft = Float.valueOf(fnum);
int scale = 2;//设置位数
int roundingMode = 4;//表示四舍五入，可以选择其他舍值方式，例如去尾，等等.
BigDecimal bd = new BigDecimal((double)ft);
bd = bd.setScale(scale,roundingMode);
ft = bd.floatValue();
return ft;
}
//将ASCII转化为字符串
public static String asciiToString(String value)
{
StringBuffer sbu = new StringBuffer();
String[] chars = value.split(",");
for (int i = 0; i < chars.length; i++) {
sbu.append((char) Integer.parseInt(chars[i]));
}
return sbu.toString();
}