java 串口编程----设置缓冲屈来读取串口数据
http://blog.sina.com.cn/s/blog_667528fd0100yuvl.html
package test;
import java.io.InputStream;
import java.io.OutputStream;
import javax.comm.CommPortIdentifier;
import javax.comm.SerialPort;
//串口操作主类
public class SerialBean {
static String portName;
CommPortIdentifier portId;
SerialPort serialPort;
static InputStream in;
static OutputStream out;
SerialBuffer sb;
ReadSeriral rt;
public SerialBean(int portId){
portName="COM"+String.valueOf(portId);
}
public int Initialize(){
int initsuccess=1;
int initfail=-1;
try {
portId=CommPortIdentifier.getPortIdentifier(portName);
try {
serialPort=(SerialPort)portId.open("serial_communication",2000);
in=serialPort.getInputStream();
out=serialPort.getOutputStream();
serialPort.setSerialPortParams(9600,SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);
} catch (Exception e) {
System.out.println("初始化串口失败！");
return initfail;
}
sb=new SerialBuffer();
rt=new ReadSeriral(sb,in);
rt.start();
return initsuccess;
} catch (Exception e) {
System.out.print("初始化串口失败!");
return initfail;
}
}
public String ReadPort(int length){
String msg="";
msg=sb.getMsg(length);
return msg;
}
public void WritePort(String msg){
try {
for(int i=0;i<msg.length();i++){
out.write(msg.charAt(i));
}
} catch (Exception e) {
e.printStackTrace();
}
}
public void ClosePort(){
try {
rt.stop();
serialPort.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public String getPortName(){
return portName;
}
public static void main(String[] args) {
SerialBean sb=new SerialBean(1);
String msg;
sb.Initialize();
System.out.println("串口"+sb.getPortName()+"初始化成功！");
for (int i = 5; i <= 10; i++) {
msg=sb.ReadPort(i);
sb.WritePort("reply:"+msg);
}
sb.ClosePort();
}
}
=============================================================================
package test;
public class SerialBuffer {
private String contentString="";
private String currentMsg,tempContent;
private boolean available=false;
private int lengthNeeded=1;
public synchronized String getMsg(int length) {
lengthNeeded=length;
notifyAll();
if(lengthNeeded>contentString.length()){
available=false;
while(available==false){
try {
wait();
} catch (Exception e) {
e.printStackTrace();
}
}
}
currentMsg=contentString.substring(0,lengthNeeded);
tempContent=contentString.substring(lengthNeeded);
contentString=tempContent;
lengthNeeded=1;
notifyAll();
return currentMsg;
}
public synchronized void putChar(int c) {
Character d=new Character((char)c);
contentString=contentString.concat(d.toString());
if(lengthNeeded<contentString.length()){
available=true;
}
notifyAll();
}
}
===================================================================
package test;
import java.io.InputStream;
public class ReadSeriral extends Thread{
private SerialBuffer commBuffer;
private InputStream commPort;
public ReadSeriral(SerialBuffer sb,InputStream port){
commBuffer=sb;
commPort=port;
}
public void run(){
int c;
try {
while(true){
c=commPort.read();
commBuffer.putChar(c);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}