<CODE>package earth_survy;
import java.util.*;
import javax.microedition.io.*;
import java.io.*;
import com.sun.kjava.*;
import com.sun.cldc.io.palm.comm.*;
public class GetGpsData extends Spotlet {
static Graphics g=Graphics.getGraphics();
static Protocol serialPort = new Protocol();
static String url="0;baudrate=4800;bitsperchar=8;stopbits=1;parity=none";
static InputStream is;
// Open the serial Port for Gps Data Input
public boolean openPort(){
try {
serialPort.open(url,1, true);
is=serialPort.openInputStream();
return true;
}
catch (Exception ex) {
return false;
}
}
file://Close the serial Port
public boolean closePort(){
try {
is.close();
serialPort.close();
return true;
}
catch (Exception ex) {
return false;
}
}
file://Read the GPS data
file://Mark is "$GPRMC
file://rdLen is the buffer length
file://getlen is the return lenth;
public String readGpsData(String mark,int rdlen,int getlen){
byte[] readBuffer = new byte[rdlen];
String rawGpsData;
String Gprmc;
while (true){
try{
file://Read raw GPS data into a buffer;
is.read(readBuffer);
rawGpsData=new String(readBuffer);
file://determin the positon of the Mark==> $GPRMC;
int pos=rawGpsData.indexOf(mark);
if (pos>-1)
{
Gprmc=rawGpsData.substring(pos);
if (Gprmc.length()>getlen)
{
Gprmc=Gprmc.substring(0,getlen);
break;
}
}
}
catch(Exception e){
}
}
return Gprmc;
//end loop
}//end method
}</CODE>
参考文献
龚健雅.整体SIS的数据组织与处理方法.武汉：武汉测绘科技大学出版社，1993
http://www.palmheart.net/document/
C.Thomas Wu.An Introduction to Object-Oriented Programming with Java.2001
