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package tim.prune.load;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import tim.prune.App;
import tim.prune.data.Field;
import tim.prune.data.SourceInfo;
/**
* Class to handle the loading of Nmea files
*/
public class NmeaFileLoader
{
/** App for callback of file loading */
private App _app = null;
/**
* Constructor
* @param inApp App object
*/
public NmeaFileLoader(App inApp)
{
_app = inApp;
}
/**
* Open the selected file
* @param inFile File to open
*/
public void openFile(File inFile)
{
BufferedReader reader = null;
ArrayList<NmeaMessage> messages = new ArrayList<NmeaMessage>();
String lastDate = null;
try
{
reader = new BufferedReader(new FileReader(inFile));
String currLine = reader.readLine();
boolean newSegment = true;
while (currLine != null)
{
// Try to make an NmeaMessage object for each line of file
if (currLine.trim().length() > 0)
{
NmeaMessage message = processGGA(currLine);
if (message != null)
{
if (message.hasFix())
{
message.setSegment(newSegment);
message.setDate(lastDate);
// add message to list
messages.add(message);
}
// Start a new segment if fix lost
newSegment = !message.hasFix();
}
else {
String date = getDateFromRMC(currLine);
if (date != null)
{
if (lastDate == null && !messages.isEmpty()) {
// Backfill first few messages received before the first date
for (int m=0; m<messages.size(); m++) {
messages.get(m).setDate(date);
}
}
lastDate = date;
}
}
}
// Read next line, if any
currLine = reader.readLine();
}
}
catch (IOException ioe) {
_app.showErrorMessage("error.load.dialogtitle", "error.load.noread");
}
finally
{
// close file ignoring errors
try {
if (reader != null) reader.close();
}
catch (Exception e) {}
}
if (messages.size() > 0)
{
_app.informDataLoaded(getFieldArray(), makeDataArray(messages),
null, new SourceInfo(inFile, SourceInfo.FILE_TYPE.NMEA), null);
}
}
/**
* Process the given GGA sentence and return the message
* @param inLine line to process
* @return message object
*/
private static NmeaMessage processGGA(String inLine)
{
// Only consider lines which are long enough and begin with the GPS position sentence
if (inLine == null || inLine.length() < 20 || !inLine.startsWith("$GPGGA")) {
return null;
}
// Assume comma delimiter, split into array
String[] splitLine = inLine.split(",");
if (splitLine != null && splitLine.length >= 10)
{
return new NmeaMessage(splitLine[2] + splitLine[3], // latitude
splitLine[4] + splitLine[5], // longitude
splitLine[9], // altitude
splitLine[1], // timestamp
splitLine[6]); // fix
}
// Couldn't parse it, return null
return null;
}
/**
* Process the given MRC sentence and return the date
* @param inLine line to process
* @return date, if any
*/
private static String getDateFromRMC(String inLine)
{
// Only consider lines which are long enough and begin with the RMC sentence
if (inLine == null || inLine.length() < 20 || !inLine.startsWith("$GPRMC")) {
return null;
}
// Assume comma delimiter, split into array
String[] splitLine = inLine.split(",");
if (splitLine != null && splitLine.length >= 10)
{
return splitLine[9]; // date in position 9
}
// Couldn't parse it, return null
return null;
}
/**
* Make an object array from the data list
* @param inList list of messages
* @return object array for loading
*/
private static Object[][] makeDataArray(ArrayList<NmeaMessage> inList)
{
Object[][] result = new Object[inList.size()][];
for (int i=0; i<inList.size(); i++) {
result[i] = inList.get(i).getStrings();
}
return result;
}
/**
* @see tim.prune.load.xml.XmlHandler#getFieldArray()
*/
public Field[] getFieldArray()
{
final Field[] fields = {Field.LATITUDE, Field.LONGITUDE, Field.ALTITUDE,
Field.TIMESTAMP, Field.NEW_SEGMENT};
return fields;
}
}
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