Question

例如，我有一个GPS记录器输出GPGGA字符串 $GPGGA,1714.0,3723.465874,N,12202.26954,W,2,6,1.2,18.893,M,-25.669,M,2.0,0031*4F

该字符串以逗号分隔。在Java中工作，我试图提取位置信息。有人可以帮助我使用所需的正则表达式语句

3723.465874在第2个和第3个逗号之间
N在第3个和第4个逗号之间
12202.26954在第4个和第5个逗号之间
W在第5个和第6个逗号之间

或者，或许只是一个例子，所以我可以推断其他人。

谢谢。

Answer 1

只需在逗号上拆分字符串，然后从结果字符串数组中获取相应的部分。

String gpgga = 
   "$GPGGA,1714.0,3723.465874,N,12202.26954,W,2,6,1.2,18.893,M,-25.669,M,2.0,0031*4F"
String[] parts = gpgga.split(",");
String latitude = parts[2];
String nb = parts[3];
String longitude = parts[4];
String ew = parts[5];

Answer 2

由于您有一个干净的分隔符，您可以使用String.split，如下所示：

String data = "$GPGGA,1714.0,3723.465874,N,12202.26954,W,2,6,1.2,18.893,M,-25.669,M,2.0,0031*4F";
String[] parts = data.split(",");
String p2 = parts[2]; // 3723.465874
String p3 = parts[3]; // N
String p4 = parts[4]; // 12202.26954
String p5 = parts[5]; // W

Demo on ideone.

Answer 3

来自this gist：

package es.agroguia.model;

import java.util.HashMap;
import java.util.Map;


public class NMEA {

    class GPSPosition {
        public float time = 0.0f;
        public float lat = 0.0f;
        public float lon = 0.0f;
        public boolean fixed = false;
        public int quality = 0;
        public float dir = 0.0f;
        public float altitude = 0.0f;
        public float velocity = 0.0f;

        public void updatefix() {
            fixed = quality > 0;
        }

        public String toString() {
            return String.format("POSITION: lat: %f, lon: %f, time: %f, Q: %d, dir: %f, alt: %f, vel: %f", lat, lon, time, quality, dir, altitude, velocity);
        }
    }

    GPSPosition position = new GPSPosition();

    private static final Map<String, SentenceParser> sentenceParsers = new HashMap<String, SentenceParser>();

    public NMEA() {
        sentenceParsers.put("GPGGA", new GPGGA());
        sentenceParsers.put("GPGGL", new GPGGL());
        sentenceParsers.put("GPRMC", new GPRMC());
        sentenceParsers.put("GPRMZ", new GPRMZ());
        //only really good GPS devices have this sentence but ...
        sentenceParsers.put("GPVTG", new GPVTG());
    }

    public GPSPosition parse(String line) {

        if(line.startsWith("$")) {
            String nmea = line.substring(1);
            String[] tokens = nmea.split(",");
            String type = tokens[0];
            //TODO check crc
            if(sentenceParsers.containsKey(type)) {
                sentenceParsers.get(type).parse(tokens, position);
            }
            position.updatefix();
        }

        return position;
    }
}
interface SentenceParser {
        public boolean parse(String [] tokens, GPSPosition position);
}

    // utils
    static float Latitude2Decimal(String lat, String NS) {
        float med = Float.parseFloat(lat.substring(2))/60.0f;
        med +=  Float.parseFloat(lat.substring(0, 2));
        if(NS.startsWith("S")) {
            med = -med;
        }
        return med;
    }

    static float Longitude2Decimal(String lon, String WE) {
        float med = Float.parseFloat(lon.substring(3))/60.0f;
        med +=  Float.parseFloat(lon.substring(0, 3));
        if(WE.startsWith("W")) {
            med = -med;
        }
        return med;
    }

    // parsers 
    class GPGGA implements SentenceParser {
        public boolean parse(String [] tokens, GPSPosition position) {
            position.time = Float.parseFloat(tokens[1]);
            position.lat = Latitude2Decimal(tokens[2], tokens[3]);
            position.lon = Longitude2Decimal(tokens[4], tokens[5]);
            position.quality = Integer.parseInt(tokens[6]);
            position.altitude = Float.parseFloat(tokens[9]);
            return true;
        }
    }
 }

Answer 4

    String input = "$GPGGA,1714.0,3723.465874,N,12202.26954,W,2,6,1.2,18.893,M,-25.669,M,2.0,0031*4F";
    Pattern pattern = Pattern.compile("^\\$GPGGA,[\\d\\.]*,([\\d\\.]+),([NS]),([\\d\\.]+),([EW]),.*");
    Matcher matcher = pattern.matcher(input);
    if (matcher.matches()) {
        for(int i=0; i <= matcher.groupCount(); i++) {
            System.out.println("Group " + i + " = " + matcher.group(i));
        }
    } else {
        throw new IllegalArgumentException("Invalid input!");
    }

输出：

Group 0 = $GPGGA,1714.0,3723.465874,N,12202.26954,W,2,6,1.2,18.893,M,-25.669,M,2.0,0031*4F
Group 1 = 3723.465874
Group 2 = N
Group 3 = 12202.26954
Group 4 = W

正则表达式从GPGGA字符串中提取纬度和长度

4 个答案: