userposrequester.java

主要用于基站定位的java实现

/*
 * UserPosRequester.java
 */
package com.sonyericsson.example;

import javax.microedition.lcdui.TextField;
import javax.microedition.location.Coordinates;
import javax.microedition.location.Criteria;
import javax.microedition.location.Location;
import javax.microedition.location.LocationException;
import javax.microedition.location.LocationProvider;

/**
 *
 */
public class UserPosRequester {

  TextField t1;
  LocationProvider lp = null;
  private long requestStart = 0;
  private long timeToFirstFix = 0;

  /** Creates a new instance of UserPosRequester */
  public UserPosRequester(TextField textField) {
    t1 = textField;
    t1.setMaxSize(80);
    
  }

  void init() {
    t1.setString("Press ok to initiate a location request");
    
    try {
      lp = LocationProvider.getInstance(null);
    } catch (LocationException l) {
      l.printStackTrace();
    }
  }

  public void requestPos() {
    Location loc = null;

    try {
      requestStart = System.currentTimeMillis();
      loc = lp.getLocation(180);
      timeToFirstFix = (System.currentTimeMillis() - requestStart);
    } catch (InterruptedException i) {
      i.printStackTrace();
    } catch (LocationException r) {
      r.printStackTrace();
    }

    if (loc != null && loc.isValid()) {
      String lon = Coordinates.convert(loc.getQualifiedCoordinates().getLongitude(), Coordinates.DD_MM_SS);
      String lat = Coordinates.convert(loc.getQualifiedCoordinates().getLatitude(), Coordinates.DD_MM_SS);

      String str = lon + " : " + lat + "\nTimeToFirstFix:\n " + timeToFirstFix + "ms";
      System.out.println("str: " + str);
      t1.setString(str);
    } else {
      t1.setString("Invalid pos returned");
    }
  }
}