为什么我的urlConnection.getContentLength大小始终为-1？

Question

可能重复：
getContentLength() returning -1 on some devices and not others为什么我的urlConnection.getContentLength大小始终为-1？

我针对Android应用程序，将显示从一个地方到另一个地方的路线。 所以首先我需要获取kml文件然后解析。但是，我的解析大小是-1，这不是假设的。解析大小必须大于-1，但我无法得到它。谁能帮我吗？谢谢！

// connect to map web service 
    StringBuilder urlString = new StringBuilder(); 
    urlString.append("http://maps.google.com/maps?f=d&hl=en"); 
    urlString.append("&saddr=");//from 
    urlString.append(Double.toString((double)src.getLatitudeE6()/1.0E6)); 
    urlString.append(","); 
    urlString.append(Double.toString((double)src.getLongitudeE6()/1.0E6)); 
    urlString.append("&daddr=");//to 
    urlString.append(Double.toString((double)dest.getLatitudeE6()/1.0E6)); 
    urlString.append(","); 
    urlString.append(Double.toString((double)dest.getLongitudeE6()/1.0E6)); 
    urlString.append("&ie=UTF8&0&om=0&output=kml"); 
    Log.d("DrawPath","URL="+urlString.toString()); 

    // get the kml (XML) doc. And parse it to get the coordinates(direction route). 
    Document doc = null; 
    HttpURLConnection urlConnection= null; 
    URL url = null; 

    try 
    { 
     url = new URL(urlString.toString()); 
     urlConnection=(HttpURLConnection)url.openConnection(); 
     urlConnection.setRequestMethod("GET"); 
     urlConnection.setDoOutput(true); 
     urlConnection.setDoInput(true); 
     urlConnection.connect(); 
     DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); 
     DocumentBuilder db = dbf.newDocumentBuilder(); 
     Log.d("Before parse", "size:" + urlConnection.getContentLength()); 
     doc = db.parse(urlConnection.getInputStream()); 

Answer 1

您需要为此传递正确的经度和纬度值。我可以用你的代码做到这一点。我试着将经度和纬度值修正为7位小数点。我试过this。

请尝试以下操作。 Pune => srcLat = 18.4577015; Pune => srcLong = 73.8552158;

孟买=> destLat = 19.017576; Mumbai => destLong = 72.8562427;

结果：解析大小前：47555