Android开发百度地图接入问题

Question

接入百度地图的SDK，按照他的定位文档定位为什么有200多米的偏差？

Answer 1

 /**
 * GPS坐标转换为百度地图坐标
 * 需要引入javabase64.jar 和json的一些包
 * 
 */
public class Gps2BaiDu
{
public static void main(String[] args)
{
//转换前的GPS坐标
double x=116.397428;
double y=39.90923;
//google 坐标转百度链接   //http://api.map.baidu.com/ag/coord/convert?from=2&to=4&x=116.32715863448607&y=39.990912172420714&callback=BMap.Convertor.cbk_3694
//gps坐标的type=0
//google坐标的type=2
//baidu坐标的type=4
String path = "http://api.map.baidu.com/ag/coord/convert?from=0&to=4&x="+x+"+&y="+y+"&callback=BMap.Convertor.cbk_7594";
try
{
//使用http请求获取转换结果
URL url = new URL(path);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5 * 1000);
InputStream inStream = conn.getInputStream();

ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while ((len = inStream.read(buffer)) != -1)
{
outStream.write(buffer, 0, len);
}
//得到返回的结果
String res = outStream.toString();
System.out.println(res);
            //处理结果
if (res.indexOf("(") > 0 && res.indexOf(")") > 0)
{
String str = res.substring(res.indexOf("(") + 1, res.indexOf(")"));
String err = res.substring(res.indexOf("error") + 7, res.indexOf("error") + 8);
if ("0".equals(err))
{
JSONObject js = JSONObject.fromObject(str);
//编码转换
String x1 = new String(Base64.decode(js.getString("x")));
String y1 = new String(Base64.decode(js.getString("y")));
System.out.println(x1 + "  " + y1);
}
}
} catch (Exception e)
{
e.printStackTrace();
}

}
}