java中怎么调用百度地图api?

在百度开发者网站里申请账号，调用api接口

public Map<String, BigDecimal> getLatAndLngByAddress(String addr){
        String address = "";
        String lat = "";
        String lng = "";
        try {  
            address = java.net.URLEncoder.encode(addr,"UTF-8");  
        } catch (UnsupportedEncodingException e1) {  
            e1.printStackTrace();  
        } 
        String url = String.format("http://api.map.baidu.com/geocoder/v2/?"
        +"ak=4rcKAZKG9OIl0wDkICSLx8BA&output=json&address=%s",address);
        URL myURL = null;
        URLConnection httpsConn = null;  
        //进行转码
        try {
            myURL = new URL(url);
        } catch (MalformedURLException e) {

        }
        try {
            httpsConn = (URLConnection) myURL.openConnection();
            if (httpsConn != null) {
                InputStreamReader insr = new InputStreamReader(
                        httpsConn.getInputStream(), "UTF-8");
                BufferedReader br = new BufferedReader(insr);
                String data = null;
                if ((data = br.readLine()) != null) {
                    lat = data.substring(data.indexOf("\"lat\":") 
                    + ("\"lat\":").length(), data.indexOf("},\"precise\""));
                    lng = data.substring(data.indexOf("\"lng\":") 
                    + ("\"lng\":").length(), data.indexOf(",\"lat\""));
                }
                insr.close();
            }
        } catch (IOException e) {

        }
        Map<String, BigDecimal> map = new HashMap<String, BigDecimal>();
        map.put("lat", new BigDecimal(lat));
        map.put("lng", new BigDecimal(lng));
        return map;
}

获取经度纬度？？

你想调用百度API，首先保证网络能链接到那，然后再去百度开发者平台

http://app.baidu.com/ 申请个账号 ，再然后借鉴上面那哥们的代码 ，具体实现你想要实现的功能