public static void printCallStatck() {

        Throwable ex = new Throwable();

        StackTraceElement[] stackElements = ex.getStackTrace();

        if (stackElements != null) {

            Log.e("Chw","printCallStatck+++++++++++++++++++++++");

            for (int i = 0; i < stackElements.length; i++) {

                Log.e("Chw",stackElements[i].getClassName()+"."+stackElements[i].getMethodName()+"-"+stackElements[i].getLineNumber());

            }

            Log.e("Chw","printCallStatck----end+++++++++++++++++++++++");

        }

    }

判断是否连接互联网

/**

 *  判断是否有外网连接（普通方法不能判断外网的网络是否连接，比如连接上局域网）

 * @return

 */

public static boolean ping(){

    boolean result=false;

    try {

        String ip ="www.baidu.com";// ping 的地址，可以换成任何一种可靠的外网

        Process process=Runtime.getRuntime().exec("ping -c 2 -w 100 "+ip);//ping 网址3次

        int status= process.waitFor();

        if(status==0){

            result= true;

        }

    } catch (IOException e) {

        e.printStackTrace();

    } catch (InterruptedException e) {

        e.printStackTrace();

    }

    Log.e("Chw","ping  result "+result);

    return result;

}