java 测试IP

public static long calSpeed(String ip) {
        Runtime runtime = Runtime.getRuntime(); // 获取当前程序的运行进对象
        Process process = null; // 声明处理类对象
        String line = null; // 返回行信息
        InputStream is = null; // 输入流
        InputStreamReader isr = null; // 字节流
        BufferedReader br = null;
        try {
            process = runtime.exec("ping " + ip +" -w 1000"); // PING
            is = process.getInputStream(); // 实例化输入流
            isr = new InputStreamReader(is);// 把输入流转换成字节流
            br = new BufferedReader(isr);// 从字节中读取文本
            while ((line = br.readLine()) != null) {
                if (line.contains("TTL")) {
                    int begin = line.indexOf("TTL=");
                    String value = line.substring(begin+4,line.length());
                    return Integer.valueOf(value);
                }
            }
        } catch (IOException e) {
            System.out.println(e);
            runtime.exit(1);
        }finally{
            if(is!=null){
                try {
                    is.close();
                } catch (IOException e) {
                }
            }
            if(isr!=null){
                try {
                    isr.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            if(br!=null){
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return 10000;
    }