java定时发送http请求

public class HttpRequest {    /**     * 向指定URL发送GET方法的请求     *      * @param url     *            发送请求的URL     * @param param     *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。     * @return URL 所代表远程资源的响应结果     */    public static String sendGet(String url, String param) {        String result = "";        BufferedReader in = null;        try {            String urlNameString = url + "?" + param;            URL realUrl = new URL(urlNameString);            // 打开和URL之间的连接            URLConnection connection = realUrl.openConnection();            // 设置通用的请求属性            connection.setRequestProperty("accept", "*/*");            connection.setRequestProperty("connection", "Keep-Alive");            connection.setRequestProperty("user-agent",                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");            // 建立实际的连接            connection.connect();            // 获取所有响应头字段            Map<String, List<String>> map = connection.getHeaderFields();            // 遍历所有的响应头字段            for (String key : map.keySet()) {                System.out.println(key + "--->" + map.get(key));            }            // 定义 BufferedReader输入流来读取URL的响应            in = new BufferedReader(new InputStreamReader(                    connection.getInputStream()));            String line;            while ((line = in.readLine()) != null) {                result += line;            }        } catch (Exception e) {            System.out.println("发送GET请求出现异常！" + e);            e.printStackTrace();        }        // 使用finally块来关闭输入流        finally {            try {                if (in != null) {                    in.close();                }            } catch (Exception e2) {                e2.printStackTrace();            }        }        return result;    }    /**     * 向指定 URL 发送POST方法的请求     *      * @param url     *            发送请求的 URL     * @param param     *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。     * @return 所代表远程资源的响应结果     */    public static String sendPost(String url, String param) {        PrintWriter out = null;        BufferedReader in = null;        String result = "";        try {            URL realUrl = new URL(url);            // 打开和URL之间的连接            URLConnection conn = realUrl.openConnection();            // 设置通用的请求属性            conn.setRequestProperty("accept", "*/*");            conn.setRequestProperty("connection", "Keep-Alive");            conn.setRequestProperty("user-agent",                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");            // 发送POST请求必须设置如下两行            conn.setDoOutput(true);            conn.setDoInput(true);            // 获取URLConnection对象对应的输出流            out = new PrintWriter(conn.getOutputStream());            // 发送请求参数            out.print(param);            // flush输出流的缓冲            out.flush();            // 定义BufferedReader输入流来读取URL的响应            in = new BufferedReader(                    new InputStreamReader(conn.getInputStream()));            String line;            while ((line = in.readLine()) != null) {                result += line;            }        } catch (Exception e) {            System.out.println("发送 POST 请求出现异常！"+e);            e.printStackTrace();        }        //使用finally块来关闭输出流、输入流        finally{            try{                if(out!=null){                    out.close();                }                if(in!=null){                    in.close();                }            }            catch(IOException ex){                ex.printStackTrace();            }        }        return result;    }    }

import java.text.SimpleDateFormat;import java.util.Calendar;import java.util.TimerTask;public class MyTask extends TimerTask{    private int i= 0;    @Override    public void run() {        Calendar c= Calendar.getInstance();        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//      System.out.println("当前时间："+sdf.format(c.getTime()));        if(c.get(Calendar.DAY_OF_MONTH)==1){            i++;            System.out.println("当前时间："+sdf.format(c.getTime()));            System.out.println("第"+i+"次执行任务开始");            String s=HttpRequest.sendGet("http://localhost:8080/taizhoushopping/test1", "key=555&v=456");            System.out.println("应答信息："+s);            System.out.println("第"+i+"次执行任务结束");        }    }}

public class Run {    public static void main(String[] args) {//        //发送 GET 请求//        String s=HttpRequest.sendGet("http://localhost:8080/taizhoushopping/test1", "key=555&v=456");//        System.out.println(s);        //发送 POST 请求//        String sr=HttpRequest.sendPost("http://localhost:8080/taizhoushopping/test1", "key=123&v=456");//        System.out.println(sr);        Run r = new Run();        r.runtask();    }    public void runtask(){        Calendar c1 = Calendar.getInstance();        c1.setTime(new Date());        Timer t = new Timer();        Calendar c2 = Calendar.getInstance();        c2.set(Calendar.DAY_OF_MONTH, c1.get(Calendar.DAY_OF_MONTH)+1);        c2.set(Calendar.HOUR_OF_DAY, 0);        c2.set(Calendar.SECOND, 0);        c2.set(Calendar.MINUTE, 0);        long diffs = c2.getTimeInMillis()-c1.getTimeInMillis();        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");        MyTask task = new MyTask();        t.scheduleAtFixedRate(task, diffs, 24*60*60*1000);    }}

任务执行：从启动计时，第二天凌晨第一次执行任务，之后每隔24小时执行一次，若当天时间为每月1号，则发送http请求