Question

起初我认为这是一个编程问题，因为我每10秒创建一次连接。哪些可能会创建连接并且没有正确关闭它。但是建议它不是编程而是实现/设计问题。

我需要每隔5或10秒检查一次可用的新资源，例如：testign.com/list_items。 webservices是使用cakephp开发的。

如果有任何可用资源，我将处理它。任何人都可以帮助/指导我连接到url并每10秒轮询一次新资源。

执行以下代码的每10秒会在20次循环之后拒绝连接或连接超时异常，并且在异常开始命中之后，该网址无法加载到浏览器中。

oracleIncoming = new URL("http://calvins.restasy.com/bills/list_current/Kitchen");
    inputStreamReaderList = new InputStreamReader(oracleIncoming.openStream());

    //= new InputStreamReader(oracle.openStream());
    for (int j = 0; j < 10;) {
        URLReader.inputStreamReaderList.close();
        inputStreamReaderList = new InputStreamReader(oracleIncoming.openStream());




        BufferedReader in = new BufferedReader(URLReader.inputStreamReaderList);

    String inputLine;
    while ((inputLine = in.readLine()) != null) {
        URLReader.storeInput = URLReader.storeInput + inputLine;
    }
    in.close();

        URLReader.storeInput = "";
        //send response with bill no
        if (URLReader.sendBillNo == true) {
            URLReader.sendBillNo = false;

            oracle = new URL("http://calvins.restasy.com/bills/successfully_generated/" +billNo+"/"+"Kitchen");
            inputStreamReader = new InputStreamReader(oracle.openStream());
             try {

                BufferedReader in2 = new BufferedReader(inputStreamReader);


                String inputLine2;
                while ((inputLine2 = in2.readLine()) != null) {
                    urlBillData2 = urlBillData2 + inputLine2;
                }
                in.close();
                inputStreamReader.close();
            } catch (Exception e) {
                System.out.println(e);
            }
            System.out.println("Successfully Printed Order " + billNo);
            //System.out.println("http://calvins.restasy.com/bills/successfully_generated/" +billNo);
        }
        Thread.sleep(10000);
    }
} catch (Exception e) {
    System.out.println(e);
    callWeb();
}

这是堆栈跟踪：

java.net.ConnectException: Connection timed out: connect
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:529)
at java.net.Socket.connect(Socket.java:478)
at sun.net.NetworkClient.doConnect(NetworkClient.java:163)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:394)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:529)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:233)
at sun.net.www.http.HttpClient.New(HttpClient.java:306)
at sun.net.www.http.HttpClient.New(HttpClient.java:323)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:970)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:911)
at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:836)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1172)
at java.net.URL.openStream(URL.java:1010)
at printerapp.URLReader.callWeb(URLReader.java:122)
at printerapp.URLReader.main(URLReader.java:71)

由于HotLicks建议仅在任何资源可用后才从Web服务响应，执行的php超时为30秒。如何使请求保持活动超过这个时间。增加PHP执行时间限制将是一个安全问题。

提前致谢。

Answer 1

while(true) {
    dataIncoming = new URL("http://xyz.com/bills/list_current/Kitchen");
    inputStreamReaderList = new InputStreamReader(dataIncoming.openStream());

    //Your code

    try {
        Thread.sleep(5000);
    } catch(Exception e) {
        //Thread.sleep() can throw an exception if you
        //notify the thread from another thread
    }
}

Answer 2

通常，您不应每5秒轮询一次网站。在需要接近即时响应的地方，网站应提供一种机制，您可以在其中发出获取，服务器将不会响应，直到有可用数据（尽管通常在几分钟后应该超时）。

我需要构建一个java应用程序，该应用程序每隔10秒就会在url上查询数据

2 个答案: