Question

我想从一个独立的Java类调用一个JSP页面（例如：http://www.google.jsp）。我不想使用servlet。 HttpURLConnection似乎不起作用。它没有带我到JSP页面。当我使用下面的代码来调用JSP时，我的JSP中的print语句没有被调用，但是如果我单独调用JSP URL，则print语句可用。尝试搜索但没有明确答案。

我使用HttpURLConnection的代码片段如下：

URL obj = new URL(url);
HttpURLConnection conn = (HttpURLConnection) obj.openConnection();
conn.setReadTimeout(5000);
conn.addRequestProperty("Accept-Language", "en-US,en;q=0.8");
conn.addRequestProperty("User-Agent", "Mozilla");
conn.addRequestProperty("Referer", "google.com");
System.out.println("Request URL ... " + url);
boolean redirect = false;
// normally, 3xx is redirect
int status = conn.getResponseCode();
if (status != HttpURLConnection.HTTP_OK) {
    if (status == HttpURLConnection.HTTP_MOVED_TEMP
        || status == HttpURLConnection.HTTP_MOVED_PERM
            || status == HttpURLConnection.HTTP_SEE_OTHER)
    redirect = true;
}
conn.setInstanceFollowRedirects(true);
System.out.println("Response Code ... " + status);
System.out.println("Response Message ... " + conn.getResponseMessage());
if (redirect) {
    // get redirect url from "location" header field
    String newUrl = conn.getHeaderField("Location");
    // get the cookie if need, for login
    String cookies = conn.getHeaderField("Set-Cookie");
    // open the new connnection again
    conn = (HttpURLConnection) new URL(newUrl).openConnection();
    conn.setRequestProperty("Cookie", cookies);
    conn.addRequestProperty("Accept-Language", "en-US,en;q=0.8");
    conn.addRequestProperty("User-Agent", "Mozilla");
    conn.addRequestProperty("Referer", "google.com");
    System.out.println("Redirect to URL : " + newUrl);
}
BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String inputLine;
StringBuffer html = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
    html.append(inputLine);
}
in.close();
System.out.println("Done")

输出：

sResultsURL....http://www.google.jsp
Request URL ... http://www.google.jsp
Response Code ... 200
Response Message ... OK
Done

Answer 1

我已经执行了您的代码，但它确实有效。请注意，我只是改变了

<PARAM ATT1='DESPIECE' 
       ATT2='BU_O_DES' 
       ATT3= '1' 
       ATT3= '0' 
       ATT4='1.0' 
       ATT4= 'BU.SD01.L02' 
       ATT5= 'BU.SD01.L02' 
       ATT6='1ESP1586CV00' 
       ATT7='CLASS FIFO AÑOJO < 350'
       ATT8='08/06/2016' 
       ATT9='115001' 
       MARCA_EMPRESA='false' 
       VARIANTE='' 
       ID_CLASS_ESTABILIZACION='91'
 />

到

HttpURLConnection conn = (HttpURLConnection) obj.openConnection();

这是我jsp的唯一代码：

HttpURLConnection conn = (HttpURLConnection) url.openConnection();

此外，将此添加到您的java类，您可以记录jsp的内容以确保您调用正确的URL：

<% System.out.println("writing"); %>

从独立的Java类调用JSP页面（不使用Servlet）

1 个答案: