＆QUOT; java.lang.IllegalStateException：不能设置请求属性连接而成＆QUOT后;错误的Andr​​oid [英] "java.lang.IllegalStateException: Cannot set request property after connection is made" error in Android

问题描述

我是新来的Andr​​oid和试图获得一个网页的HTML内容，这是当我碰到这个问题。

I am new to Android and trying to get HTML content of a web page and that is when I came across this issue.

java.lang.IllegalStateException: Cannot set request property after connection is made

code：

public static String getHTMLPage(String inputURL, String host, String referer, String cookie, String breakString) {

    String htmlContent = "";
    try {
        URL u = new URL(inputURL);
        HttpURLConnection uc = (HttpURLConnection) u.openConnection();
        uc.setRequestProperty("Host", host);
        uc.setRequestProperty("Connection", "keep-alive");
        if (!referer.isEmpty()) {
            uc.setRequestProperty("Referer", referer);
        }
        uc.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/13.0.782.112 Safari/535.1");
        uc.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
        uc.setRequestProperty("Accept-Encoding", "html");
        uc.setRequestProperty("Accept-Language", "en-US,en;q=0.8");
        uc.setRequestProperty("Accept-Charset", "ISO-8859-1,utf-8;q=0.7,*;q=0.3");

        if (!cookie.isEmpty()) {
            uc.setRequestProperty("Cookie", cookie);
        }

        BufferedReader br = new BufferedReader(new InputStreamReader(uc.getInputStream()));
        String line = "";
        while ((line = br.readLine()) != null) {
            if (!breakString.isEmpty() && line.contains(breakString)) {
                break;
            }
            htmlContent += line;
        }
        br.close();
    } catch (Exception e) {
        System.out.println(e);
    }
    return htmlContent;
}

基本上，我已经在纯的Java 应用程序（它是工作的罚款），写了这个，我只是想再次使用相同的。我用Google搜索，发现几页的篇幅（<一个href=\"http://stackoverflow.com/questions/19565195/android-setrequestproperty-in-a-url-openconnection\">1,2,3,4),但他们没有涉及具体到 HttpURLConnection类直接（尽管这一问题，一些建议约了HTTPClient ，它被发现被德precated，我不想使用。）

Basically, I have written this in a pure java application (where it is working fine) and I just wanted to re-use the same. I have googled and found few SO pages (1,2,3,4), but none of them addresses the problem specific to HTTPURLConnection directly. (Though, some advised about HTTPClient, which is found to be deprecated which I don't want to use.)

添加 GETRESPONSE code（）的返回值200成功。

Adding getResponseCode() is returning the value as 200 successfully.

System.out.println("RESPONSE CODE : "+uc.getResponseCode());

我已经看过了<一个href=\"http://developer.android.com/reference/java/net/URLConnection.html#setRequestProperty(java.lang.String,%20java.lang.String)\"相对=nofollow>参考页，其中规定

公共无效调用setRequestProperty（String域，字符串newValue）以

设定指定的请求头字段的值。该值将
  仅由当前的URLConnection实例使用。这种方法可以
  在建立连接之前只能被称为

Sets the value of the specified request header field. The value will only be used by the current URLConnection instance. This method can only be called before the connection is established.

如何设置连接前请求属性？由于每code，我们只 HttpURLConnection类 HttpURLConnection类对象C $ C>）

How I can set the request property before making the connections ? As per the code, we are getting the HTTPURLConnection object only after opening connection for a specific URL (and casting it with HTTPURLConnection)

         HttpURLConnection uc = (HttpURLConnection) u.openConnection();

什么是正确的使用方法 HttpURLConnection类与调用setRequestProperty 陪读HTML页面？

What is the correct way to use HTTPURLConnection to read HTML page along with setRequestProperty ?

推荐答案

不被'URL.openConnection（）创建的连接。'当你输入或错误流或响应code已创建

The connection isn't created by 'URL.openConnection().` It is created when you get the input or error stream or the response code.

NB，你不应该叫 setDoOutput（真），除非你打算怎么办输出，你是不是在这里。它集HTTP方法POST。

NB you shouldn't call setDoOutput(true) unless you are going to do output, which you aren't here. It sets the HTTP method to POST.

这篇关于＆QUOT; java.lang.IllegalStateException：不能设置请求属性连接而成＆QUOT后;错误的Andr​​oid的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！