我想通过 HTTP post 从我的 Android 移动应用向服务器发送 XML 消息。
我按照以下步骤尝试使用 HttpUrlConnection:
URL url = new URL(vURL);
HttpUrlConnection conn = (HttpURLConnection) url.openConnection();
conn.setDoInput(true);
conn.setDoOutput(true);
// Adding headers (code removed)
conn.setRequestProperty("Content-Type", "text/xml; charset=utf-16");
OutputStream out = new BufferedOutputStream(conn.getOutputStream());
// Adding XML message to the connection output stream
// I have removed exception handling to improve readability for posting it here
out.write(pReq.getBytes()); // here pReq is the XML message in String
out.close();
conn.connect();
一旦我得到响应,流读取部分就以这种方式完成:
BufferedReader in = null;
StringBuffer sb;
String result = null;
try {
InputStreamReader isr = new InputStreamReader(is);
// Just in case, I've also tried:
// new InputStreamReader(is, "UTF-16");
// new InputStreamReader(is, "UTF-16LE");
// new InputStreamReader(is, "UTF-16BE");
// new InputStreamReader(is, "UTF-8");
in = new BufferedReader(isr);
sb = new StringBuffer("");
String line = "";
while ((line = in.readLine()) != null)
sb.append(line);
in.close();
result = sb.toString();
} catch (Exception e) {
e.printStackTrace();
}
现在我得到的结果字符串是某种不可读的格式/编码。
当我用 HttpClient 尝试同样的事情时,它工作正常。这是我在 HttpClient.execute 调用后获得 HttpResponse 后的流式阅读部分:
BufferedReader in = null;
InputStream is;
StringBuffer sb;
String decompbuff = null;
try {
is = pResponse.getEntity().getContent();
InputStreamReader isr = new InputStreamReader(is);
in = new BufferedReader(isr);
// Prepare the String buffer
sb = new StringBuffer("");
String line = "";
while ((line = in.readLine()) != null)
sb.append(line);
in.close();
// gZip decompression of response. Note: message was compressed before
// posting it via HttpClient (Posting code is not mentioned here)
decompbuff = Decompress(sb.toString());
} catch (Exception e) {
e.printStackTrace();
}
return decompbuff;
在理解问题方面提供一些帮助。
最佳答案
一个(严重的)问题可能是您忽略了输入和输出的编码。
输入
conn.setRequestProperty("Content-Type", "text/xml; charset=utf-16");
OutputStream out = new BufferedOutputStream(conn.getOutputStream());
// Adding XML message to the connection output stream
// I have removed exception handling to improve readability for posting it here
out.write(pReq.getBytes()); // <-- you use standard platform encoding
out.close();
更好:
out.write(pReq.getBytes("UTF-16"));
输出
你可能忽略了压缩,它看起来像这样更好(取自 DavidWebb ):
static InputStream wrapStream(String contentEncoding, InputStream inputStream)
throws IOException {
if (contentEncoding == null || "identity".equalsIgnoreCase(contentEncoding)) {
return inputStream;
}
if ("gzip".equalsIgnoreCase(contentEncoding)) {
return new GZIPInputStream(inputStream);
}
if ("deflate".equalsIgnoreCase(contentEncoding)) {
return new InflaterInputStream(inputStream, new Inflater(false), 512);
}
throw new RuntimeException("unsupported content-encoding: " + contentEncoding);
}
// ...
InputStream is = wrapStream(conn.getContentEncoding(), is);
InputStreamReader isr = new InputStreamReader(is, "UTF-16");
in = new BufferedReader(isr);
sb = new StringBuffer("");
String line = "";
while ((line = in.readLine()) != null)
sb.append(line); // <-- you're swallowing linefeeds!
in.close();
result = sb.toString();
最好让 XML-Parser 直接使用您的 InputStream。不要创建 JAVA 字符串,而是让解析器扫描字节。它会自动检测 XML 的编码。
一般来说还是会有问题,因为我们不知道你使用的是什么类型的UTF-16。可以是 BigEndian 或 LittleEndian。这就是为什么我问,如果你真的需要 UTF-16。如果您不必处理某些亚洲语言,UTF-8 应该更高效且更易于使用。
所以我给你的“解决方案”不能保证有效 - 你必须稍微摆弄一下 UTF-16 BE/LE,祝你好运和耐心。
另一点说明:在上面的示例中,您首先构建了 String,然后对其进行了解压缩
。那是错误的顺序。流是压缩的(gzip、deflate),必须先解压。然后你得到字符串。
关于android - Android 中 HttpUrlConnection 的编码问题,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/21876227/