在我的代码中,我使用一些Http Get请求来将一些文件作为流来下载.我使用以下代码：
public String getClassName(String url) throws ClientProtocolException,IOException {
HttpResponse response = sendGetRequestJsonText(url);
Header[] all = response.getAllHeaders();
for (Header h : all) {
System.out.println(h.getName() + ": " + h.getValue());
}
Header[] headers = response.getHeaders("Content-disposition");
InputStreamParser.convertStreamToString(response.getEntity().getContent());
String result = "";
for (Header header : headers) {
result = header.getValue();
}
return result.substring(result.indexOf("''") + "''".length(),result.length()).trim();
}
但是这会下载响应的全部内容.我想仅检索没有内容的HTTP标头. HEAD请求似乎不起作用,因为我得到状态501,没有实现.我怎样才能做到这一点？
解决方法
您可以考虑仅提出一个
HEAD请求,而不是发出GET请求：
The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response. The Metainformation contained in the HTTP headers in response to a HEAD request SHOULD be identical to the information sent in response to a GET request. This method can be used for obtaining Metainformation about the entity implied by the request without transferring the entity-body itself. This method is often used for testing hypertext links for validity,accessibility,and recent modification.