Answers:
由于原始答案中的某些类在Apache HTTP Components的较新版本中已弃用,因此,我将发布此更新。
顺便说一句,您可以在此处访问完整的文档以获取更多示例。
HttpClient httpclient = HttpClients.createDefault();
HttpPost httppost = new HttpPost("http://www.a-domain.com/foo/");
// Request parameters and other properties.
List<NameValuePair> params = new ArrayList<NameValuePair>(2);
params.add(new BasicNameValuePair("param-1", "12345"));
params.add(new BasicNameValuePair("param-2", "Hello!"));
httppost.setEntity(new UrlEncodedFormEntity(params, "UTF-8"));
//Execute and get the response.
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
if (entity != null) {
try (InputStream instream = entity.getContent()) {
// do something useful
}
}
我建议使用Apache HttpClient。它更快,更容易实现。
HttpPost post = new HttpPost("http://jakarata.apache.org/");
NameValuePair[] data = {
new NameValuePair("user", "joe"),
new NameValuePair("password", "bloggs")
};
post.setRequestBody(data);
// execute method and handle any error responses.
...
InputStream in = post.getResponseBodyAsStream();
// handle response.
有关更多信息,请检查以下URL:http : //hc.apache.org/
在原始Java中,发送POST请求很容易。以a开头URL
,我们不需要将其转换为URLConnection
using url.openConnection();
。之后,我们需要将其强制转换为HttpURLConnection
,以便我们可以访问其setRequestMethod()
方法来设置方法。最后,我们说我们将通过连接发送数据。
URL url = new URL("https://www.example.com/login");
URLConnection con = url.openConnection();
HttpURLConnection http = (HttpURLConnection)con;
http.setRequestMethod("POST"); // PUT is another valid option
http.setDoOutput(true);
然后,我们需要声明要发送的内容:
来自http表单的普通POST具有定义明确的格式。我们需要将输入转换为以下格式:
Map<String,String> arguments = new HashMap<>();
arguments.put("username", "root");
arguments.put("password", "sjh76HSn!"); // This is a fake password obviously
StringJoiner sj = new StringJoiner("&");
for(Map.Entry<String,String> entry : arguments.entrySet())
sj.add(URLEncoder.encode(entry.getKey(), "UTF-8") + "="
+ URLEncoder.encode(entry.getValue(), "UTF-8"));
byte[] out = sj.toString().getBytes(StandardCharsets.UTF_8);
int length = out.length;
然后,我们可以使用适当的标头将表单内容附加到http请求并将其发送。
http.setFixedLengthStreamingMode(length);
http.setRequestProperty("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
http.connect();
try(OutputStream os = http.getOutputStream()) {
os.write(out);
}
// Do something with http.getInputStream()
我们也可以使用java发送json,这也很容易:
byte[] out = "{\"username\":\"root\",\"password\":\"password\"}" .getBytes(StandardCharsets.UTF_8);
int length = out.length;
http.setFixedLengthStreamingMode(length);
http.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
http.connect();
try(OutputStream os = http.getOutputStream()) {
os.write(out);
}
// Do something with http.getInputStream()
请记住,不同的服务器接受json的不同内容类型,请参阅此问题。
由于格式更加复杂,发送文件被认为更具挑战性。我们也将增加对以字符串形式发送文件的支持,因为我们不想将文件完全缓冲到内存中。
为此,我们定义了一些辅助方法:
private void sendFile(OutputStream out, String name, InputStream in, String fileName) {
String o = "Content-Disposition: form-data; name=\"" + URLEncoder.encode(name,"UTF-8")
+ "\"; filename=\"" + URLEncoder.encode(filename,"UTF-8") + "\"\r\n\r\n";
out.write(o.getBytes(StandardCharsets.UTF_8));
byte[] buffer = new byte[2048];
for (int n = 0; n >= 0; n = in.read(buffer))
out.write(buffer, 0, n);
out.write("\r\n".getBytes(StandardCharsets.UTF_8));
}
private void sendField(OutputStream out, String name, String field) {
String o = "Content-Disposition: form-data; name=\""
+ URLEncoder.encode(name,"UTF-8") + "\"\r\n\r\n";
out.write(o.getBytes(StandardCharsets.UTF_8));
out.write(URLEncoder.encode(field,"UTF-8").getBytes(StandardCharsets.UTF_8));
out.write("\r\n".getBytes(StandardCharsets.UTF_8));
}
然后,我们可以使用这些方法来创建多部分的发布请求,如下所示:
String boundary = UUID.randomUUID().toString();
byte[] boundaryBytes =
("--" + boundary + "\r\n").getBytes(StandardCharsets.UTF_8);
byte[] finishBoundaryBytes =
("--" + boundary + "--").getBytes(StandardCharsets.UTF_8);
http.setRequestProperty("Content-Type",
"multipart/form-data; charset=UTF-8; boundary=" + boundary);
// Enable streaming mode with default settings
http.setChunkedStreamingMode(0);
// Send our fields:
try(OutputStream out = http.getOutputStream()) {
// Send our header (thx Algoman)
out.write(boundaryBytes);
// Send our first field
sendField(out, "username", "root");
// Send a seperator
out.write(boundaryBytes);
// Send our second field
sendField(out, "password", "toor");
// Send another seperator
out.write(boundaryBytes);
// Send our file
try(InputStream file = new FileInputStream("test.txt")) {
sendFile(out, "identification", file, "text.txt");
}
// Finish the request
out.write(finishBoundaryBytes);
}
// Do something with http.getInputStream()
out.write(finishBoundaryBytes);
需要线路?http.connect();
将执行发送POST,不是吗?
requests.post('http://httpbin.org/post', data = {'key':'value'})
的Python语言相比……我是Java的新手,所以对我来说,“易”一词的用法非常奇怪:)
String rawData = "id=10";
String type = "application/x-www-form-urlencoded";
String encodedData = URLEncoder.encode( rawData, "UTF-8" );
URL u = new URL("http://www.example.com/page.php");
HttpURLConnection conn = (HttpURLConnection) u.openConnection();
conn.setDoOutput(true);
conn.setRequestMethod("POST");
conn.setRequestProperty( "Content-Type", type );
conn.setRequestProperty( "Content-Length", String.valueOf(encodedData.length()));
OutputStream os = conn.getOutputStream();
os.write(encodedData.getBytes());
encode(String)
不推荐使用。您必须使用encode(String, String)
,它指定编码类型。范例:encode(rawData, "UTF-8")
。
第一个答案很好,但是我必须添加try / catch以避免Java编译器错误。
另外,我很难弄清楚如何HttpResponse
使用Java库阅读。
这是更完整的代码:
/*
* Create the POST request
*/
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost("http://example.com/");
// Request parameters and other properties.
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("user", "Bob"));
try {
httpPost.setEntity(new UrlEncodedFormEntity(params, "UTF-8"));
} catch (UnsupportedEncodingException e) {
// writing error to Log
e.printStackTrace();
}
/*
* Execute the HTTP Request
*/
try {
HttpResponse response = httpClient.execute(httpPost);
HttpEntity respEntity = response.getEntity();
if (respEntity != null) {
// EntityUtils to get the response content
String content = EntityUtils.toString(respEntity);
}
} catch (ClientProtocolException e) {
// writing exception to log
e.printStackTrace();
} catch (IOException e) {
// writing exception to log
e.printStackTrace();
}
e.printStackTrace()
无法处理任何事情。
使用Apache HTTP组件的一种简单方法是
Request.Post("http://www.example.com/page.php")
.bodyForm(Form.form().add("id", "10").build())
.execute()
.returnContent();
通过发布请求发送参数的最简单方法:
String postURL = "http://www.example.com/page.php";
HttpPost post = new HttpPost(postURL);
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("id", "10"));
UrlEncodedFormEntity ent = new UrlEncodedFormEntity(params, "UTF-8");
post.setEntity(ent);
HttpClient client = new DefaultHttpClient();
HttpResponse responsePOST = client.execute(post);
你做完了 现在您可以使用了responsePOST
。以字符串形式获取响应内容:
BufferedReader reader = new BufferedReader(new InputStreamReader(responsePOST.getEntity().getContent()), 2048);
if (responsePOST != null) {
StringBuilder sb = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
System.out.println(" line : " + line);
sb.append(line);
}
String getResponseString = "";
getResponseString = sb.toString();
//use server output getResponseString as string value.
}
我建议使用基于apache http api构建的http-request。
HttpRequest<String> httpRequest = HttpRequestBuilder.createPost("http://www.example.com/page.php", String.class)
.responseDeserializer(ResponseDeserializer.ignorableDeserializer()).build();
public void send(){
String response = httpRequest.execute("id", "10").get();
}
PostMethod
它似乎实际上已经HttpPost
按照stackoverflow.com/a/9242394/1338936进行了调用-就像我这样找到答案的人一样:)