Several common types of java sending http request instances
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/**
* @Description: Send http request help class
* @author:liuyc
* @time: May 17, 2016 at 3:25:32 pm
*/
public class HttpClientHelper {
/**
* @Description: Send post request using HttpURLConnection
* @author:liuyc
* @time: May 17, 2016 at 3:26:07 pm
*/
public static String sendPost(String urlParam, Map<String, Object> params, String charset) {
StringBuffer resultBuffer = null;
// Build request parameters StringBuffer sbParams = new StringBuffer();
if (params != null && () > 0) {
for (Entry<String, Object> e : ()) {
(());
("=");
(());
("&");
}
}
HttpURLConnection con = null;
OutputStreamWriter osw = null;
BufferedReader br = null;
// Send a request try {
URL url = new URL(urlParam);
con = (HttpURLConnection) ();
("POST");
(true);
(true);
(false);
("Content-Type", "application/x-www-form-urlencoded");
if (sbParams != null && () > 0) {
osw = new OutputStreamWriter((), charset);
((0, () - 1));
();
}
// Read the return content resultBuffer = new StringBuffer();
int contentLength = (("Content-Length"));
if (contentLength > 0) {
br = new BufferedReader(new InputStreamReader((), charset));
String temp;
while ((temp = ()) != null) {
(temp);
}
}
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (osw != null) {
try {
();
} catch (IOException e) {
osw = null;
throw new RuntimeException(e);
} finally {
if (con != null) {
();
con = null;
}
}
}
if (br != null) {
try {
();
} catch (IOException e) {
br = null;
throw new RuntimeException(e);
} finally {
if (con != null) {
();
con = null;
}
}
}
}
return ();
}
/**
* @Description: Use URLConnection to send post
* @author:liuyc
* @time: May 17, 2016 at 3:26:52 pm
*/
public static String sendPost2(String urlParam, Map<String, Object> params, String charset) {
StringBuffer resultBuffer = null;
// Build request parameters StringBuffer sbParams = new StringBuffer();
if (params != null && () > 0) {
for (Entry<String, Object> e : ()) {
(());
("=");
(());
("&");
}
}
URLConnection con = null;
OutputStreamWriter osw = null;
BufferedReader br = null;
try {
URL realUrl = new URL(urlParam);
// Open the connection to the URL con = ();
// Set common request attributes ("accept", "*/*");
("connection", "Keep-Alive");
("Content-Type", "application/x-www-form-urlencoded");
("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");
// The following two lines must be set to send a POST request
(true);
(true);
// Get the output stream corresponding to the URLConnection object
osw = new OutputStreamWriter((), charset);
if (sbParams != null && () > 0) {
// Send request parameters
((0, () - 1));
// Buffer of flush output stream
();
}
// Define the BufferedReader input stream to read the URL response
resultBuffer = new StringBuffer();
int contentLength = (("Content-Length"));
if (contentLength > 0) {
br = new BufferedReader(new InputStreamReader((), charset));
String temp;
while ((temp = ()) != null) {
(temp);
}
}
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (osw != null) {
try {
();
} catch (IOException e) {
osw = null;
throw new RuntimeException(e);
}
}
if (br != null) {
try {
();
} catch (IOException e) {
br = null;
throw new RuntimeException(e);
}
}
}
return ();
}
/**
* @Description: Send get request to save download file
* @author:liuyc
* @time: May 17, 2016 at 3:27:29 pm
*/
public static void sendGetAndSaveFile(String urlParam, Map<String, Object> params, String fileSavePath) {
// Build request parameters StringBuffer sbParams = new StringBuffer();
if (params != null && () > 0) {
for (Entry<String, Object> entry : ()) {
(());
("=");
(());
("&");
}
}
HttpURLConnection con = null;
BufferedReader br = null;
FileOutputStream os = null;
try {
URL url = null;
if (sbParams != null && () > 0) {
url = new URL(urlParam + "?" + (0, () - 1));
} else {
url = new URL(urlParam);
}
con = (HttpURLConnection) ();
("Content-Type", "application/x-www-form-urlencoded");
();
InputStream is = ();
os = new FileOutputStream(fileSavePath);
byte buf[] = new byte[1024];
int count = 0;
while ((count = (buf)) != -1) {
(buf, 0, count);
}
();
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (os != null) {
try {
();
} catch (IOException e) {
os = null;
throw new RuntimeException(e);
} finally {
if (con != null) {
();
con = null;
}
}
}
if (br != null) {
try {
();
} catch (IOException e) {
br = null;
throw new RuntimeException(e);
} finally {
if (con != null) {
();
con = null;
}
}
}
}
}
/**
* @Description: Send get request using HttpURLConnection
* @author:liuyc
* @time: May 17, 2016 at 3:27:29 pm
*/
public static String sendGet(String urlParam, Map<String, Object> params, String charset) {
StringBuffer resultBuffer = null;
// Build request parameters StringBuffer sbParams = new StringBuffer();
if (params != null && () > 0) {
for (Entry<String, Object> entry : ()) {
(());
("=");
(());
("&");
}
}
HttpURLConnection con = null;
BufferedReader br = null;
try {
URL url = null;
if (sbParams != null && () > 0) {
url = new URL(urlParam + "?" + (0, () - 1));
} else {
url = new URL(urlParam);
}
con = (HttpURLConnection) ();
("Content-Type", "application/x-www-form-urlencoded");
();
resultBuffer = new StringBuffer();
br = new BufferedReader(new InputStreamReader((), charset));
String temp;
while ((temp = ()) != null) {
(temp);
}
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (br != null) {
try {
();
} catch (IOException e) {
br = null;
throw new RuntimeException(e);
} finally {
if (con != null) {
();
con = null;
}
}
}
}
return ();
}
/**
* @Description: Use URLConnection to send a get request
* @author:liuyc
* @time: May 17, 2016 at 3:27:58 pm
*/
public static String sendGet2(String urlParam, Map<String, Object> params, String charset) {
StringBuffer resultBuffer = null;
// Build request parameters StringBuffer sbParams = new StringBuffer();
if (params != null && () > 0) {
for (Entry<String, Object> entry : ()) {
(());
("=");
(());
("&");
}
}
BufferedReader br = null;
try {
URL url = null;
if (sbParams != null && () > 0) {
url = new URL(urlParam + "?" + (0, () - 1));
} else {
url = new URL(urlParam);
}
URLConnection con = ();
// Set request properties ("accept", "*/*");
("connection", "Keep-Alive");
("Content-Type", "application/x-www-form-urlencoded");
("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");
// Create a connection
();
resultBuffer = new StringBuffer();
br = new BufferedReader(new InputStreamReader((), charset));
String temp;
while ((temp = ()) != null) {
(temp);
}
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (br != null) {
try {
();
} catch (IOException e) {
br = null;
throw new RuntimeException(e);
}
}
}
return ();
}
/**
* @Description: Send post request using HttpClient
* @author:liuyc
* @time: May 17, 2016 at 3:28:23 pm
*/
public static String httpClientPost(String urlParam, Map<String, Object> params, String charset) {
StringBuffer resultBuffer = null;
HttpClient client = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(urlParam);
// Build request parameters List<NameValuePair> list = new ArrayList<NameValuePair>();
Iterator<Entry<String, Object>> iterator = ().iterator();
while (()) {
Entry<String, Object> elem = ();
(new BasicNameValuePair((), (())));
}
BufferedReader br = null;
try {
if (() > 0) {
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(list, charset);
(entity);
}
HttpResponse response = (httpPost);
// Read server response data resultBuffer = new StringBuffer();
br = new BufferedReader(new InputStreamReader(().getContent()));
String temp;
while ((temp = ()) != null) {
(temp);
}
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (br != null) {
try {
();
} catch (IOException e) {
br = null;
throw new RuntimeException(e);
}
}
}
return ();
}
/**
* @Description: Send get request using HttpClient
* @author:liuyc
* @time: May 17, 2016 at 3:28:56 pm
*/
public static String httpClientGet(String urlParam, Map<String, Object> params, String charset) {
StringBuffer resultBuffer = null;
HttpClient client = new DefaultHttpClient();
BufferedReader br = null;
// Build request parameters StringBuffer sbParams = new StringBuffer();
if (params != null && () > 0) {
for (Entry<String, Object> entry : ()) {
(());
("=");
try {
(((()), charset));
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e);
}
("&");
}
}
if (sbParams != null && () > 0) {
urlParam = urlParam + "?" + (0, () - 1);
}
HttpGet httpGet = new HttpGet(urlParam);
try {
HttpResponse response = (httpGet);
// Read server response data br = new BufferedReader(new InputStreamReader(().getContent()));
String temp;
resultBuffer = new StringBuffer();
while ((temp = ()) != null) {
(temp);
}
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (br != null) {
try {
();
} catch (IOException e) {
br = null;
throw new RuntimeException(e);
}
}
}
return ();
}
/**
* @Description: Use socket to send post request
* @author:liuyc
* @time: May 18, 2016 at 9:26:22 am
*/
public static String sendSocketPost(String urlParam, Map<String, Object> params, String charset) {
String result = "";
// Build request parameters StringBuffer sbParams = new StringBuffer();
if (params != null && () > 0) {
for (Entry<String, Object> entry : ()) {
(());
("=");
(());
("&");
}
}
Socket socket = null;
OutputStreamWriter osw = null;
InputStream is = null;
try {
URL url = new URL(urlParam);
String host = ();
int port = ();
if (-1 == port) {
port = 80;
}
String path = ();
socket = new Socket(host, port);
StringBuffer sb = new StringBuffer();
("POST " + path + " HTTP/1.1\r\n");
("Host: " + host + "\r\n");
("Connection: Keep-Alive\r\n");
("Content-Type: application/x-www-form-urlencoded; charset=utf-8 \r\n");
("Content-Length: ").append(().getBytes().length).append("\r\n");
// Here is a carriage return line break, which means that the message header is finished, otherwise the server will continue to wait ("\r\n");
if (sbParams != null && () > 0) {
((0, () - 1));
}
osw = new OutputStreamWriter(());
(());
();
is = ();
String line = null;
// Server response volume data length int contentLength = 0;
// Read the header information of http response do {
line = readLine(is, 0, charset);
if (("Content-Length")) {
// Get the length of the response body contentLength = ((":")[1].trim());
}
// If a separate carriage return line break is encountered, the request header ends } while (!("\r\n"));
// Read out the response body data (that is the data you want) result = readLine(is, contentLength, charset);
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (osw != null) {
try {
();
} catch (IOException e) {
osw = null;
throw new RuntimeException(e);
} finally {
if (socket != null) {
try {
();
} catch (IOException e) {
socket = null;
throw new RuntimeException(e);
}
}
}
}
if (is != null) {
try {
();
} catch (IOException e) {
is = null;
throw new RuntimeException(e);
} finally {
if (socket != null) {
try {
();
} catch (IOException e) {
socket = null;
throw new RuntimeException(e);
}
}
}
}
}
return result;
}
/**
* @Description: Use socket to send a get request
* @author:liuyc
* @time: May 18, 2016 at 9:27:18 am
*/
public static String sendSocketGet(String urlParam, Map<String, Object> params, String charset) {
String result = "";
// Build request parameters StringBuffer sbParams = new StringBuffer();
if (params != null && () > 0) {
for (Entry<String, Object> entry : ()) {
(());
("=");
(());
("&");
}
}
Socket socket = null;
OutputStreamWriter osw = null;
InputStream is = null;
try {
URL url = new URL(urlParam);
String host = ();
int port = ();
if (-1 == port) {
port = 80;
}
String path = ();
socket = new Socket(host, port);
StringBuffer sb = new StringBuffer();
("GET " + path + " HTTP/1.1\r\n");
("Host: " + host + "\r\n");
("Connection: Keep-Alive\r\n");
("Content-Type: application/x-www-form-urlencoded; charset=utf-8 \r\n");
("Content-Length: ").append(().getBytes().length).append("\r\n");
// Here is a carriage return line break, which means that the message header is finished, otherwise the server will continue to wait ("\r\n");
if (sbParams != null && () > 0) {
((0, () - 1));
}
osw = new OutputStreamWriter(());
(());
();
is = ();
String line = null;
// Server response volume data length int contentLength = 0;
// Read the header information of http response do {
line = readLine(is, 0, charset);
if (("Content-Length")) {
// Get the length of the response body contentLength = ((":")[1].trim());
}
// If a separate carriage return line break is encountered, the request header ends } while (!("\r\n"));
// Read out the response body data (that is the data you want) result = readLine(is, contentLength, charset);
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (osw != null) {
try {
();
} catch (IOException e) {
osw = null;
throw new RuntimeException(e);
} finally {
if (socket != null) {
try {
();
} catch (IOException e) {
socket = null;
throw new RuntimeException(e);
}
}
}
}
if (is != null) {
try {
();
} catch (IOException e) {
is = null;
throw new RuntimeException(e);
} finally {
if (socket != null) {
try {
();
} catch (IOException e) {
socket = null;
throw new RuntimeException(e);
}
}
}
}
}
return result;
}
/**
* @Description: Read a line of data. When the contentLe content length is 0, read the response header information. When it is not 0, read the main text.
* @time: May 17, 2016 at 6:11:07 pm
*/
private static String readLine(InputStream is, int contentLength, String charset) throws IOException {
List<Byte> lineByte = new ArrayList<Byte>();
byte tempByte;
int cumsum = 0;
if (contentLength != 0) {
do {
tempByte = (byte) ();
((tempByte));
cumsum++;
} while (cumsum < contentLength);// cumsum equals contentLength means that it has been read } else {
do {
tempByte = (byte) ();
((tempByte));
} while (tempByte != 10);// The ascii code value of the newline character is 10 }
byte[] resutlBytes = new byte[()];
for (int i = 0; i < (); i++) {
resutlBytes[i] = ((i)).byteValue();
}
return new String(resutlBytes, charset);
}
}The above four methods can send get and post requests respectively
- The first type: HttpURLConnection,
- Type 2: URLConnection,
- The third type: HttpClient,
- The 4th type: Socket. Friends should note that when using the 3rd type HttpClient, it is necessary to rely on three jar packages, namely: commons-logging-1.0., and httpcore-4.1.
Summarize
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