URLConnection is one of the methods used by java for http request. The specific implementation is:
public class HttpRequest {
/**
* 向指定URL发送GET方法的请求
*
* @param url
* 发送请求的URL
* @param param
* 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
* @return URL 所代表远程资源的响应结果
*/
public static String sendGet(String url, String param) {
String result = "";
BufferedReader in = null;
try {
String urlNameString = url + "?" + param;
URL realUrl = new URL(urlNameString);
// 打开和URL之间的连接
URLConnection connection = realUrl.openConnection();
// 设置通用的请求属性
connection.setRequestProperty("accept", "*/*");
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 建立实际的连接
connection.connect();
// 获取所有响应头字段
Map<String, List<String>> map = connection.getHeaderFields();
// 遍历所有的响应头字段
for (String key : map.keySet()) {
System.out.println(key + "--->" + map.get(key));
}
// 定义 BufferedReader输入流来读取URL的响应
in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
System.out.println("发送GET请求出现异常！" + e);
e.printStackTrace();
}
// 使用finally块来关闭输入流
finally {
try {
if (in != null) {
in.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
}
return result;
}
/**
* 向指定 URL 发送POST方法的请求
*
* @param url
* 发送请求的 URL
* @param param
* 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
* @return 所代表远程资源的响应结果
*/
public static String sendPost(String url, String param) {
PrintWriter out = null;
BufferedReader in = null;
String result = "";
try {
URL realUrl = new URL(url);
// 打开和URL之间的连接
URLConnection conn = realUrl.openConnection();
// 设置通用的请求属性
conn.setRequestProperty("accept", "*/*");
conn.setRequestProperty("connection", "Keep-Alive");
conn.setRequestProperty("Accept-Charset", "UTF-8");
conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 发送POST请求必须设置如下两行
conn.setConnectTimeout(10000);
conn.setReadTimeout(10000);
conn.setDoOutput(true);
conn.setDoInput(true);
// 获取URLConnection对象对应的输出流
out = new PrintWriter(conn.getOutputStream());
// 发送请求参数
out.print(param);
// flush输出流的缓冲
out.flush();
// 定义BufferedReader输入流来读取URL的响应
in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "utf-8"));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
System.out.println("发送 POST 请求出现异常！" + e);
e.printStackTrace();
MinaLog.log(">>>>>>>>>" + e.getMessage());
}
// 使用finally块来关闭输出流、输入流
finally {
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return result;
}
}When the request method is HTTPS, the signature needs to be processed to be compatible. The specific implementation method:
public class PostUtils {
/**
* 忽视证书HostName
*/
private static HostnameVerifier ignoreHostnameVerifier = new HostnameVerifier() {
public boolean verify(String s, SSLSession sslsession) {
//System.out.println("WARNING: Hostname is not matched for cert.");
return true;
}
};
/**
* Ignore Certification
*/
private static TrustManager ignoreCertificationTrustManger = new X509TrustManager() {
private X509Certificate[] certificates;
public void checkClientTrusted(X509Certificate certificates[],
String authType) throws CertificateException {
if (this.certificates == null) {
this.certificates = certificates;
//System.out.println("init at checkClientTrusted");
}
}
public void checkServerTrusted(X509Certificate[] ax509certificate,
String s) throws CertificateException {
if (this.certificates == null) {
this.certificates = ax509certificate;
//System.out.println("init at checkServerTrusted");
}
}
public X509Certificate[] getAcceptedIssuers() {
// TODO Auto-generated method stub
return null;
}
};
/**
* 获取UrlConn
*/
public static URLConnection geneUrlConn(String urlstr) throws Exception {
URL url = new URL(urlstr);
if(urlstr.startsWith("https://")){
HttpsURLConnection.setDefaultHostnameVerifier(ignoreHostnameVerifier);
HttpsURLConnection httpsConnection = (HttpsURLConnection) url.openConnection();
// Prepare SSL Context
TrustManager[] tm = { ignoreCertificationTrustManger };
SSLContext sslContext = SSLContext.getInstance("SSL", "SunJSSE");
sslContext.init(null, tm, new java.security.SecureRandom());
// 从上述SSLContext对象中得到SSLSocketFactory对象
SSLSocketFactory ssf = sslContext.getSocketFactory();
httpsConnection.setSSLSocketFactory(ssf);
return httpsConnection;
}
else {
return url.openConnection();
}
}
/**
* 发送POST请求
*
* @param url 请求地址url
* @param params 需要发送的请求参数字符串
* @param connTimeout 连接超时时间（毫秒），如果为null则默认为30秒
* @param readTimeout 读取超时时间（毫秒），如果为null则默认为60秒
* @return 请求响应内容，如果为null则表示请求异常
*/
public static String doPost(String url, String params, Integer connTimeout, Integer readTimeout, String contentType)
{
PrintWriter out = null;
BufferedReader in = null;
String result = "";
try
{
// URL realUrl = new URL(url);
// 打开和URL之间的连接,根据url
URLConnection conn = geneUrlConn(url);
// 设置通用的请求属性
conn.setRequestProperty("accept", "*/*");
conn.setRequestProperty("connection", "Keep-Alive");
conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
conn.setRequestProperty("Content-Type", contentType == null? "application/json" : contentType);
// 发送POST请求必须设置如下两行
conn.setDoOutput(true);
conn.setDoInput(true);
// 设置请求超时时间和读取超时时间
conn.setConnectTimeout(connTimeout == null ? 180 : connTimeout);
conn.setReadTimeout(readTimeout == null ? 180 : readTimeout);
// 获取URLConnection对象对应的输出流
out = new PrintWriter(new OutputStreamWriter(conn.getOutputStream(), "utf-8"));
// 发送请求参数
out.print(params);
// flush输出流的缓冲
out.flush();
// 定义BufferedReader输入流来读取URL的响应
in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "utf-8"));
String line;
while ((line = in.readLine()) != null)
result += line;
}
catch (Exception e)
{
e.printStackTrace();
result = null;
}
//使用finally块来关闭输出流、输入流
finally
{
try
{
if (out != null)
{
out.close();
}
if (in != null)
{
in.close();
}
}
catch (IOException ex)
{
ex.printStackTrace();
}
}
return result;
}
}And when passing parameters, if there are Chinese parameters, the parameters need to be encoded, namely URLEncoder.encode(param,"UTF-8")