URLConnection是java用來http請求的方式之一，具體的實現方式爲：
public class HttpRequest {
/**
* 向指定URL發送GET方法的請求
*
* @param url
* 發送請求的URL
* @param param
* 請求參數，請求參數應該是 name1=value1&name2=value2 的形式。
* @return URL 所代表遠程資源的響應結果
*/
public static String sendGet(String url, String param) {
String result = "";
BufferedReader in = null;
try {
String urlNameString = url + "?" + param;
URL realUrl = new URL(urlNameString);
// 打開和URL之間的連接
URLConnection connection = realUrl.openConnection();
// 設置通用的請求屬性
connection.setRequestProperty("accept", "*/*");
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 建立實際的連接
connection.connect();
// 獲取所有響應頭字段
Map<String, List<String>> map = connection.getHeaderFields();
// 遍歷所有的響應頭字段
for (String key : map.keySet()) {
System.out.println(key + "--->" + map.get(key));
}
// 定義 BufferedReader輸入流來讀取URL的響應
in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
System.out.println("發送GET請求出現異常！" + e);
e.printStackTrace();
}
// 使用finally塊來關閉輸入流
finally {
try {
if (in != null) {
in.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
}
return result;
}
/**
* 向指定 URL 發送POST方法的請求
*
* @param url
* 發送請求的 URL
* @param param
* 請求參數，請求參數應該是 name1=value1&name2=value2 的形式。
* @return 所代表遠程資源的響應結果
*/
public static String sendPost(String url, String param) {
PrintWriter out = null;
BufferedReader in = null;
String result = "";
try {
URL realUrl = new URL(url);
// 打開和URL之間的連接
URLConnection conn = realUrl.openConnection();
// 設置通用的請求屬性
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)");
// 發送POST請求必須設置如下兩行
conn.setConnectTimeout(10000);
conn.setReadTimeout(10000);
conn.setDoOutput(true);
conn.setDoInput(true);
// 獲取URLConnection對象對應的輸出流
out = new PrintWriter(conn.getOutputStream());
// 發送請求參數
out.print(param);
// flush輸出流的緩衝
out.flush();
// 定義BufferedReader輸入流來讀取URL的響應
in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "utf-8"));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
System.out.println("發送 POST 請求出現異常！" + e);
e.printStackTrace();
MinaLog.log(">>>>>>>>>" + e.getMessage());
}
// 使用finally塊來關閉輸出流、輸入流
finally {
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return result;
}
}
當請求方式爲HTTPS時，需要對簽名做處理方可兼容，具體實現方式：
public class PostUtils {
/**
* 忽視證書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;
}
};
/**
* 獲取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());
// 從上述SSLContext對象中得到SSLSocketFactory對象
SSLSocketFactory ssf = sslContext.getSocketFactory();
httpsConnection.setSSLSocketFactory(ssf);
return httpsConnection;
}
else {
return url.openConnection();
}
}
/**
* 發送POST請求
*
* @param url 請求地址url
* @param params 需要發送的請求參數字符串
* @param connTimeout 連接超時時間（毫秒），如果爲null則默認爲30秒
* @param readTimeout 讀取超時時間（毫秒），如果爲null則默認爲60秒
* @return 請求響應內容，如果爲null則表示請求異常
*/
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);
// 打開和URL之間的連接,根據url
URLConnection conn = geneUrlConn(url);
// 設置通用的請求屬性
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);
// 發送POST請求必須設置如下兩行
conn.setDoOutput(true);
conn.setDoInput(true);
// 設置請求超時時間和讀取超時時間
conn.setConnectTimeout(connTimeout == null ? 180 : connTimeout);
conn.setReadTimeout(readTimeout == null ? 180 : readTimeout);
// 獲取URLConnection對象對應的輸出流
out = new PrintWriter(new OutputStreamWriter(conn.getOutputStream(), "utf-8"));
// 發送請求參數
out.print(params);
// flush輸出流的緩衝
out.flush();
// 定義BufferedReader輸入流來讀取URL的響應
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塊來關閉輸出流、輸入流
finally
{
try
{
if (out != null)
{
out.close();
}
if (in != null)
{
in.close();
}
}
catch (IOException ex)
{
ex.printStackTrace();
}
}
return result;
}
}
並且在進行參數傳遞時，如果出現有中文參數，需要對參數進行編碼處理，即 URLEncoder.encode( param,"UTF-8")