HttpClient请求https的实例：

package train;import java.io.IOException;import java.security.NoSuchAlgorithmException;import java.security.cert.CertificateException;import java.security.cert.X509Certificate;import javax.net.ssl.SSLContext;import javax.net.ssl.TrustManager;import javax.net.ssl.X509TrustManager;import org.apache.http.client.ClientProtocolException;import org.apache.http.client.HttpClient;import org.apache.http.client.ResponseHandler;import org.apache.http.client.methods.HttpGet;import org.apache.http.conn.ClientConnectionManager;import org.apache.http.conn.scheme.Scheme;import org.apache.http.conn.scheme.SchemeRegistry;import org.apache.http.conn.ssl.SSLSocketFactory;import org.apache.http.impl.client.BasicResponseHandler;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.params.HttpParams;public class train {    public static void main(String args[]) {        try {            HttpClient httpclient = new DefaultHttpClient();            // Secure Protocol implementation.            SSLContext ctx = SSLContext.getInstance("SSL");            // Implementation of a trust manager for X509 certificates            X509TrustManager tm = new X509TrustManager() {                public void checkClientTrusted(X509Certificate[] xcs, String string) throws CertificateException {                }                public void checkServerTrusted(X509Certificate[] xcs, String string) throws CertificateException {                }                public X509Certificate[] getAcceptedIssuers() {                    return null;                }            };            ctx.init(null, new TrustManager[] { tm }, null);            SSLSocketFactory ssf = new SSLSocketFactory(ctx);            ClientConnectionManager ccm = httpclient.getConnectionManager();            // register https protocol in httpclient's scheme registry            SchemeRegistry sr = ccm.getSchemeRegistry();            sr.register(new Scheme("https", 443, ssf));            HttpGet httpget = new HttpGet(                    "https://kyfw.12306.cn/otn/lcxxcx/query?purpose_codes=ADULT&queryDate=2016-08-23&from_station=BJP&to_station=TJP");            HttpParams params = httpclient.getParams();            System.out.println("Request URL:" + httpget.getURI());            ResponseHandler responseHandler = new BasicResponseHandler();            String responseBody = (String) httpclient.execute(httpget, responseHandler);                        System.out.println(responseBody);            // Create a response handler        } catch (NoSuchAlgorithmException e) {            // TODO Auto-generated catch block            e.printStackTrace();        } catch (ClientProtocolException e) {            // TODO Auto-generated catch block            e.printStackTrace();        } catch (IOException e) {            // TODO Auto-generated catch block            e.printStackTrace();        } catch (Exception ex) {            ex.printStackTrace();        }    }}