Provides access to secure url connections; given certificate as specified by java.security.cert.CertificateFactory#generateCertificate

HttpsURLConnectionFactory.java

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package com.forrst.java.twKo;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.nio.charset.Charset;
import java.security.KeyStore;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;

import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManagerFactory;

/**
 * @author Markos Charatzas [http://forrst.me/Cue]
 *
 * @date Sep 10, 2011
 */
public final class HttpsURLConnectionFactory 
{
	/*
	 * 
	 */
	private static SSLSocketFactory newSSLSocketFactory(InputStream certificateStream)
	{
		try {
			CertificateFactory cf = CertificateFactory.getInstance("X.509");
			Certificate certificate = cf.generateCertificate(certificateStream);

			KeyStore keystore = 
					KeyStore.getInstance( KeyStore.getDefaultType() );
			
			keystore.setCertificateEntry("foo", certificate);

			String defaultAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
			
			TrustManagerFactory tmf = 
					TrustManagerFactory.getInstance(defaultAlgorithm);
				
			tmf.init(keystore);
			SSLContext ctx = SSLContext.getInstance("TLS");
			ctx.init(null, tmf.getTrustManagers(), null);
			
		return ctx.getSocketFactory();
		} 
		catch (Exception e) {
			throw new RuntimeException(e);
		}
	}

	/**
	 * 
	 * @param certificate the full certificate as String. Needs to be UTF-8 encoded.
	 * @param urlScheme the full url e.g. https://www.example.com
	 * @param type method type of {GET, POST}
	 * @return an established {@link HttpsURLConnection} ready to read from
	 * @throws IOException if the urlsceme is malformed or there is an error 
	 * opening the connection 
	 */
	public static HttpsURLConnection newSecureHttpConnection(String certificate, String urlScheme, String type) throws IOException 
	{
		InputStream certificateStream = 
				new ByteArrayInputStream(certificate.getBytes(Charset.forName("UTF-8")));

		SSLSocketFactory sslFactory = newSSLSocketFactory(certificateStream);
		
		URL url = new URL(urlScheme);
		HttpsURLConnection conn = (HttpsURLConnection)url.openConnection();
		conn.setSSLSocketFactory(sslFactory);
		conn.setRequestMethod(type);
		
	return conn;
	}
}