Using Scribe's custom RequestFactory and ConnectionFactory

XeroOAuthService.java

import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;

import javax.net.ssl.HttpsURLConnection;

import org.scribe.builder.api.DefaultApi10a;
import org.scribe.model.OAuthConfig;
import org.scribe.model.OAuthConstants;
import org.scribe.model.OAuthRequest;
import org.scribe.model.Token;
import org.scribe.model.Verb;
import org.scribe.model.Verifier;
import org.scribe.oauth.OAuth10aServiceImpl;
import org.scribe.services.DefaultConnectionFactory;
import org.scribe.services.RequestFactory;

public class XeroOAuthService extends OAuth10aServiceImpl implements TokenRefresher
{
    public static class Context
    {
        public XeroToken oldToken;
        public boolean forRefresh;
    }

    private final XeroOAuthService.Context context;
    
    public XeroOAuthService(final DefaultApi10a api, OAuthConfig config, final XeroOAuthService.Context context)
    {
        super(api, config, new RequestFactory()
        {
            @Override
            public OAuthRequest createRequest(Verb verb, String url)
            {
                OAuthRequest request = new OAuthRequest(verb, url, new DefaultConnectionFactory()
                {
                    @Override
                    public HttpURLConnection createConnection(String url) throws MalformedURLException, IOException
                    {
                        HttpsURLConnection connection = (HttpsURLConnection) super.createConnection(url);
                        XeroPartnerApi partnerApi = (XeroPartnerApi) api;
                        connection.setSSLSocketFactory(partnerApi.getSslContext().getSocketFactory());
                        return connection;
                    }
                });
                
                if (context.forRefresh)
                {
                    request.addOAuthParameter(
                            OAuthConstants.SESSION_HANDLE,
                            context.oldToken.getOauthSessionHandle());
                }
                
                return request;
            }
        });
        
        this.context = context;
    }
    
    @SuppressWarnings("unchecked")
    @Override
    public <T extends Jsonable> T refreshToken(T token)
    {
        XeroToken xeroToken = (XeroToken) token;
        
        try
        {
            context.forRefresh = true;
            context.oldToken = xeroToken;
            
            //  We renew token by getting new access token and passing oauth_session_handle
            //  http://oauth.googlecode.com/svn/spec/ext/session/1.0/drafts/1/spec.html#rfc.section.5.3
            
            Token newToken = getAccessToken(
                    new Token(xeroToken.getOauthToken(), xeroToken.getOauthTokenSecret()),
                    new Verifier("ignored"));
            
            return (T) XeroToken.fromRawResponse(newToken.getRawResponse());
        }
        finally
        {
            context.forRefresh = false;
            context.oldToken = null;
        }
    }
}