You can configure the HttpsURLConnection socket factory to accept all certificate without any validation:

private class TrustAll implements X509TrustManager
{
    public void checkClientTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException
    {
    }

    public void checkServerTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException
    {
    }

    public X509Certificate[] getAcceptedIssuers()
    {
        return new X509Certificate[0];
    }
}

SSLContext ctx = SSLContext.getInstance("TLS");
ctx.init(null, new TrustManager[] { new TrustAll() }, null);
HttpsURLConnection.setDefaultSSLSocketFactory(ctx.getSocketFactory());

UPDATE

You just have to call this code once at the start of the application. All HTTPS connections opened with URL.openConnection() will use this socket factory. Another solution could be adding this code in the createSSLSocket() method body.