How to solve SSLHandshakeException in Android : SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version ?

Being android developers, we might have at least one time come across this issue >>

javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0xb8df4b50: Failure in SSL library, usually a protocol error
error:1407742E:SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version (external/openssl/ssl/s23_clnt.c:741 0x8d92d990:0x00000000)

or sometimes a similar variant of the above issue. What this actually means is that >>

"The server you are talking to is supporting only a specific protocol version which your client(your android app) is unaware of. That is, your client does not support that particular version"

The issue is mostly encountered in devices below lollipop i.e, kitkat and below devices. Let us see why the issue occurs.

Example Case :

Try getting some response from the host https://api.github.com/ like shown below

Retrofit retrofit1 = new Retrofit.Builder()
                .baseUrl("https://api.github.com/")
                .addConverterFactory(GsonConverterFactory.create())
                .build();


        GithubServise githubServise = retrofit1.create(GithubServise.class);

        Call<ResponseBody> call = githubServise.getGithub();
        call.enqueue(new Callback<ResponseBody>() {
            @Override
            public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
                Toast.makeText(MainActivity.this, "got response" , Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onFailure(Call<ResponseBody> call, Throwable t) {
                Toast.makeText(MainActivity.this, "SSL error?" , Toast.LENGTH_SHORT).show();
            }
        });

GithubServise.java

public interface GithubServise {
    @GET("/users/{pass_any_github_username_here}/repos")
    Call<ResponseBody> getGithub();
}

pass your github username in the interface as shown so that you could fetch your repos

You could make the following  observations while running this :

1. This code would run successfully without any issues from android api levels 20+(from lollipop onwards) and will fetch us a successful response with list of repos.
2.  This will not return any successfull response in the case of android devices below 20(kitkat(19) and below). The onFailure method will be executed with an error like this

javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0xb8df4b50: Failure in SSL library, usually a protocol errorerror:1407742E:SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version (external/openssl/ssl/s23_clnt.c:741 0x8d92d990:0x00000000)

The reason why this is working only in devices with api levels 20+ is that the host  https://api.github.com/ supports only TLS 1.2 which is by default disabled in android devices below 20.

You can see the list of protocols supported by your web server by going here https://www.ssllabs.com/ssltest/ and typing in https://api.github.com/ inside hostname field.