How to Integrate Google Plus Login with android.

GooglePlusLogin.Java

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.support.v4.app.FragmentActivity;

import com.apptcom.external.logging.Logger;
import com.apptcom.external.model.UserSocialModel;
import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.auth.api.signin.GoogleSignInResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.OptionalPendingResult;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.plus.Plus;
import com.google.android.gms.plus.model.people.Person;

import java.lang.ref.WeakReference;

public class GooglePlusLogin {

    public static final int GOOGLE_SIGN_IN = 9001;
    private GoogleApiClient mGoogleApiClient;
    private WeakReference<Context> weakReference;
    private GoogleApiClient.OnConnectionFailedListener mOnConnectionFailedListener;
    private GooglePlusLoginListener successListener;

    public GooglePlusLogin(Context context, GoogleApiClient.OnConnectionFailedListener onConnectionFailedListener) {
        this.weakReference = new WeakReference<>(context);
        this.mOnConnectionFailedListener = onConnectionFailedListener;

    }


    public GoogleApiClient getGoogleApiClient() {
        return mGoogleApiClient;
    }

    public void setOnSuccessListener(GooglePlusLoginListener successListener) {
        this.successListener = successListener;
    }


    public void setupGooglePlusClient() {
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .build();
        if (mGoogleApiClient == null)
            mGoogleApiClient = new GoogleApiClient.Builder(weakReference.get())
                    .enableAutoManage((FragmentActivity) weakReference.get(), mOnConnectionFailedListener)
                    .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
                    .addApi(Plus.API, Plus.PlusOptions.builder().build())
                    .build();
    }


    public void loginWithGooglePlus() {
        if (mGoogleApiClient != null) {
            OptionalPendingResult<GoogleSignInResult> opr = Auth.GoogleSignInApi.silentSignIn(mGoogleApiClient);
            if (opr.isDone()) {
                logOutGooglePlusConnection();
            }
        }
        Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
        ((Activity) weakReference.get()).startActivityForResult(signInIntent, GOOGLE_SIGN_IN);
    }

    public void onActivityResultSuccess(Intent data) {
        GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
        handleSignInResult(result);
    }

    private void handleSignInResult(GoogleSignInResult result) {
        UserSocialModel userModel;
        if (result.isSuccess()) {
            userModel = new UserSocialModel();
            GoogleSignInAccount userAccount = result.getSignInAccount();
            userModel.name = userAccount.getDisplayName();
            userModel.email = userAccount.getEmail();
            userModel.photo = userAccount.getPhotoUrl().toString();

            try {
                Person currentPerson = Plus.PeopleApi.getCurrentPerson(mGoogleApiClient);
                userModel.about = currentPerson.getAboutMe();
                userModel.link = currentPerson.getUrl();
                userModel.currentCity = currentPerson.getCurrentLocation();
                if (currentPerson.hasOrganizations())
                    userModel.work = currentPerson.getOrganizations().get(0).getName();
            } catch (Exception error) {
                Logger.error("GooglePlusLogin", "Error while getting Plus.PeopleApi.getCurrentPerson");
            }
            if (successListener != null)
                successListener.onGooglePlusSuccess(userModel);
        }
    }
    
    public void logOutGooglePlusConnection() {
        if (mGoogleApiClient.isConnected()) {
            Auth.GoogleSignInApi.signOut(mGoogleApiClient).setResultCallback(
                    new ResultCallback<Status>() {
                        @Override
                        public void onResult(Status status) {
                        }
                    });
            Auth.GoogleSignInApi.revokeAccess(mGoogleApiClient).setResultCallback(
                    new ResultCallback<Status>() {
                        @Override
                        public void onResult(Status status) {
                        }
                    });
        }
    }

    public interface GooglePlusLoginListener {
        void onGooglePlusSuccess(UserSocialModel userModel);
    }

}