Plaid Link for Android

import com.plaid.link.Plaid;
import com.plaid.linkbase.PlaidOptions;

public class MainApplication extends Application {

  @Override
  public void onCreate() {
    super.onCreate();

    Plaid.create(this);
  }
}

import java.util.ArrayList;
import android.content.Intent;
import androidx.appcompat.app.AppCompatActivity;

import com.plaid.link.LinkActivity;
import com.plaid.link.Plaid;
import com.plaid.linkbase.models.LinkConfiguration;
import com.plaid.linkbase.models.LinkEventListener;
import com.plaid.linkbase.models.PlaidApiError;
import com.plaid.linkbase.models.PlaidEnvironment;
import com.plaid.linkbase.models.PlaidProduct;

public class MainActivity extends AppCompatActivity {

  private static final int LINK_REQUEST_CODE = 1;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    // required
    String clientName = "My Application name";
    PlaidEnvironment environment = PlaidEnvironment.SANDBOX;
    ArrayList products = new ArrayList<>();
    products.add(PlaidProduct.TRANSACTIONS);

    // optional
    LinkEventListener linkEventListener = {}
    String language = Locale.ENGLISH.language;
    ArrayList countryCodes = new ArrayList<>();
    countryCodes.add(Locale.US.country);
    String webhook = "https://requestb.in";
    String userLegalName = "John Appleseed";
    String userEmailAddress = "jappleseed@example.net";

    Intent intent = new Intent(MainActivity.this,
                               LinkActivity.class);

    intent.putExtra(
      Plaid.LINK_CONFIGURATION,
      new LinkConfiguration(
        clientName,
        environment,
        products,
        linkEventListener,
        language,
        countryCodes,
        webhook,
        userLegalName,
        userEmailAddress
    ));

    startActivityForResult(intent, LINK_REQUEST_CODE);
  }
}

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

  private static final int LINK_REQUEST_CODE = 1;

  // configured in the previous step
  @Override
  public void onCreate() { ... }

  @Override
  protected void onActivityResult(
    int requestCode, int resultCode, @Nullable Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == LINK_REQUEST_CODE && data != null) {
      if (resultCode == Plaid.RESULT_SUCCESS) {
        // handle onSuccess
        // ...
      } else if (resultCode == Plaid.RESULT_EXIT) {
        // handle onExit
        // ...
      } else if (resultCode == Plaid.RESULT_CANCELLED) {
        // handle onCancelled
        // ...
      } else if (resultCode == Plaid.RESULT_EXCEPTION) {
        // handle onError
        // ...
      }
    } else {
      Log.i(this.getClass().getSimpleName(), "Not handled");
    }
  }
}

@Override
protected void onActivityResult(
int requestCode, int resultCode, @Nullable Intent data) {
  // ...
  if (requestCode == LINK_REQUEST_CODE && data != null) {

    // Handle onSuccess
    if (resultCode == Plaid.RESULT_SUCCESS) {
      LinkConnection item = (LinkConnection)
        data.getSerializableExtra(Plaid.LINK_RESULT);

      if (item != null) {
        // Send public_token to your server,
        // exchange for access_token
        String publicToken = item.getPublicToken();

        LinkConnectionMetadata metadata =
          item.getLinkConnectionMetadata();
        String accountId =
          metadata.getAccounts().get(0).getAccountId();
        String accountName =
          metadata.getAccounts().get(0).getAccountName();
        String accountNumber =
          metadata.getAccounts().get(0).getAccountNumber();
        String accountType =
          metadata.getAccounts().get(0).getAccountType();
        String accountType =
          metadata.getAccounts().get(0).getAccountSubType();
        String institutionId = metadata.getInstitutionId();
        String institutionName = metadata.getInstitutionName();
      }
    }
  }
}

@Override
protected void onActivityResult(
int requestCode, int resultCode, @Nullable Intent data) {
  // ...
  if (requestCode == LINK_REQUEST_CODE && data != null) {

    // Handle onExit
    if (resultCode == resultCode == Plaid.RESULT_EXIT) {
      PlaidApiError error = (PlaidApiError)
        data.getSerializableExtra(Plaid.LINK_RESULT);

      if (error != null) {
        String errorType = error.getErrorType()
        String errorCode = error.getErrorCode()
        String errorMessage = error.getErrorMessage();
        String displayMessage = error.getDisplayMessage();

        LinkExitMetadata metadata = error.getLinkExitMetadata();
        String institutionId = metadata.getInstitutionId();
        String institutionName = metadata.getInstitutionName();
        String status = metadata.getStatus();
    }
  }
}

@Override
protected void onActivityResult(
int requestCode, int resultCode, @Nullable Intent data) {
  // ...
  if (requestCode == LINK_REQUEST_CODE && data != null) {

    // Handle onCancelled
    if (resultCode == Plaid.RESULT_CANCELLED) {
      LinkCancellation cancellation = (LinkCancellation)
        data.getSerializableExtra(Plaid.LINK_RESULT);

      if (cancellation != null) {
        String insId = cancellation.getInstitutionId();
        String insName = cancellation.getInstitutionName();
        String linkSessionId = cancellation.getLinkSessionId();
        String status = cancellation.getStatus();
    }
  }
}

@Override
protected void onActivityResult(
int requestCode, int resultCode, @Nullable Intent data) {
  // ...
  if (requestCode == LINK_REQUEST_CODE && data != null) {

    // Handle onExit
    if (resultCode == Plaid.RESULT_EXCEPTION) {
      Exception exception =
        (Exception) data.getSerializableExtra(Plaid.LINK_RESULT);
      if (exception != null) {
        String errorClass = exception.getClass().toString();
        String message = exception.getMessage();
      }
    }
  }
}

@Override
protected void onCreate(Bundle savedInstanceState) {
  val linkEventListener = LinkEventListener {
    String event = linkEvent.getEvent();
  }

  intent.putExtra(
    Plaid.LINK_CONFIGURATION,
    new LinkConfiguration(
      // ...
      linkEventListener,
  ));
}

intent.putExtra(
  Plaid.LINK_CONFIGURATION,
  LinkConfiguration(
    ...,
    "<#GENERATED_PUBLIC_TOKEN#>",
    ...
  )
);

PlaidOptions plaidOptions =
  new PlaidOptions.Builder()
    .logLevel(BuildConfig.DEBUG ? LogLevel.DEBUG : LogLevel.ASSERT)
    .build();

Plaid.create(this, plaidOptions);