Where can I get “serviceAccountCredentials.json” for Firebase Admin?

Here is said what I need to set up Firebase on java:

FirebaseOptions options = new FirebaseOptions.Builder()
    .setDatabaseUrl("https://databaseName.firebaseio.com")
    .setServiceAccount(new FileInputStream("path/to/serviceAccountCredentials.json"))
    .build();
FirebaseApp.initializeApp(options);

But where can I get serviceAccountCredentials.json ?

UPDATED: I found that this file seems should have this fields, but where get this values?

{
  "type": "",
  "project_id": "",
  "private_key_id": "",
  "private_key": "",
  "client_email": "",
  "client_id": "",
  "auth_uri": "",
  "token_uri": "",
  "auth_provider_x509_cert_url": "",
  "client_x509_cert_url": ""
}

Answer

Found details about this in this link

[UPDATED 30.11.2021]

To generate a private key file for your service account:

In the Firebase console, open Settings > Service Accounts.

Click Generate New Private Key, then confirm by clicking Generate Key.

Securely store the JSON file containing the key.

When authorizing via a service account, you have two choices for providing the credentials to your application. You can either set the GOOGLE_APPLICATION_CREDENTIALS environment variable, or you can explicitly pass the path to the service account key in code. The first option is more secure and is strongly recommended.

NB: When you generate a new private key, the old key will stop working immediately

To create the a new private key file you need to go to this link

https://console.firebase.google.com/project/**YOUR_PROJECT**/settings/serviceaccounts/adminsdk

[OLD]

Quote from firebase docs:

2. Navigate to the Service Accounts tab in your project’s settings page.
3. Click the Generate New Private Key button at the bottom of the Firebase Admin SDK section of the Service Accounts tab.

After you click the button, a JSON file containing your service account’s credentials will be downloaded. You’ll need this to initialize the SDK in the next step.

Warning: Use extra caution when handling service account credentials in your code. Do not commit them to a public repository, deploy them in a client app, or expose them in any way that could compromise the security of your Firebase project.

This file is only generated once. If you lose or leak the key, you can repeat the instructions above to create a new JSON key for the service account.