Google Cloud Platform - Define credentials in code - google-cloud-platform

Question

How do we define credentials in Java program which connects to Google Cloud Platform to execute the code.
There is a standard way of setting GOOGLE_APPLICATION_CREDENTIALS env variable. I want to define in code. any suggestions?

Answer 1

Thanks for your response. Understood defining credentials is not recommended by GCP. So, I would use ADC(Authenticate Default Credentials).
Adding more info:
Providing credentials to your application
GCP client libraries use a strategy called Application Default Credentials (ADC) to find your application's credentials. When your code uses a client library, the strategy checks for your credentials in the following order:
First, ADC checks to see if the environment variable GOOGLE_APPLICATION_CREDENTIALS is set. If the variable is set, ADC uses the service account file that the variable points to.
If the environment variable isn't set, ADC uses the default service account that Compute Engine, Kubernetes Engine, App Engine, and Cloud Functions provide, for applications that run on those services.
If ADC can't use either of the above credentials, an error occurs.
The following code example illustrates this strategy. The example doesn't explicitly specify the application credentials. However, ADC is able to implicitly find the credentials as long as the GOOGLE_APPLICATION_CREDENTIALS environment variable is set, or as long as the application is running on Compute Engine, Kubernetes Engine, App Engine, or Cloud Functions.
Java Code:
static void authImplicit() {
// If you don't specify credentials when constructing the client, the client library will
// look for credentials via the environment variable GOOGLE_APPLICATION_CREDENTIALS.
Storage storage = StorageOptions.getDefaultInstance().getService();
System.out.println("Buckets:");
Page<Bucket> buckets = storage.list();
for (Bucket bucket : buckets.iterateAll()) {
System.out.println(bucket.toString());
}
}
You can find all these details in GCP link: https://cloud.google.com/docs/authentication/production#auth-cloud-app-engine-java