Add list recommendations code sample

[ouitavon]

No description provided.

[kurtisvg]

Preferable we can point to the "Setting up a Java environment" page on GCP which is a little more detailed on what the need for their environment.

[ouitavon]

Done, linked to Setting up a Java environment page for the first step.

[kurtisvg]

Please add a no-arg, overloaded function for this - see Function Structure

[kurtisvg]

If location isn't required for testing (looks like it's set to global atm), please just inline in the sample (and add a comment with a link to where the rules around what region can be specified for recommender's

[ouitavon]

Sounds good. Went ahead and just use global and google.iam.policy.Recommender as default location and recommender.

[kurtisvg]

For snippets, we strongly prefer not to include CLI parsing as part of the snippet for maintenance reasons. Most users will find the sample from the docs for the snippet, and most often copy/paste the sample and use their IDE to execute - See Exception Handling

[ouitavon]

Done.

[kurtisvg]

IOException is usually a low level file/networking error and should be allowed to bubble up - we only want to catch errors if it's a response from the service or if it's something we are going to show the user how to recover from - see Exception Handling

[ouitavon]

Done, letting error bubble up.

[kurtisvg]

This looks better, but please separate out the call from the iteration to make more clear. Often users are unsure when the API call actually happens with built requests, so it's helpful to be specific:

// Send the request to the service and receive the response
List<Recommendation> response = recommenderClient.listRecommendations(request);

// Print each recommendation
for (Recommendation recommendation : response.iterateAll()) {
  // ...
}
System.out.println("List recommendations successful");

[ouitavon]

Separated out the request from the print loop.

[kurtisvg]

Please enclose with a try-with-resources and add the comment from the Sample Format guide regarding using .close():

// Initialize client that will be used to send requests. This client only needs to be created
// once, and can be reused for multiple requests. After completing all of your requests, call
// the "close" method on the client to safely clean up any remaining background resources.
try (DlpServiceClient dlp = DlpServiceClient.create()) {
  // Do something
}

[ouitavon]

Done.

[kurtisvg]

Assume the user wants to edit inline and run from IDE:

Suggested change

	String projectId = System.getenv("GOOGLE_CLOUD_PROJECT");
	// TODO(developer): Replace these variables before running the sample.
	String projectId = "my-project-id";

[ouitavon]

Done.

[kurtisvg]

Should exclude main altogether - users can run the snippet by replacing the variables in the no-arg function call and triggering themselves.

[ouitavon]

Done, also removed option to run from main in the readme.

[kurtisvg]

You'll need to update to listRecommendations(String projectId, String location, String recommender) - When move the env vars to this side, make sure to throw an error if they aren't there. See this example.

[ouitavon]

Updated and added env var checks.