Can not find ImmutableValidateConnectorRuntimeSettingsResponse, ImmutableValidateCredentialsResponse and ImmutableDescribeConnectorConfigurationResponse

Hi, I wanted to implement custom connector using the Java SDK.
When I was going through the code, I found that few files are missing.

import com.amazonaws.appflow.custom.connector.model.connectorconfiguration.ImmutableDescribeConnectorConfigurationResponse;
import com.amazonaws.appflow.custom.connector.model.credentials.ImmutableValidateCredentialsResponse;
import com.amazonaws.appflow.custom.connector.model.settings.ImmutableValidateConnectorRuntimeSettingsResponse;
import com.amazonaws.appflow.custom.connector.model.ImmutableErrorDetails;

And when I am trying to build the project I am getting lot of exceptions like
error: Line contains carriage return

Start with the Java SDK build and the imports for ImmutableValidateConnectorRuntimeSettingsResponse, ImmutableValidateCredentialsResponse, ImmutableDescribeConnectorConfigurationResponse, and ImmutableErrorDetails. Check why these referenced classes are unavailable and where the carriage-return build errors originate. Done means the imports resolve and the project builds without those exceptions.

Written by the indexing model from the issue text.