@Override
  @CanIgnoreReturnValue
  public KmsClient withCredentials(String credentialPath) throws GeneralSecurityException {
    try {
      if (credentialPath == null) {
        return withDefaultCredentials();
      }
      return withCredentialsProvider(new PropertiesFileCredentialsProvider(credentialPath));
    } catch (AmazonServiceException e) {
      throw new GeneralSecurityException("cannot load credentials", e);
    }
  }
Loads AWS credentials from a properties file.

<p>The AWS access key ID is expected to be in the <code>accessKey</code> property and the AWS
secret key is expected to be in the <code>secretKey</code> property.

@throws GeneralSecurityException if the client initialization fails
java_src/src/main/java/com/google/crypto/tink/integration/awskms/AwsKmsClient.java