public java.lang.String getOutputUriPrefix() {
      java.lang.Object ref = outputUriPrefix_;
      if (!(ref instanceof java.lang.String)) {
        com.google.protobuf.ByteString bs = (com.google.protobuf.ByteString) ref;
        java.lang.String s = bs.toStringUtf8();
        outputUriPrefix_ = s;
        return s;
      } else {
        return (java.lang.String) ref;
      }
    }
<pre>
Required. There must be no files under 'output_uri_prefix'.
'output_uri_prefix' must end with "/" and start with "gs://", otherwise an
INVALID_ARGUMENT (400) error is returned.
</pre>

<code>string output_uri_prefix = 1 [(.google.api.field_behavior) = REQUIRED];</code>

@return The outputUriPrefix.
java-translate/proto-google-cloud-translate-v3beta1/src/main/java/com/google/cloud/translate/v3beta1/GcsDestination.java