public java.lang.String getBackup() {
        java.lang.Object ref = backup_;
        if (!(ref instanceof java.lang.String)) {
          com.google.protobuf.ByteString bs = (com.google.protobuf.ByteString) ref;
          java.lang.String s = bs.toStringUtf8();
          backup_ = s;
          return s;
        } else {
          return (java.lang.String) ref;
        }
      }
<pre>
Optional. Example:
//memorystore.googleapis.com/projects/{project}/locations/{location}/backupCollections/{collection}/backups/{backup}
A shorter version (without the prefix) of the backup name is also
supported, like
projects/{project}/locations/{location}/backupCollections/{collection}/backups/{backup_id}
In this case, it assumes the backup is under memorystore.googleapis.com.
</pre>

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

@return The backup.
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/Instance.java