public Builder clearFilePrefix() {
      filePrefix_ = getDefaultInstance().getFilePrefix();
      bitField0_ = (bitField0_ & ~0x00000002);
      onChanged();
      return this;
    }
<pre>
Required. File name prefix for the generated sprite sheets.

Each sprite sheet has an incremental 10-digit zero-padded suffix starting
from 0 before the extension, such as `sprite_sheet0000000123.jpeg`.
</pre>

<code>string file_prefix = 2 [(.google.api.field_behavior) = REQUIRED];</code>

@return This builder for chaining.
java-video-transcoder/proto-google-cloud-video-transcoder-v1/src/main/java/com/google/cloud/video/transcoder/v1/SpriteSheet.java