public Builder setInputKeyBytes(com.google.protobuf.ByteString value) {
        if (value == null) {
          throw new NullPointerException();
        }
        checkByteStringIsUtf8(value);
        inputKey_ = value;
        bitField0_ |= 0x00000002;
        onChanged();
        return this;
      }
<pre>
Required. The `Input.key` that identifies the input file.
</pre>

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

@param value The bytes for inputKey to set.
@return This builder for chaining.
java-video-transcoder/proto-google-cloud-video-transcoder-v1/src/main/java/com/google/cloud/video/transcoder/v1/AudioStream.java