public Builder mergeNegativeExpireTime(com.google.protobuf.Timestamp value) {
      if (negativeExpireTimeBuilder_ == null) {
        if (((bitField0_ & 0x00000002) != 0)
            && negativeExpireTime_ != null
            && negativeExpireTime_ != com.google.protobuf.Timestamp.getDefaultInstance()) {
          getNegativeExpireTimeBuilder().mergeFrom(value);
        } else {
          negativeExpireTime_ = value;
        }
      } else {
        negativeExpireTimeBuilder_.mergeFrom(value);
      }
      if (negativeExpireTime_ != null) {
        bitField0_ |= 0x00000002;
        onChanged();
      }
      return this;
    }
<pre>
For requested entities that did not match the threat list, how long to
cache the response until.
</pre>

<code>.google.protobuf.Timestamp negative_expire_time = 2;</code>
java-webrisk/proto-google-cloud-webrisk-v1/src/main/java/com/google/webrisk/v1/SearchHashesResponse.java