src/main/java/grpc/gateway/protoc_gen_swagger/options/Openapiv2.java
public Builder clearRef() {
        
        ref_ = getDefaultInstance().getRef();
        onChanged();
        return this;
      }
/**
       * <pre>
       * Ref is used to define an external reference to include in the message.
       * This could be a fully qualified proto message reference, and that type must
       * be imported into the protofile. If no message is identified, the Ref will
       * be used verbatim in the output.
       * For example:
       *  `ref: ".google.protobuf.Timestamp"`.
       * </pre>
       *
       * <code>string ref = 3;</code>
       * @return This builder for chaining.
       */

Ref is used to define an external reference to include in the message.
This could be a fully qualified proto message reference, and that type must
be imported into the protofile. If no message is identified, the Ref will
be used verbatim in the output.

string ref = 3;
@return This builder for chaining.
Ref is used to define an external reference to include in the message . This could be a fully qualified proto message reference and that type must be imported into the protofile . If no message is identified the Ref will be used verbatim in the output . string ref = 3 ; @return This builder for chaining .
public Builder clearRef() {
        ref_ = getDefaultInstance().getRef();
        onChanged();
        return this;
      }
public Builder clearRef ( ) { ref_ = getDefaultInstance ( ) . getRef ( ) ; onChanged ( ) ; return this ; }
<pre>
 Ref is used to define an external reference to include in the message.
<pre > Ref is used to define an external reference to include in the message .