public Builder setLoginUrlBytes(com.google.protobuf.ByteString value) {
          if (value == null) {
            throw new NullPointerException();
          }
          checkByteStringIsUtf8(value);
          loginUrl_ = value;
          bitField0_ |= 0x00000004;
          onChanged();
          return this;
        }
<pre>
Required. The login form URL of the website.
</pre>

<code>string login_url = 3 [(.google.api.field_behavior) = REQUIRED];</code>

@param value The bytes for loginUrl to set.
@return This builder for chaining.
java-websecurityscanner/proto-google-cloud-websecurityscanner-v1beta/src/main/java/com/google/cloud/websecurityscanner/v1beta/ScanConfig.java