public Builder setTimestamp(long value) {
            copyOnWrite();
            instance.setTimestamp(value);
            return this;
        }
<code>optional int64 timestamp = 3;</code>

@param value The timestamp to set.
@return This builder for chaining.
turms-client-kotlin/src/main/java/im/turms/client/model/proto/model/user/UserLocation.java