apollo-openapi/src/main/java/com/ctrip/framework/apollo/openapi/dto/OpenItemDTO.java/OpenItemDTO/toString
class OpenItemDTO:  @Override
  public String toString() {
    return "OpenItemDTO{" +
        "key='" + key + '\'' +
        ", value='" + value + '\'' +
        ", comment='" + comment + '\'' +
        ", dataChangeCreatedBy='" + dataChangeCreatedBy + '\'' +
        ", dataChangeLastModifiedBy='" + dataChangeLastModifiedBy + '\'' +
        ", dataChangeCreatedTime=" + dataChangeCreatedTime +
        ", dataChangeLastModifiedTime=" + dataChangeLastModifiedTime +
        '}';
  }