apollo-openapi/src/main/java/com/ctrip/framework/apollo/openapi/dto/OpenNamespaceDTO.java/OpenNamespaceDTO/toString
class OpenNamespaceDTO:  @Override
  public String toString() {
    return "OpenNamespaceDTO{" +
        "appId='" + appId + '\'' +
        ", clusterName='" + clusterName + '\'' +
        ", namespaceName='" + namespaceName + '\'' +
        ", comment='" + comment + '\'' +
        ", format='" + format + '\'' +
        ", isPublic=" + isPublic +
        ", items=" + items +
        ", dataChangeCreatedBy='" + dataChangeCreatedBy + '\'' +
        ", dataChangeLastModifiedBy='" + dataChangeLastModifiedBy + '\'' +
        ", dataChangeCreatedTime=" + dataChangeCreatedTime +
        ", dataChangeLastModifiedTime=" + dataChangeLastModifiedTime +
        '}';
  }