当发生错误时，Cloudopt Next将会自动调用错误拦截器进行处理。默认的错误拦截器 DefaultErrorHandler 会拦截 404 和 500 错误并输出错误信息。

    如果您需要处理更多错误，可以模仿 DefaultErrorHandler 创建一个Handler，并在配置文件中修改相应的配置即可。

    1. class DefaultErrorHandler : ErrorHandler() {
    3.     override fun handle(statusCode: Int, throwable: Throwable?) {
    4.         if (abs(errorStatusCode) == 404) {
    5.             response.putHeader(HttpHeaders.CONTENT_TYPE, "text/html;charset=utf-8")
    6.             context.response().end(Welcomer.notFound())
    7.             return
    8.         }
    10.         if (abs(errorStatusCode) == 500) {
    11.             response.putHeader(HttpHeaders.CONTENT_TYPE, "text/html;charset=utf-8")
    12.             context.response().end(Welcomer.systemError())
    13.             return
    14.         }
    15.         val errorMessage = if ((throwable?.message ?: "").isNotBlank()) {
    16.             throwable?.message ?: ""
    17.         } else if (context.data().containsKey("errorMessage")) {
    18.             context.data()["errorMessage"].toString()
    19.         } else {
    20.             "This is a bad http request, please check if the parameters match the requirements."
    21.         }
    22.         renderJson(creatResult(errorStatusCode.toString(), errorMessage))
    23.     }
    25.     private fun creatResult(error: String, errorMessage: String): HashMap<String, String> {
    26.         val map = hashMapOf<String, String>()
    27.         map["error"] = error
    28.         map["errorMessage"] = errorMessage
    29.         return map
    30.     }
    33.     private val errorStatusCode: Int
    34.         get() {
    35.             if (this.context.statusCode() > 0) {
    36.                 this.response.statusCode = this.context.statusCode()
    37.             } else {
    38.                 this.response.statusCode = 500
    39.             }
    40.             return this.response.statusCode
    41.         }
    42. }