xml - 用grails解析XML的问题

Question

我正在开发一个应用程序，该应用程序从Last.fm API中提取有关音乐事件的信息。
但是，由于某种原因，该应用程序仅解析XML文件中的前两个事件，我无法弄清原因。有什么帮助吗？

这是代码:

def resultList = []

    if(connection.responseCode == 200){
        def xml = connection.content.text
        def lfm = new XmlSlurper().parseText(xml)
        lfm.events.event.each {
            def result = [:]
            result.eventId = it.id as String
            result.eventTitle = lfm.events.event.find { it.'id' == result.eventId }.title as String

            resultList << result

        }

Answer 1

我只是发现该错误位于Controller类的save {}闭包中。以下是带有该错误的代码:

def save = {
    resultsList.each{
        def eventInstance = new Event(params + it)
        if (eventInstance.save(flush: true)) {
            flash.message = "${message(code: 'default.created.message', args: [message(code: 'event.label', default: 'Event'), eventInstance.id])}"
            redirect(action: "show", id: eventInstanceID)
        }
        else {
            render(view: "create", model: [eventInstance: eventInstance])
        }
    }
}

因此，问题在于我正在重定向每个{}闭包内的 Action “显示”。由于某种原因，我仍然不确定，它在each {}循环的第二次迭代后引发了异常。因此，我要做的就是在each {}闭包之外调用redirect方法，如下所示:

   def save = {
    def resultsList = eventService.lastFmVenues(params.artist)
    def eventInstanceID
    resultsList.each{
        def eventInstance = new Event(params + it)
        if (eventInstance.save(flush: true)) {
            flash.message = "${message(code: 'default.created.message', args: [message(code: 'event.label', default: 'Event'), eventInstance.id])}"
            eventInstanceID = eventInstance.id
        }
        else {
            render(view: "create", model: [eventInstance: eventInstance])
        }
    }
    redirect(action: "show", id: eventInstanceID)
}

我仍然很好奇为什么仅在第二次迭代后才引发异常，但是无论如何，问题都得到了解决。谢谢!