问题描述
我试图提取网页的内容A.使用groovy我试过以下内容:
I am trying to extract the content of a webpage A. Using groovy I've tried the following
......
String urlStr = "url-of-webpage-A"
String pageText = urlStr.toURL().text
//println pageText
.....
只要不重定向到其他网页,上述代码就会检索网页A的文字B.如果A重定向到B,则在pageText变量中检索webPage B的页面内容。有没有一种方法来编写和检查webPage A是否重定向到其他网页(在groovy或java中)?
The above code retrieves the text of webPage A as long as it doesn't redirect to an other webpage B. If A redirects to B, the page content of webPage B is retrieved in the pageText variable. Is there a way to code and check if webPage A is redirecting to an other webpage (in groovy or java)?
PS:上面的代码段不是一部分的服务器端逻辑。我在桌面应用程序的范围内在客户端执行它。
PS: The above piece of code is not a part of server side logic. I am executing it on the client side within the scope of a desktop appilcation.
推荐答案
在groovy中,您可以执行在做:
In groovy, you could do what Joachim suggests by doing:
String location = "url-of-webpage-A"
boolean wasRedirected = false
String pageContent = null
while( location ) {
new URL( location ).openConnection().with { con ->
// We'll do redirects ourselves
con.instanceFollowRedirects = false
// Get the response code, and the location to jump to (in case of a redirect)
location = con.getHeaderField( "Location" )
if( !wasRedirected && location ) {
wasRedirected = true
}
// Read the HTML and close the inputstream
pageContent = con.inputStream.withReader { it.text }
}
}
println "wasRedirected:$wasRedirected contentLength:${pageContent.length()}"
如果您不想被重定向,并且希望第一页的内容,你只需要做:
If you don't want to be redirected, and want the contents of the first page, you simply need to do:
String location = "url-of-webpage-A"
String pageContent = new URL( location ).openConnection().with { con ->
// We'll do redirects ourselves
con.instanceFollowRedirects = false
// Get the location to jump to (in case of a redirect)
location = con.getHeaderField( "Location" )
// Read the HTML and close the inputstream
con.inputStream.withReader { it.text }
}
if( location ) {
println "Page wanted to redirect to $location"
}
println "Content was:"
println pageContent
这篇关于如何检查页面的url是否重定向?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!