java.net.URI.create异常

Question

java.net.URI.create("http://adserver.adtech.de/adlink|3.0")

throws

java.net.URISyntaxException: 
Illegal character in path at index 32: http://adserver.adtech.de/adlink|3.0

although

new java.net.URL("http://adserver.adtech.de/adlink|3.0")

works just fine.

UPDATE 1

although

new org.apache.commons.httpclient.URI("http://adserver.adtech.de/adlink|3.0")

also works perfectly.

What's the reason?

Answer 1

The constructor of URI that takes a single String argument requires that you follow the strict syntax rules that RFC 2396 defines for URIs. According to those rules | should be encoded as %7C . The other constructors can encode the URI components for you, so for example this won't throw an exception:

new java.net.URI("http", "//adserver.adtech.de/adlink|3.0", null);

The URL class on the other does not enforce the URI syntax rules. In fact, it is your responsibility to encode the components that should be encoded; the URL class won't help you. From the documentation :

It is the responsibility of the caller to encode any fields, which need to be escaped prior to calling URL, and also to decode any escaped fields, that are returned from URL.