Cannot find declaration of element handler-chains Jboss Developer Studio
I resolved the issue by replacing
<handler-chains xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsd="http://www.w3.org/2001/XMLSchema">to
<handler-chains xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/javaee_web_services_metadata_handler_2_0.xsd">
I had a similar problem in Eclipse + JDK 1.8 that was resolved by changing the address of the XMLNS attribute.
From:
<javaee:handler-chains xmlns:javaee="http://java.sun.com/xml/ns/javaee" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
To:
<javaee:handler-chains xmlns:javaee="http://xmlns.jcp.org/xml/ns/javaee/" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
See the link below that Oracle has changed the address of the new schemas:http://www.oracle.com/webfolder/technetwork/jsc/xml/ns/javaee/index.html#7