javax.servlet.ServletException: java.lang.LinkageError: loader constraint violation: when resolving interface method "javax.servlet.jsp.JspApplicationContext.getExpressionFactory()Ljavax/el/ExpressionFactory;" 
the class loader (instance of org/apache/jasper/servlet/JasperLoader) of the current class, org/apache/jsp/WEB_002dINF/views/success_jsp, and the class loader (instance of org/codehaus/plexus/classworlds/realm/ClassRealm) 
for the method's defining class, javax/servlet/jsp/JspApplicationContext, have different Class objects for the type javax/el/ExpressionFactory used in the signature

    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:)

    javax.servlet.http.HttpServlet.service(HttpServlet.java:)

    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:)

    org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:)

    org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:)

    org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:)

    org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:)

    org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:)

    org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:)

    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:)

    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:)

    javax.servlet.http.HttpServlet.service(HttpServlet.java:)

    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:)

    javax.servlet.http.HttpServlet.service(HttpServlet.java:)

    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:)

    org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:)

    org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:)

    org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:)

    org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:)

Tomcat 包下的 javax.el-api 与 用于验证的 Hibernate-validation 包下的 javax.el-api 冲突。

<dependency>

    <groupId>org.hibernate</groupId>

    <artifactId>hibernate-validator</artifactId>

    <version>5.0..CR2</version>

    <exclusions>

        <exclusion>

            <groupId>javax.el</groupId>

            <artifactId>javax.el-api</artifactId>

        </exclusion>

    </exclusions>

</dependency>