如何消除Struts中重复的错误提示

原文出处：http://appfuse.547863.n4.nabble.com/duplicated-error-messages-for-struts-framework-td4032183.html

在使用appfuse时，发现Struts的validation框架会重复显示错误信息，查到了一篇文章告诉了解决方案，需要将messages.jsp修改如下：

<% if (request.getAttribute("struts.valueStack") != null) { %>

<%-- ActionError Messages - usually set in Actions --%>

<s:if test="hasActionErrors()">

<div class="error" id="errorMessages">

<s:iterator value="actionErrors">

<img src="<c:url value="/images/iconWarning.gif"/>"

alt="<fmt:message key="icon.warning"/>" class="icon" />

<s:property/><br />

</s:iterator>

</div>

</s:if>

<%-- FieldError Messages - usually set by validation rules --%>

<s:if test="hasFieldErrors()">

<div class="error" id="errorMessages">

<s:iterator value="fieldErrors">

<s:iterator value="value">

<img src="<c:url value="/images/iconWarning.gif"/>"

alt="<fmt:message key="icon.warning"/>" class="icon" />

<s:property/><br />

</s:iterator>

</s:iterator>

</div>

</s:if>

<%-- Success Messages --%>

<c:if test="${not empty messages}">

<div class="message" id="successMessages">

<c:forEach var="msg" items="${messages}">

<img src="<c:url value="/images/iconInformation.gif"/>"

alt="<fmt:message key="icon.information"/>" class="icon" />

<c:out value="${msg}"/><br />

</c:forEach>

</div>

<c:remove var="messages" scope="session"/>

</c:if>

<% } else { %>

<%-- avoid duplicate messages: --%>

<%-- Error Messages (on JSPs, not through Struts --%>

<%-- avoid duplicate messages: --%>

<c:if test="${not empty errors}">

<div class="error" id="errorMessages">

<c:forEach var="error" items="${errors}">

<img src="<c:url value="/images/iconWarning.gif"/>"

alt="<fmt:message key="icon.warning"/>" class="icon" />

<c:out value="${error}"/><br />

</c:forEach>

</div>

<c:remove var="errors" scope="session"/>

</c:if>

<% } %>