javax.el.ELException: Cannot convert [ +data.resultList[i].catid+ ] of type [class java.lang.String]_javax.el.elexception connot convert string to date-优快云博客

本文链接：https://blog.youkuaiyun.com/xiaobai_ly/article/details/81744574

本文探讨了在Java环境中，由于catid字段从短整型到长整型转换不当导致的ELException异常。通过分析错误堆栈，明确了问题根源在于JSP页面中对数据类型的不当处理。文章提供了详细的错误信息及代码行定位，便于读者理解并解决类似问题。

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求大神解答，catid在后台是短整型的数据类型

javax.el.ELException: Cannot convert [ +data.resultList[i].catid+ ] of type [class java.lang.String] to [class java.lang.Long]
   at org.apache.el.lang.ELSupport.coerceToNumber(ELSupport.java:400)
   at org.apache.el.lang.ELSupport.coerceToNumber(ELSupport.java:379)
   at org.apache.el.lang.ELSupport.equals(ELSupport.java:172)
   at org.apache.el.parser.AstEqual.getValue(AstEqual.java:39)
   at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:190)
   at org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:944)
   at org.apache.jsp.WEB_002dINF.view.news_jsp._jspx_meth_c_005fif_005f1(news_jsp.java:474)
   at org.apache.jsp.WEB_002dINF.view.news_jsp._jspx_meth_c_005fforEach_005f2(news_jsp.java:438)
   at org.apache.jsp.WEB_002dINF.view.news_jsp._jspService(news_jsp.java:242)
   at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
   at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
   at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:443)
   ... 49 more
2018-08-16 16:34:39,232 [http-nio-8080-exec-3] DEBUG [org.springframework.web.servlet.DispatcherServlet] - Could not complete request
org.apache.jasper.JasperException: An exception occurred processing JSP page [/WEB-INF/view/news.jsp] at line [109]

106: alert(data.resultList[i].title);
107: str += '<li><a href="article.jsp"><img src="images/img.jpg">${'+(data.resultList[i].title) +'}';
108: str += '<c:forEach items="${wdjmCategoryList }" var="category">';
109: str += '<c:if test="${' +data.resultList[i].catid+ 'eq category.catid}">';
110: str += '${category.catname }';
111: str += '</c:if></c:forEach>'
112: str += '${' +(data.resultList[i].inputtime)+ '}</a></li>';