FreeMarker template error!<![CDATA[
Expression prev_id is undefined on line 64, column 6 in tpl/2015/c/www.cleanoil.com.hk/wap/displaynews.html.
The problematic instruction:
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==> if-else [on line 64, column 1 in tpl/2015/c/www.cleanoil.com.hk/wap/displaynews.html]
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Java backtrace for programmers:
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freemarker.core.InvalidReferenceException: Expression prev_id is undefined on line 64, column 6 in tpl/2015/c/www.cleanoil.com.hk/wap/displaynews.html.
at freemarker.core.TemplateObject.assertNonNull(TemplateObject.java:124)
at freemarker.core.ComparisonExpression.isTrue(ComparisonExpression.java:121)
at freemarker.core.IfBlock.accept(IfBlock.java:80)
at freemarker.core.Environment.visit(Environment.java:245)
at freemarker.core.MixedContent.accept(MixedContent.java:92)
at freemarker.core.Environment.visit(Environment.java:245)
at freemarker.core.Environment.process(Environment.java:225)
at freemarker.template.Template.process(Template.java:241)
at freemarker.ext.servlet.FreemarkerServlet.process(FreemarkerServlet.java:310)
at freemarker.ext.servlet.FreemarkerServlet.doGet(FreemarkerServlet.java:245)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:114)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:91)
at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:103)
at shield.front.action.filter.NotAllowedToTunFilesFilter.doFilter(NotAllowedToTunFilesFilter.java:127)
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)
at shield.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:81)
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)
at shield.front.action.filter.InvalidXSSFilter.doFilter(InvalidXSSFilter.java:93)
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)
at com.caucho.filters.GzipFilter.doFilter(GzipFilter.java:151)
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)
at com.caucho.server.cache.CacheFilterChain.doFilter(CacheFilterChain.java:192)
at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:187)
at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:265)
at com.caucho.server.hmux.HmuxRequest.handleRequest(HmuxRequest.java:436)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:682)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
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