Can't compare values of these types. Allowed comparisons are between two numbers, two strings, two dates, or two booleans.
Left hand operand is a number (wrapper: f.t.SimpleNumber).
Right hand operand is a string (wrapper: f.t.SimpleScalar).
The blamed expression:
==> tab_index="0"  [in template "tpl/2017/06/05/2210117470880064//wap/displayproduct.html" at line 139, column 85]

----
FTL stack trace ("~" means nesting-related):
	- Failed at: #if tab_index = "0"  [in template "tpl/2017/06/05/2210117470880064//wap/displayproduct.html" at line 139, column 79]
----

Java stack trace (for programmers):
----
freemarker.core._MiscTemplateException: [... Exception message was already printed; see it above ...]
	at freemarker.core.EvalUtil.compare(EvalUtil.java:301)
	at freemarker.core.EvalUtil.compare(EvalUtil.java:113)
	at freemarker.core.ComparisonExpression.evalToBoolean(ComparisonExpression.java:62)
	at freemarker.core.ConditionalBlock.accept(ConditionalBlock.java:48)
	at freemarker.core.Environment.visit(Environment.java:327)
	at freemarker.core.Environment.visit(Environment.java:369)
	at freemarker.core.IteratorBlock$IterationContext.executedNestedContentForCollOrSeqListing(IteratorBlock.java:316)
	at freemarker.core.IteratorBlock$IterationContext.executeNestedContent(IteratorBlock.java:272)
	at freemarker.core.IteratorBlock$IterationContext.accept(IteratorBlock.java:243)
	at freemarker.core.Environment.visitIteratorBlock(Environment.java:596)
	at freemarker.core.IteratorBlock.acceptWithResult(IteratorBlock.java:108)
	at freemarker.core.IteratorBlock.accept(IteratorBlock.java:94)
	at freemarker.core.Environment.visit(Environment.java:327)
	at freemarker.core.Environment.visit(Environment.java:333)
	at freemarker.core.Environment.visit(Environment.java:333)
	at freemarker.core.Environment.visit(Environment.java:333)
	at freemarker.core.Environment.visit(Environment.java:333)
	at freemarker.core.Environment.process(Environment.java:306)
	at freemarker.ext.servlet.FreemarkerServlet.processEnvironment(FreemarkerServlet.java:946)
	at freemarker.ext.servlet.FreemarkerServlet.process(FreemarkerServlet.java:910)
	at freemarker.ext.servlet.FreemarkerServlet.doGet(FreemarkerServlet.java:769)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at com.kenfor.iyong.web.util.filter.NotAllowedToTunFilesFilter.doFilter(NotAllowedToTunFilesFilter.java:154)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at com.kenfor.iyong.web.util.filter.InvalidXSSFilter.doFilter(InvalidXSSFilter.java:40)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
	at com.orangefunction.tomcat.redissessions.RedisSessionHandlerValve.invoke(RedisSessionHandlerValve.java:26)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
	at org.apache.coyote.ajp.AbstractAjpProcessor.process(AbstractAjpProcessor.java:873)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:687)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:745)