How to Check Number is Negative?

1
Hi All,   I am checking the user’s age if user is entering his age below 0 i.e. negative then there should be validation. in microflow first i am checking whether age is empty or not if not empty then i am checking whether the age is greater than 0 i wrote code in microflow as below-   $FarmerPersonalDetails/Age > 0   if it is below 0 then i am giving validation but if i directly click on save button without filling the datathen it is giving me some error like below..     An error has occurred while handling the request. [User 'demo_user' with session id '04dd09e0-XXXX-XXXX-XXXX-XXXXXXXXd50e' and roles 'Farmer'] -------- com.mendix.modules.microflowengine.MicroflowException: Failed to evaluate expression, error occurred on line 1, character 1 $FarmerPersonalDetails/Age > 0 ^     at MyFirstModule.ACT_Farmer_Save (Gateway : '') Advanced stacktrace:     at com.mendix.languages.mxexpressions.MxExpressionImpl.evaluate(MxExpressionImpl.scala:32) Caused by: com.mendix.languages.expressions.ExpressionException: Left and right hand side of binary expression should not be empty     at com.mendix.languages.expressions.Expr.evaluate(Expr.scala:16) Caused by: java.lang.IllegalArgumentException: Left and right hand side of binary expression should not be empty     at com.mendix.languages.expressions.BinaryExpr$$anonfun$error$1.applyOrElse(BinaryExpr.scala:50)     at com.mendix.languages.expressions.BinaryExpr$$anonfun$error$1.applyOrElse(BinaryExpr.scala:48)     at scala.runtime.AbstractPartialFunction.apply(AbstractPartialFunction.scala:35)     at com.mendix.languages.expressions.BinaryExpr$$anonfun$compare$1.applyOrElse(BinaryExpr.scala:118)     at com.mendix.languages.expressions.BinaryExpr$$anonfun$compare$1.applyOrElse(BinaryExpr.scala:118)     at com.mendix.languages.expressions.BinaryExpr.evaluateExpression(BinaryExpr.scala:32)     at com.mendix.languages.expressions.Expr.evaluate(Expr.scala:13)     at com.mendix.languages.mxexpressions.MxExpressionImpl.evaluate(MxExpressionImpl.scala:25)     at com.mendix.modules.microflowengine.actions.other.GatewayAction.execute(GatewayAction.scala:37)     at com.mendix.modules.microflowengine.microflow.impl.MicroflowObject.$anonfun$execute$1(MicroflowObject.scala:32)     at scala.Option.flatMap(Option.scala:283)     at com.mendix.modules.microflowengine.microflow.impl.MicroflowObject.execute(MicroflowObject.scala:29)     at com.mendix.modules.microflowengine.microflow.impl.MicroflowImpl.$anonfun$executeAfterBreakingIfNecessary$2(MicroflowImpl.scala:167)     at scala.Option.flatMap(Option.scala:283)     at com.mendix.modules.microflowengine.microflow.impl.MicroflowImpl.executeAfterBreakingIfNecessary(MicroflowImpl.scala:167)     at com.mendix.modules.microflowengine.microflow.impl.MicroflowImpl.executeAction(MicroflowImpl.scala:114)     at com.mendix.systemwideinterfaces.core.UserAction.execute(UserAction.java:58)     at com.mendix.basis.actionmanagement.CoreActionHandlerImpl.doCall(CoreActionHandlerImpl.scala:71)     at com.mendix.basis.actionmanagement.CoreActionHandlerImpl.call(CoreActionHandlerImpl.scala:48)     at com.mendix.core.actionmanagement.internal.InternalCoreAction.call(InternalCoreAction.java:56)     at com.mendix.basis.actionmanagement.ActionManager.$anonfun$executeSync$2(ActionManager.scala:106)     at com.mendix.util.classloading.Runner$.withContextClassLoader(Runner.scala:20)     at com.mendix.basis.actionmanagement.ActionManager.executeSync(ActionManager.scala:105)     at com.mendix.basis.actionmanagement.MicroflowCallBuilderImpl.execute(MicroflowCallBuilderImpl.scala:62)     at com.mendix.webui.actions.client.ExecuteMicroflowAction.runMicroflow(ExecuteMicroflowAction.scala:76)     at com.mendix.webui.actions.client.ExecuteMicroflowAction.$anonfun$apply$3(ExecuteMicroflowAction.scala:42)     at com.mendix.webui.actions.client.RegularClientAction$Helpers$.$anonfun$liftEither$1(RegularClientAction.scala:30)     at com.mendix.webui.actions.client.RegularClientAction$Helpers$StateHandler.$anonfun$apply$4(RegularClientAction.scala:56)     at com.mendix.webui.requesthandling.helpers.StateHandling.withState(StateHandling.scala:42)     at com.mendix.webui.requesthandling.helpers.StateHandling.withState$(StateHandling.scala:39)     at com.mendix.webui.actions.client.RegularClientAction$Helpers$StateHandler.withState(RegularClientAction.scala:46)     at com.mendix.webui.actions.client.RegularClientAction$Helpers$StateHandler.apply(RegularClientAction.scala:54)     at com.mendix.webui.actions.client.RegularClientAction$Helpers$StateHandler.apply(RegularClientAction.scala:46)     at com.mendix.webui.actions.client.ExecuteMicroflowAction.apply(ExecuteMicroflowAction.scala:43)     at com.mendix.webui.actions.client.ExecuteMicroflowAction.apply(ExecuteMicroflowAction.scala:22)     at com.mendix.webui.actions.client.RegularClientAction.$anonfun$execute$3(RegularClientAction.scala:113)     at scala.util.Try$.apply(Try.scala:210)     at com.mendix.webui.actions.client.RegularClientAction.$anonfun$execute$2(RegularClientAction.scala:113)     at com.mendix.webui.actions.client.RegularClientAction.$anonfun$execute$2$adapted(RegularClientAction.scala:111)     at com.mendix.webui.requesthandling.helpers.ContextHandling.$anonfun$inContext$5(ContextHandling.scala:57)     at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.scala:18)     at com.mendix.basis.actionmanagement.ActionMonitoring$.$anonfun$monitor$1(ActionMonitoring.scala:49)     at com.mendix.util.classloading.Runner$.withContextClassLoader(Runner.scala:20)     at com.mendix.basis.actionmanagement.ActionMonitoring$.monitor(ActionMonitoring.scala:49)     at com.mendix.webui.requesthandling.helpers.ContextHandling.inContext(ContextHandling.scala:57)     at com.mendix.webui.requesthandling.helpers.ContextHandling.inContext$(ContextHandling.scala:31)     at com.mendix.webui.actions.client.RegularClientAction.inContext(RegularClientAction.scala:87)     at com.mendix.webui.requesthandling.helpers.ContextHandling.inContext(ContextHandling.scala:28)     at com.mendix.webui.requesthandling.helpers.ContextHandling.inContext$(ContextHandling.scala:20)     at com.mendix.webui.actions.client.RegularClientAction.inContext(RegularClientAction.scala:87)     at com.mendix.webui.actions.client.RegularClientAction.$anonfun$execute$1(RegularClientAction.scala:111)     at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.scala:18)     at com.mendix.webui.requesthandling.helpers.ProfileHandling.profileRequest(ProfileHandling.scala:14)     at com.mendix.webui.requesthandling.helpers.ProfileHandling.profileRequest$(ProfileHandling.scala:10)     at com.mendix.webui.actions.client.RegularClientAction.profileRequest(RegularClientAction.scala:87)     at com.mendix.webui.actions.client.RegularClientAction.execute(RegularClientAction.scala:108)     at com.mendix.webui.requesthandling.ClientRequestHandler.handleAction(ClientRequestHandler.scala:106)     at com.mendix.webui.requesthandling.ClientRequestHandler.processRequest(ClientRequestHandler.scala:79)     at com.mendix.externalinterface.connector.RequestHandler.doProcessRequest(RequestHandler.java:37)     at com.mendix.external.connector.MxRuntimeConnector.$anonfun$processRequest$1(MxRuntimeConnector.scala:50)     at com.mendix.external.connector.MxRuntimeConnector.$anonfun$processRequest$1$adapted(MxRuntimeConnector.scala:50)     at com.mendix.util.classloading.Runner$.withContextClassLoader(Runner.scala:20)     at com.mendix.external.connector.MxRuntimeConnector.processRequest(MxRuntimeConnector.scala:50)     at com.mendix.basis.impl.MxRuntimeImpl.processRequest(MxRuntimeImpl.scala:223)     at com.mendix.m2ee.appcontainer.server.handler.RuntimeServlet.service(RuntimeServlet.scala:25)     at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)     at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:799)     at org.eclipse.jetty.servlet.ServletHandler$ChainEnd.doFilter(ServletHandler.java:1631)     at org.eclipse.jetty.websocket.server.WebSocketUpgradeFilter.doFilter(WebSocketUpgradeFilter.java:230)     at org.eclipse.jetty.servlet.FilterHolder.doFilter(FilterHolder.java:193)     at org.eclipse.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1601)     at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:548)     at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233)     at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1624)     at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233)     at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1440)     at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:188)     at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:501)     at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1594)     at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:186)     at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1355)     at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)     at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127)     at org.eclipse.jetty.server.Server.handle(Server.java:516)     at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(HttpChannel.java:487)     at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:732)     at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:479)     at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:277)     at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311)     at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:105)     at org.eclipse.jetty.io.ChannelEndPoint$1.run(ChannelEndPoint.java:104)     at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:338)     at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:315)     at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:173)     at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:131)     at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:409)     at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:883)     at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1034)     at java.base/java.lang.Thread.run(Thread.java:834)  
asked
2 answers
0

Hi 

Whenever we tried to write expressions, both the left and right sides should not have empty values. 

Here your age seems empty, which is why you are getting this error.

answered
0

Hi prajakta,

Actually the value(age) you are cheking is actually empty. Thats why this error is coming. 

You xan correct this by adding one more expression in the decision where you are checking the negative number..

Add it..

$FarmerPersonalDetails/Age !=0 and $FarmerPersonalDetails/Age > 0

 

It will work.

 

Hope it helps!

 

 

 

answered