What to do when javax.el.ELException: Not a Valid Method Expression: appears when the JSF screen is displayed

--Environment - Windows10 Pro 64bit - Eclipse Version: Oxygen.3a Release (4.7.3a) -(For project) java version "1.7.0_79" -(For Eclipse) java version "1.8.0_231"

Event: I got angry when I added a button to .xhtml and displayed it.

javax.el.ELException: Not a Valid Method Expression: 
    at com.sun.el.lang.ExpressionBuilder.createMethodExpression(ExpressionBuilder.java:311)
    at com.sun.el.ExpressionFactoryImpl.createMethodExpression(ExpressionFactoryImpl.java:96)
    at org.jboss.weld.util.el.ForwardingExpressionFactory.createMethodExpression(ForwardingExpressionFactory.java:43)
    at org.jboss.weld.el.WeldExpressionFactory.createMethodExpression(WeldExpressionFactory.java:53)
    at com.sun.faces.facelets.tag.TagAttributeImpl.getMethodExpression(TagAttributeImpl.java:240)
...

Cause: You did not specify the action attribute of the button

javax.el.ELException: Not a Valid Method Expression: (JSF forum at Coderanch)

Added button


<h:commandButton action="" value="button" />

Action: Specify the action attribute of the button

Added button


<h:commandButton action="{ponController.go}" value="button" />

Recommended Posts

What to do when javax.el.ELException: Not a Valid Method Expression: appears when the JSF screen is displayed
What to do if Operation not permitted is displayed when you execute a command in the terminal
What to do about the "cannot be read or is not a valid ZIP file" error
What to do when is invalid because it does not start with a'-'
[Rails] What to do when the Refile image is not displayed when writing the processing at the time of Routing Error
What to do when Method not found in f: ajax
What to do if FacesMessage is set but not displayed
What to do when Cannot apply expression operators to method binding
[Ruby / Rails] What to do when NoMethodError appears when using a destructive method such as filter!
What to do when a could not find driver appears when connecting to a DB in a Docker environment
[Ubuntu 20.04] What to do if the external monitor is not recognized
What to do when the changes in the Servlet are not reflected
What to do when you want to know the source position where the method is defined in binding.pry
What to do when a javax.el.PropertyNotWritableException occurs
[IOS] What to do when the image is filled with one color
What to do if the background image is not applied after deployment
What to do if the prefix c is not bound in JSP
When the project is not displayed in eclipse
What to do when you want to delete a migration file that is "NO FILE"
What to do when the value becomes null in the second getSubmittedValue () in JSF Validator
What to do when rails db: seed does not reflect in the database
[Grails] Error occurred running What to do when the Grails CLI does not start
[Swift] What to do if the app icon is set but not reflected
What to do if you get an "A server is already running." Error when you try to start the rails server
What to do when The SSL certificate has expired
What to do when ‘Could not find’ in any of the sources appears in the development environment with Docker × Rails × RSpec
What to do when a null byte error occurs
What to do when rails creates a 〇〇 2.rb file
What to do when Address already in use is displayed after executing rails s
What to do if the breakpoint is shaded and does not stop during debugging
ParseException: What to do when Unparseable date is reached
A warning is displayed when trying to use a huge integer with the special variables $ 1, $ 2, $ 3 ...
[Maven] What to do if you are asked to incorporate a jar that is not in the remote repository into the war
[Joke] What to do when the invalid sample rate is reached when using Mixxx on Ubuntu 20.04
What to do when Cannot format given Object as a Date in convertDateTime of JSF
[Rails Tutorial Chapter 2] What to do when you make a mistake in the column name
What to do when Rails on Docker does not reflect controller changes in the browser
What is the pluck method?
What is a lambda expression?
What is the initialize method?
What to do when "relation" hibernate_sequence "does not exist" in the ID column of PostgreSQL + JPA
[Rails] What to do when the error No database selected and Unknown database appears in db: migrate
[Ruby] What to do when the error "cannot load such file" appears when executing VS Code debug
[Note] What to do if bundle install in Chapter 3 of the rails tutorial is not possible
[Java] What to do if a lot of "File is opened too much" is displayed due to FileNotFoundException
What to do when CSS is not applied in JSF and one or more resources have the target of'head', but no'head' component has been defined within the view.
What to do when an UnsupportedCharsetException occurs in a lightweight JRE
[Rails] What to do if data is not registered in DB
What to do if Cloud9 is full in the Rails tutorial
What to do if the Eclipse Maven dependency Jar is wrong
[Rails] What to do when rails s does not respond or does not stop
What to do when you become a Problem During Content Assist
What to do when you run into a docker-compose node_modules problem
Resultset's next () is not a "method to determine if there is a ResultSet next".
Rails Direct hit prohibition method (Do not transition to another person's edit screen by entering the URL)
What to do if zip dies if there is a pom when making an executable jar with gradle
What is a lambda expression (Java)
What to do when javax.batch.operations.JobStartException occurs
What to do when Blocked Host: "host name" appears in Ruby on Rails
[Java small story] Monitor when a value is added to the List
Notes on what to do when EC2 is set up with t2.micro