JSF - h:messages

The h:messages tag shows all the messages at one place corresponding to UI elements.

JSF Tag

<h:messages style = "color:red;margin:8px;" />

Rendered Output

Case: Username entered is more than 20 characters and password entered is less than 5 characters.

<ul style = "color:red;margin:8px;"> 
   <li> UserName: Validation Error:  
      Length is greater than allowable maximum of '20' </li> 
   <li> Password: Validation Error:  
      Length is less than allowable minimum of '5' </li> 
</ul>

Tag Attributes

S.No	Attribute & Description
1	id Identifier for a component
2	binding Reference to the component that can be used in a backing bean
3	rendered A boolean; false suppresses rendering
4	styleClass Cascading stylesheet (CSS) class name
5	for The ID of the component whose message is displayed, applicable only to h:message
6	errorClass CSS class applied to error messages
7	errorStyle CSS style applied to error messages
8	fatalClass CSS class applied to fatal messages
9	fatalStyle CSS style applied to fatal messages
10	globalOnly Instruction to display only global messages, applicable only to h:messages. Default: false
11	infoClass CSS class applied to information messages
12	infoStyle CSS style applied to information messages
13	layout Specification for message layout: table or list, applicable only to h:messages
14	showDetail A boolean that determines whether message details are shown. Defaults are false for h:messages, true for h:message
15	showSummary A boolean that determines whether message summaries are shown. Defaults are true for h:messages, false for h:message
16	tooltip A boolean that determines whether message details are rendered in a tooltip; the tooltip is only rendered if showDetail and showSummary are true
17	warnClass CSS class for warning messages
18	warnStyle CSS style for warning messages
19	style Inline style information
20	title A title, used for accessibility, that describes an element. Visual browsers typically create tooltips for the title’s value

Example Application

Let us create a test JSF application to test the above tag.

Step	Description
1	Create a project with a name helloworld under a package com.tutorialspoint.test as explained in the JSF - First Application chapter.
2	Modify home.xhtml as explained below. Keep rest of the files unchanged.
3	Compile and run the application to make sure business logic is working as per the requirements.
4	Finally, build the application in the form of war file and deploy it in Apache Tomcat Webserver.
5	Launch your web application using appropriate URL as explained below in the last step.

home.xhtml

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
   "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 

<html xmlns = "http://www.w3.org/1999/xhtml"> 
   <head> 
      <title>JSF Tutorial!</title> 
   </head>
   
   <body> 
      <h2>h:messages example</h2> 
      <hr /> 
      
      <h:form> 
         <h:panelGrid id = "panel" columns = "2" border = "0" cellpadding = "10"  
         cellspacing = "1">   
            <h:outputLabel value = "Enter Username" /> 
            
            <h:inputText  id = "username"  size = "20" label = "UserName"  
               required = "true"> 
               <f:validateLength for = "username" minimum = "5" maximum = "20" />    
            </h:inputText>         
            <h:outputLabel value = "Enter Password" /> 
            
            <h:inputSecret id = "password" size = "20" label = "Password"  
               required = "true" redisplay = "true" > 
               <f:validateLength for = "password" minimum = "5" maximum = "10" />  
            </h:inputSecret>         
            <h:commandButton id = "submit" value = "Submit" action = "result"/> 
         </h:panelGrid> 
         <h:messages style = "color:red;margin:8px;" /> 
      </h:form> 
   
   </body> 
</html>

Once you are ready with all the changes done, let us compile and run the application as we did in JSF - First Application chapter. If everything is fine with your application, this will produce following result:

jsf_basic_tags.htm