JSF <h:messages> Tag

It is used to displays all messages that were stored in the faces context during the course of the JSF life cycle.

Example:

// index.xhtml

<h:form id="form">
<h:outputLabel for="username">User Name</h:outputLabel>
<h:inputText id="name-id" value="#{user.name}"/><br/>
<h:outputLabel for="mobile">Mobile No.</h:outputLabel>
<h:inputText id="mobile-id" value="#{user.mobile}"/><br/>
<h:commandButton value="OK" action="response.xhtml"></h:commandButton>
<!-- Here, we are single tag to display all the errors. -->
<h:messages style="color: red"></h:messages>
</h:form>

// User.java

import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
@ManagedBean
@RequestScoped
public class User{
@NotNull(message = "Name can't be empty")
String name;
@NotNull(message = "Mobile can't be empty")
@Size(min = 10, max = 10, message = "Mobile must have 10 digits")
String mobile;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getMobile() {
return mobile;
}
public void setMobile(String mobile) {
this.mobile = mobile;
}
}

Output