JSF: How validate fields and return error messages by bean validation?

I have a contact form and I have some fields that are validated by bean validation, how could I return bean validation error messages after submitting?

For example:

<h:form>
    <h:inputText id="name" value="#{contact.client.name}"></h:inputText>Name (Required)
    <h:inputText id="email" value="#{contact.client.email}"></h:inputText>E-Mail (Required)
    <h:inputText id="website" value="#{contact.client.website}"></h:inputText>Website (Optional)
    <h:inputText id="text" value="#{contact.client.text}"></h:inputText>Message (Required):

    <h:commandButton value="Send" action="#{contact.sendMessage}" >
        <f:ajax execute="@form" render="@form"/>
    </h:commandButton>

</h:form>

This is how I'm validating my fields:

        // Client.java (model)
    @NotNull(message="Please provide your name")
    private String name;

    @NotNull(message="Please provide your email")
    @Pattern(regexp = "([^.@]+)(\\.[^.@]+)*@([^.@]+\\.)+([^.@]+)", message = "Invalid e-mail")
    private String email;

    @Pattern(regexp = "(http[s]?://|ftp://)?(www\\.)?[a-zA-Z0-9-\\.]+\\.([a-zA-Z]{2,5})$", message = "Not valid URL")
    private String website;

    @NotNull(message="Please provide your message")
    private String text;

Either use <h:message> which you attach to specific components by for attribute which should refer the id of the input component:

<h:inputText id="name" value="#{contact.client.name}"></h:inputText>Name (Required)
<h:message for="name" />
<h:inputText id="email" value="#{contact.client.email}"></h:inputText>E-Mail (Required)
<h:message for="email" />
<h:inputText id="website" value="#{contact.client.website}"></h:inputText>Website (Optional)
<h:message for="website" />
<h:inputText id="text" value="#{contact.client.text}"></h:inputText>Message (Required):
<h:message for="text" />

or use <h:messages/> to display them all at a single place:

<h:messages />

Yes, bean validation messages also ends in there.

Don't forget to ensure that the button's render attribute covers them as well.

JSF: How validate fields and return error messages by bean validation?

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