The implementation of BeanValidation is not working

Greeting for all,

Please note the XHTML page;

<ui:composition template="/WEB-INF/template/LayoutSystem.xhtml"
    xmlns="http://www.w3.org/1999/xhtml"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:p="http://primefaces.org/ui">

    <ui:define name="titulo">Novas Notícias</ui:define>

    <ui:define name="corpo">
        <h:form>
            <h1>Novas Notícias</h1>

            <p:messages autoUpdate="true" closable="true" />

            <p:toolbar style="margin-top: 20px">
                <p:toolbarGroup>
                    <p:button value="Novo" />
                    <p:commandButton value="Salvar" id="botaoSalvar"
                        action="#{cadastroNoticiaBean.salvar}" />
                </p:toolbarGroup>
                <p:toolbarGroup align="right">
                    <p:button value="Pesquisa"
                        outcome="/noticias/PesquisaNoticias.xhtml" />
                </p:toolbarGroup>
            </p:toolbar>

            <div id="wrap">

                <div class="left-sidebar">
                    <p:panelGrid columns="2" id="painel1"
                        style="width: 50%; margin-top: 20px" columnClasses="rotulo, campo">

                        <p:outputLabel value="Titulo" for="titulo" />
                        <p:inputText id="titulo" size="20" maxlength="20"
                        value="#{cadastroNoticiaBean.noticia.titulo_noticia}" />

                        <p:outputLabel value="Data" for="data" />
                        <p:inputText id="data" size="20" maxlength="20" />
                        <p:outputLabel value="#{cadastroNoticiaBean.noticia.data_noticia}" />
                        <h:panelGroup>

                            <p:fileUpload mode="simple" skinSimple="true" />

                            <p:commandButton value="Submit" ajax="false" disabled="true" />
                        </h:panelGroup>

                        <p:outputLabel value="Descrição" for="descricao" />
                        <p:inputText id="descricao" size="20" maxlength="20" 
                        value="#{cadastroNoticiaBean.noticia.desc_noticia}"/>
                    </p:panelGrid>

                </div>





            </div>



        </h:form>
    </ui:define>
</ui:composition>

I'm building a project in Maven and include the BeanValidation library as you can see;

<!-- Implementacao do Bean Validation -->
<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-validator</artifactId>
    <version>5.0.1.Final</version>
    <scope>compile</scope>
</dependency>

Here's the Bean class.

package br.com.vendelancha.controller;

import java.io.Serializable;

import javax.faces.bean.ViewScoped;
import javax.inject.Named;

import br.com.vendelancha.model.Noticia;

@Named
@ViewScoped
public class CadastroNoticiaBean implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    private Noticia noticia;

    public CadastroNoticiaBean() {
        noticia = new Noticia();
    }

    public void salvar() {
    }

    public Noticia getNoticia() {
        return noticia;
    }

}

Attention would be to test the save button to see if the validations are working, but nothing happens, see how my entity is;

package br.com.vendelancha.model;

import java.io.Serializable;
import java.util.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import javax.validation.constraints.NotNull;

@Entity
public class Noticia implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    private Long id;
    private String titulo_noticia;
    private Date data_noticia;
    private String foto_noticia;
    private String desc_noticia;

    @Id
    @GeneratedValue
    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    @NotNull
    @Column(nullable = false, length = 100)
    public String getTitulo_noticia() {
        return titulo_noticia;
    }

    public void setTitulo_noticia(String titulo_noticia) {
        this.titulo_noticia = titulo_noticia;
    }

    @NotNull
    @Temporal(TemporalType.TIMESTAMP)
    @Column(nullable = false)
    public Date getData_noticia() {
        return data_noticia;
    }

    public void setData_noticia(Date data_noticia) {
        this.data_noticia = data_noticia;
    }

    public String getFoto_noticia() {
        return foto_noticia;
    }

    public void setFoto_noticia(String foto_noticia) {
        this.foto_noticia = foto_noticia;
    }

    @Column(columnDefinition = "text")
    public String getDesc_noticia() {
        return desc_noticia;
    }

    public void setDesc_noticia(String desc_noticia) {
        this.desc_noticia = desc_noticia;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((id == null) ? 0 : id.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        Noticia other = (Noticia) obj;
        if (id == null) {
            if (other.id != null)
                return false;
        } else if (!id.equals(other.id))
            return false;
        return true;
    }

}