hibernate 没有报错 但是没有写入数据

基础的新闻类
@Entity
@Table(name="news")
public class News {
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
private Integer id;
private String title;
private String content;

public Integer getId() {
return id;
}

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

public String getTitle() {
return title;
}

public void setTitle(String title) {
this.title = title;
}

public String getContent() {
return content;
}

public void setContent(String content) {
this.content = content;
}

}
public class NewsManager {
public static void main(String[] args) {
Configuration conf = new Configuration().configure();

SessionFactory sf = conf.buildSessionFactory();

Session sess = sf.openSession();

Transaction tx = sess.beginTransaction();

News n = new News();
n.setTitle("yujunyi");
n.setContent("handsome");
sess.save(n);
sess.close();
sf.close();
}
}配置文件
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
                                         "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory >
  <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
  <property name="hibernate.connection.password">root</property>
  <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernate?useSSL=false</property>
  <property name="hibernate.connection.username">root</property>
  <property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
  <property name="hibernate.show_sql">true</property>
  <property name="hbm2ddl.auto">update</property>
  <property name="hibernate.c3p0.max_size">20</property>
  <property name="hibernate.c3p0.min_size">1</property>
  <property name="hibernate.c3p0.timeout">5000</property>
  <property name="hibernate.c3p0.max_statements">100</property>
  <property name="hibernate.hbm2ddl.auto">update</property>
  <property name="hibernate.c3p0.idle_test_period">3000</property>
  <property name="hibernate.c3p0.acquire_increment">2</property>
  <property name="connection.autocommit">true</property>
  <mapping class="hibernateDemo.News"/>
</session-factory>
</hibernate-configuration>麻烦帮看看 多谢