hibernate auto increment id MySql using mapping file -

i running simple hibernate application using eclipse indigo,hibernate 3.6.4 , mysql 5.1.36. new hibernate.so please me.

following code shows inserting data

public void adduserdetails(string username, string password, string email,             string phone, string city) {         try {             // 1. configuring hibernate             configuration configuration = new configuration().configure();              // 2. create sessionfactory             sessionfactory sessionfactory = configuration.buildsessionfactory();              // 3. session object             session session = sessionfactory.opensession();              // 4. starting transaction             transaction transaction = session.begintransaction();             user user = new user();             user.setusername(username);             user.setpassword1(password);             user.setemail(email);             user.setcity(city);             user.setphone(phone);             session.save(user);             transaction.commit();             system.out.println("\n\n details added \n");          } catch (hibernateexception e) {             system.out.println(e.getmessage());             system.out.println("error");         }      } } 

by using this,data inserted every time replace data in 1st row.

following code shows mapping file database columns , variables.

<?xml version="1.0" encoding="utf-8"?> <!doctype hibernate-mapping public "-//hibernate/hibernate mapping dtd  3.0//en" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping>     <class name="com.milind.dto.user" table="user">         <id column="id" name="id" type="integer">         <generator class="increment"/>         </id>          <property column="user_name" name="username"  type="java.lang.string" />          <property column="password" name="password1" type="string" />         <property column="email" name="email" type="java.lang.string" />         <property column="phone" name="phone" type="java.lang.string" />         <property column="city" name="city" type="java.lang.string" />     </class> </hibernate-mapping> 

in mysql shows id column auto increment increment not happening.

after running application shows

following in consol

jul 22, 2015 8:58:23 pm org.apache.catalina.core.standardcontext reload info: reloading context name [/test] has started jul 22, 2015 8:58:23 pm org.apache.catalina.loader.webappclassloader    clearreferencesjdbc severe: web application [/test] registered jdbc driver    [com.mysql.jdbc.driver] failed unregister when web application  stopped. prevent memory leak, jdbc driver has been forcibly  unregistered. jul 22, 2015 8:58:23 pm org.apache.catalina.loader.webappclassloader   clearreferencesthreads severe: web application [/test] appears have started thread named   [abandoned connection cleanup thread] has failed stop it. create memory leak. jul 22, 2015 8:58:23 pm org.apache.catalina.startup.tldconfig execute info: @ least 1 jar scanned tlds yet contained no tlds. enable   debug logging logger complete list of jars scanned   no tlds found in them. skipping unneeded jars during scanning can improve   startup time , jsp compilation time. jul 22, 2015 8:58:23 pm org.apache.catalina.core.standardcontext reload  info: reloading context name [/test] completed slf4j: failed load class "org.slf4j.impl.staticloggerbinder". slf4j: defaulting no-operation (nop) logger implementation slf4j: see http://www.slf4j.org/codes.html#staticloggerbinder further   details. hibernate:      select         max(id)              user hibernate:      insert               user         (user_name, password, email, phone, city, id)      values         (?, ?, ?, ?, ?, ?)     details added  

here hibernate.cfg.xml

<?xml version='1.0' encoding='utf-8'?> <!-- ~ hibernate, relational persistence idiomatic java ~ ~ copyright      (c) 2010, red hat inc. or third-party contributors ~ indicated      @author tags or express copyright attribution ~ statements applied      authors. third-party contributions ~ distributed under license      red hat inc. ~ ~ copyrighted material made available  wishing      use, modify, ~ copy, or redistribute subject terms ,  conditions      of gnu ~ lesser general public license, published free software  foundation. ~ ~ program distributed in hope useful,  ~ without warranty; without implied warranty of merchantability  ~ or fitness particular purpose. see gnu lesser general public  license ~ more details. ~ ~ should have received copy of gnu  lesser general public license ~ along distribution; if not, write  to: ~ free software foundation, inc. ~ 51 franklin street, fifth floor ~  boston, ma 02110-1301 usa -->   <?xml version='1.0' encoding='utf-8'?>   <!doctype hibernate-configuration public   "-//hibernate/hibernate configuration dtd//en"   "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">  <hibernate-configuration>     <session-factory>         <property   name="hibernate.dialect">org.hibernate.dialect.mysqldialect</property>     <property name="hibernate.connection.driver_class">com.mysql.jdbc.driver</property>      <property name="hibernate.connection.url">jdbc:mysql://localhost:3535/students</property>      <property name="hibernate.connection.username">root</property>     <property name="hibernate.connection.password">qwera</property>      <property name="hibernate.connection.autocommit">true</property>     <!-- enable hibernate's automatic session context management -->     <property name="current_session_context_class">thread</property>      <!-- disable second-level cache -->     <property name="cache.provider_class">org.hibernate.cache.nocacheprovider</property>      <property name="show_sql">true</property>      <!-- mapping files -->     <mapping class="com.milind.hibernate.dto.userdetails" />   </session-factory> </hibernate-configuration> 

thank you.