Displaying the Greeting Message based on Time in MySQL

Hi, My requirement is based on Current time i want to display Greeting message.

For example, if time is less than 12PM then i need to display "Morning" and if time is less than 5PM then i need to display "Afternoon" and if time is above 5 PM i need to display "Evening".

Step1: Selecting the Current time.

SELECT now() from DUAL;

Output:

 '2014-12-28 17:35:46'

Step2: In the Current time getting the hours.

SELECT TIME_FORMAT(now(),'%H') from DUAL;

Output: 

17

Step3: Now based on hours we need to display greeting message. So we need to use if condition.

SELECT IF((SELECT TIME_FORMAT(now(),'%H') from DUAL) < 12,'Morning', IF((SELECT TIME_FORMAT(now(), 
'%H') from DUAL) < 17,'Afternoon','Evening'));

Output:

'Evening'

Happy coding!

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How to get all table names using Hibernate.

This post demonstrates the how to get the all table names using Hibernate.

Configuration configuration = new Configuration();
configuration.configure("hibernate.cfg.xml");
SessionFactory sessionFactory = configuration.buildSessionFactory();

// Way1 - get the all Class Mapping Information using Configuration
Iterator<PersistentClass> classMappings = configuration.getClassMappings();
while(classMappings.hasNext()) {
    PersistentClass persistentClass = classMappings.next();
    Table table = persistentClass.getTable();
    String tableName = table.getName();
    System.out.println(tableName);
}

// Way2 - get the all Class Metadata Information using SessionFactory
Map<String, ClassMetadata> classMetaDataMap = sessionFactory.getAllClassMetadata();
for(Map.Entry<String, ClassMetadata> metaDataMap : classMetaDataMap.entrySet()) {
    ClassMetadata classMetadata = metaDataMap.getValue();
    AbstractEntityPersister abstractEntityPersister = (AbstractEntityPersister) classMetadata;
    String tableName = abstractEntityPersister.getTableName();
    System.out.println(tableName);
}

// Way3 - using Session 
SessionImpl sessionImpl = (SessionImpl) sessionFactory.openSession();
try {
    Connection connection = sessionImpl.connection();
    DatabaseMetaData databaseMetaData = connection.getMetaData();
    ResultSet resultSet = databaseMetaData.getTables(null, null, null, new String[] {"TABLE"});
    while(resultSet.next()) {
        String tableName = resultSet.getString(3);
        System.out.println(tableName);
    }
} catch (Exception e) {
    e.printStackTrace();
}

References:

• https://stackoverflow.com/questions/4813122/get-all-table-names-set-up-in-sessionfactory
• http://www.herongyang.com/JDBC/sqljdbc-jar-Table-List.html
• http://tutorials.jenkov.com/jdbc/databasemetadata.html

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Exception in thread "main" org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set

Exception in thread "main" org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.determineDialect(DialectFactoryImpl.java:104)
    at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:71)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:209)
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:111)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:234)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:206)
    at org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1885)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1843)
    at com.ranga.MultiTenancyDemo.main(MultiTenancyDemo.java:34)
 

Problem:

// Create the SessionFactory from hibernate.cfg.xml
        Configuration configuration = new Configuration();
       
         System.out.println("Hibernate Configuration loaded.");
       
        //apply configuration property settings to StandardServiceRegistryBuilder
        serviceRegistry = new StandardServiceRegistryBuilder().applySettings(
                configuration.getProperties()).build();
        System.out.println("Hibernate serviceRegistry created.");
       
        sessionFactory = configuration.buildSessionFactory(serviceRegistry);
        System.out.println("Hibernate sessionFactory object created.");    

Solution:

After creation of Configuration object, we need to call the         configuration.configure("hibernate.cfg.xml"); method.

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Exception in thread "main" org.hibernate.HibernateException: persist is not valid without active transaction

Problem:  The problem in Configuration file.

<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">       
        <property name="dataSource" ref="dataSource"></property>       
        <!-- Configuring the  Hibernate properties -->
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">${hibernate.dialect}</prop>
                <prop key="hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
                <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>               
                <prop key="hibernate.current_session_context_class">${hibernate.current_session_context_class}</prop>
            </props>       
        </property>
        <property name="annotatedClasses">
            <list>
                <value>com.ranga.Employee</value>
            </list>
        </property>       
    </bean>

------------------------------------------------------------------------------------------------------------------------------

hibernate.current_session_context_class is required only for JTA transactions.

Solution: Remove the hibernate.current_session_context_class property in sessionFactory. Now the code looks like

<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">       
        <property name="dataSource" ref="dataSource"></property>       
        <!-- Configuring the  Hibernate properties -->
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">${hibernate.dialect}</prop>
                <prop key="hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
                <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>               
            </props>       
        </property>
        <property name="annotatedClasses">
            <list>
                <value>com.ranga.Employee</value>
            </list>
        </property>       
    </bean>

Click here to see more information.

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java.lang.NoClassDefFoundError: org/aopalliance/intercept/MethodInterceptor

Problem:

While doing transactions management with the annotations, prior to Spring 3.0 we are adding aopalliance.jar file. In latest Spring bundle this jar file not available. If we add below line applicationContext.xml we need to add the aopalliance.jar file other wise it will throws the java.lang.NoClassDefFoundError: org/aopalliance/intercept/MethodInterceptor

<tx:annotation-driven transaction-manager="hibernateTransactionManager"/>

Solution: Add the aopalliance.jar file to classpath or pom.xml file.

Click here to Download

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