Java/Spring/ResultSetExtractor

Implements ResultSetExtractor to get the data from first column

   <source lang="java">

File: context.xml <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans"

      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xmlns:util="http://www.springframework.org/schema/util"
      xmlns:tx="http://www.springframework.org/schema/tx"
      xmlns:aop="http://www.springframework.org/schema/aop"
      xmlns:lang="http://www.springframework.org/schema/lang"
      xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
                          http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-2.0.xsd
                          http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
                          http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd
                          http://www.springframework.org/schema/lang http://www.springframework.org/schema/lang/spring-lang-2.0.xsd">

   <bean id="dataSource" class="org.apache.rumons.dbcp.BasicDataSource" destroy-method="close">
   <property name="driverClassName" value="org.hsqldb.jdbcDriver"/>
   <property name="url" value="jdbc:hsqldb:mem:."/>
   <property name="username" value="sa"/>
   <property name="password" value=""/>
   </bean>

   <bean id="lobHandler" class="org.springframework.jdbc.support.lob.OracleLobHandler">
       <property name="nativeJdbcExtractor" ref="nativeJdbcExtractor"/>
   </bean>
   <bean id="nativeJdbcExtractor" class="org.springframework.jdbc.support.nativejdbc.rumonsDbcpNativeJdbcExtractor"/>
   <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
       <property name="dataSource" ref="dataSource"/>
   </bean>

</beans>

File: Main.java import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import javax.sql.DataSource; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.dao.DataAccessException; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.jdbc.core.PreparedStatementSetter; import org.springframework.jdbc.core.ResultSetExtractor; class Main {

 public static void main(String args[]) throws Exception {
   ApplicationContext ac = new ClassPathXmlApplicationContext("context.xml", Main.class);
   DataSource dataSource = (DataSource) ac.getBean("dataSource");
   // DataSource mysqlDataSource = (DataSource) ac.getBean("mysqlDataSource");
   JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
   String firstCustomersName = (String) jdbcTemplate.query(
       "select first_name from t_customer where id=?", new PreparedStatementSetter() {
         public void setValues(PreparedStatement preparedStatement) throws SQLException {
           preparedStatement.setLong(1, 1L);
         }
       }, new FirstColumnStringExtractor());
   System.out.println(firstCustomersName);
 }

} class FirstColumnStringExtractor implements ResultSetExtractor {

 public Object extractData(ResultSet resultSet) throws SQLException, DataAccessException {
   if (resultSet.next()) {
     return resultSet.getString(1);
   }
   return null;
 }

}

      </source>
   
  
 
  

PreparedStatementCreator And ResultSetExtractor

   <source lang="java">
      

File: context.xml <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans"

      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xmlns:util="http://www.springframework.org/schema/util"
      xmlns:tx="http://www.springframework.org/schema/tx"
      xmlns:aop="http://www.springframework.org/schema/aop"
      xmlns:lang="http://www.springframework.org/schema/lang"
      xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
                          http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-2.0.xsd
                          http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
                          http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd
                          http://www.springframework.org/schema/lang http://www.springframework.org/schema/lang/spring-lang-2.0.xsd">

   <bean id="dataSource" class="org.apache.rumons.dbcp.BasicDataSource" destroy-method="close">
   <property name="driverClassName" value="org.hsqldb.jdbcDriver"/>
   <property name="url" value="jdbc:hsqldb:mem:."/>
   <property name="username" value="sa"/>
   <property name="password" value=""/>
   </bean>

   <bean id="lobHandler" class="org.springframework.jdbc.support.lob.OracleLobHandler">
       <property name="nativeJdbcExtractor" ref="nativeJdbcExtractor"/>
   </bean>
   <bean id="nativeJdbcExtractor" class="org.springframework.jdbc.support.nativejdbc.rumonsDbcpNativeJdbcExtractor"/>
   <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
       <property name="dataSource" ref="dataSource"/>
   </bean>

</beans>

File: Main.java import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import javax.sql.DataSource; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.dao.DataAccessException; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.jdbc.core.PreparedStatementCreator; import org.springframework.jdbc.core.PreparedStatementSetter; import org.springframework.jdbc.core.ResultSetExtractor; class Main {

 public static void main(String args[]) throws Exception {
   ApplicationContext ac = new ClassPathXmlApplicationContext("context.xml", Main.class);
   DataSource dataSource = (DataSource) ac.getBean("dataSource");
   // DataSource mysqlDataSource = (DataSource) ac.getBean("mysqlDataSource");
   JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
   Long maxId = (Long) jdbcTemplate.query(new PreparedStatementCreator() {
     public PreparedStatement createPreparedStatement(Connection connection) throws SQLException {
       return connection.prepareStatement("select max(id) from customer");
     }
   }, new ResultSetExtractor() {
     public Object extractData(ResultSet resultSet) throws SQLException, DataAccessException {
       if (resultSet.next()) {
         return resultSet.getLong(1);
       }
       return null;
     }
   });
   System.out.println(maxId);
 }

}

      </source>
   
  
 
  

ResultSetExtractor With Aggregate Function

   <source lang="java">
      

File: context.xml <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans"

      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xmlns:util="http://www.springframework.org/schema/util"
      xmlns:tx="http://www.springframework.org/schema/tx"
      xmlns:aop="http://www.springframework.org/schema/aop"
      xmlns:lang="http://www.springframework.org/schema/lang"
      xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
                          http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-2.0.xsd
                          http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
                          http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd
                          http://www.springframework.org/schema/lang http://www.springframework.org/schema/lang/spring-lang-2.0.xsd">

   <bean id="dataSource" class="org.apache.rumons.dbcp.BasicDataSource" destroy-method="close">
   <property name="driverClassName" value="org.hsqldb.jdbcDriver"/>
   <property name="url" value="jdbc:hsqldb:mem:."/>
   <property name="username" value="sa"/>
   <property name="password" value=""/>
   </bean>

   <bean id="lobHandler" class="org.springframework.jdbc.support.lob.OracleLobHandler">
       <property name="nativeJdbcExtractor" ref="nativeJdbcExtractor"/>
   </bean>
   <bean id="nativeJdbcExtractor" class="org.springframework.jdbc.support.nativejdbc.rumonsDbcpNativeJdbcExtractor"/>
   <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
       <property name="dataSource" ref="dataSource"/>
   </bean>

</beans>

File: Main.java import java.sql.ResultSet; import java.sql.SQLException; import javax.sql.DataSource; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.dao.DataAccessException; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.jdbc.core.ResultSetExtractor; class Main {

 public static void main(String args[]) throws Exception {
   ApplicationContext ac = new ClassPathXmlApplicationContext("context.xml", Main.class);
   DataSource dataSource = (DataSource) ac.getBean("dataSource");
   // DataSource mysqlDataSource = (DataSource) ac.getBean("mysqlDataSource");
   JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
   Long count = (Long) jdbcTemplate.query("select count(*) from customer",
       new ResultSetExtractor() {
         public Object extractData(ResultSet resultSet) throws SQLException, DataAccessException {
           if (resultSet.next()) {
             return resultSet.getLong(1);
           }
           return null;
         }
       });
   System.out.println(count);
 }

}

      </source>