CODEWITHSUNDEEP
javaspringspring-mvcinversion-of-control
SocketM
SocketM

Reputation: 574

Exception in thread "main" org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named

I'm using the following configuration for Sprinc IOC container. My app-config.xml is:

    <?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:mvc="http://www.springframework.org/schema/mvc"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">



   <bean id="myDatasource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url" value="jdbc:mysql://localhost:3306/bus_db" />
        <property name="username" value="sysadmin" />
        <property name="password" value="adminadmin" />
   </bean>

<!--    <context:property-placeholder location="src/main/java/com/bus/assets/dbinfo.properties" />  -->


   </beans>

My project sutructure is:

enter image description here

My Bean class that will be used for injection is:

    package com.bus.dao;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import javax.sql.DataSource;

import com.bus.model.Bus;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Component;

@Component("busDAO")
public class BusDAO {

    private JdbcTemplate myJdbcTemplate;

    public List<Bus> getBusList(){
        return myJdbcTemplate.query("select * from bus.bus", 
                new RowMapper<Bus>() {

                    @Override
                    public Bus mapRow(ResultSet rs, int rowNum) throws SQLException {
                        // TODO Auto-generated method stub
                        Bus bus = new Bus();
                        bus.setBrandName(rs.getString("brand_name"));
                        bus.setBusId(rs.getInt("bus_id"));
                        bus.setBusNumber(rs.getString("bus_number"));
                        bus.setModelNumber("model_number");
                        //bus.setProdDate(prodDate);
                        return bus;
                    }

        });
    }

    public JdbcTemplate getMyJdbcTemplate() {
        return myJdbcTemplate;
    }

    @Autowired
    public void setMyJdbcTemplate(DataSource ds) {
        this.myJdbcTemplate = new JdbcTemplate(ds);
    }

}

However, when I try to test Spring bean injection I'm getting the error that the bean named "busDAO" could not be found. I've also outputed into my Spring Tool Suite console the array of existing beans which is empty. 

public class TestConnection {

public static void main(String[] args) {
    // TODO Auto-generated method stub


    ApplicationContext appcon = new FileSystemXmlApplicationContext("/src/main/webapp/WEB-INF/config/app-config.xml");
    System.out.println("Bean names: " + Arrays.toString(appcon.getBeanNamesForType(BusDAO.class)));


    BusDAO myBusDAO =  appcon.getBean("busDAO", BusDAO.class);

    List<Bus> myBusList = myBusDAO.getBusList();

    for(Bus b: myBusList) {
        System.out.println(b.toString());
    }

}

}

What I could do better in order to allow my Spring Bean context to find the missing bean?

Upvotes: 0

Views: 1420

Answers (3)

SocketM
SocketM

Reputation: 574

What I have done: added a property named private DataSource dataSource to busDAO 

@Component("busDAO")
public class BusDAO {

    private JdbcTemplate myJdbcTemplate;
    private DataSource dataSource;
    .....
public void setDataSource(DataSource dataSource) {
          this.dataSource = dataSource;
          this.myJdbcTemplate = new JdbcTemplate(dataSource);
       }

and after that configured the bean acordingly in xml configuration: <bean id="busDAO" class="com.bus.dao.BusDAO"> <property name="dataSource" ref="dataSource" /> </bean>

Upvotes: 0

Stefan Helmerichs
Stefan Helmerichs

Reputation: 502

You either need to add context:component-scan element to the app-config.xml or instantiate the bean manually:

<bean id="busDAO" class="com.bus.dao.BusDAO">
  <!-- specifics omitted as i am not that good with xml config -->
</bean>

The option to instantiate manually in an @Configuration annotated class will, again, require the context:component-scan element, or a bean definition of said class:

<bean id="myConfiguratioClass" class="com.bus.configuration.MyConfigClass" />

Upvotes: 1

Anirudh Simha
Anirudh Simha

Reputation: 360

  • The problem here is there seems to be a confusion between @Component and @Bean.
  • What you need to do is create another class, annotate it with @Configuration.
  • In this class, you should create a function annotated with @Bean and this function should return your initiated Dao.

  • I might add the code for it if required.

    @Configuration public class DaoConfiguration{ @Bean public BusDAO dao { return new BusDAO(); } }

And you can use this bean using @Autowired BusDAO busDao

I'm sorry for the badly formatted code :)

Upvotes: 1

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