title: No unique bean of type [] is defined: expected single matching bean but found 2: [dbImpl, DbImpl]
body: <p>Hi I am new to Spring: I have a problem  related  with the configuration of my project;</p>
  
  <p>this is my servlet-context.xml:</p>
  
  <pre><code>    &lt;?xml version="1.0" encoding="UTF-8"?&gt;
      &lt;beans:beans xmlns="http://www.springframework.org/schema/mvc"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xmlns:beans="http://www.springframework.org/schema/beans"
      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"&gt;
  
      &lt;!-- DispatcherServlet Context: defines this servlet's request-processing infrastructure --&gt;
  
      &lt;!-- Enables the Spring MVC @Controller programming model --&gt;
      &lt;annotation-driven /&gt;
  
      &lt;!-- Handles HTTP GET requests for /resources/** by efficiently serving up static resources in the ${webappRoot}/resources directory --&gt;
      &lt;resources mapping="/resources/**" location="/resources/" /&gt;
  
      &lt;!-- Resolves views selected for rendering by @Controllers to .jsp resources in the /WEB-INF/views directory --&gt;
  
      &lt;beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"&gt;
          &lt;beans:property name="prefix" value="/WEB-INF/views/" /&gt;
          &lt;beans:property name="suffix" value=".jsp" /&gt;
      &lt;/beans:bean&gt;
  
      &lt;context:component-scan base-package="com.metmi.mmasgis" /&gt;
  
      &lt;beans:bean id="DbImpl" class="com.metmi.mmasgis.dao.DbImpl"&gt;
          &lt;beans:property name="dataSource" ref="dataSource" /&gt;
  
      &lt;/beans:bean&gt;
  
  
  
      &lt;beans:bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"&gt;
          &lt;beans:property name="driverClassName"
              value="com.mysql.jdbc.Driver"&gt;
          &lt;/beans:property&gt;
          &lt;beans:property name="username" value="root"&gt;&lt;/beans:property&gt;
          &lt;beans:property name="password" value="vilu7240"&gt;&lt;/beans:property&gt;
          &lt;beans:property name="url"
              value="jdbc:mysql://localhost:3306/springschema"&gt;
          &lt;/beans:property&gt;
      &lt;/beans:bean&gt;
  &lt;/beans:beans&gt;
  </code></pre>
  
  <p>this is my controller:</p>
  
  <pre><code>    package com.metmi.mmasgis;
  
  import java.text.DateFormat;
  import java.util.ArrayList;
  import java.util.Date;
  import java.util.Locale;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.stereotype.Controller;
  import org.springframework.ui.Model;
  import org.springframework.web.bind.annotation.RequestMapping;
  import org.springframework.web.bind.annotation.RequestMethod;
  
  import com.metmi.mmasgis.dao.DbImpl;
  import com.metmi.mmasgis.model.Db;
  
  /**
   * Handles requests for the application home page.
   */
  @Controller
  public class HomeController {
      @Autowired
      DbImpl dbs;
      private static final Logger logger = LoggerFactory
              .getLogger(HomeController.class);
  
      /**
       * Simply selects the home view to render by returning its name.
       */
      @RequestMapping(value = "/", method = RequestMethod.GET)
      public String home(Locale locale, Model model) {
          logger.info("Welcome home! The client locale is {}.", locale);
  
          Date date = new Date();
          DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG,
                  DateFormat.LONG, locale);
  
          String formattedDate = dateFormat.format(date);
  
          model.addAttribute("serverTime", formattedDate);
  
          return "home";
      }
  
      /**
       * get the database list in Mysql
       */
      @RequestMapping(value = "/db", method = RequestMethod.GET)
      public String dbs(Locale locale, Model model) {
          ArrayList&lt;Db&gt; dbList = dbs.getDatabases();
          model.addAttribute("dbList", dbList);
          return "dbs";
      }
  
      /**
       * Simply shows ciao.
       */
      @RequestMapping(value = "/ciao", method = RequestMethod.GET)
      public String ciao(Locale locale, Model model) {
          logger.info("Welcome home! The client locale is {}.", locale);
  
          Date date = new Date();
          DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG,
                  DateFormat.LONG, locale);
  
          String formattedDate = dateFormat.format(date);
  
          model.addAttribute("serverTime", formattedDate);
  
          return "ciao";
      }
  
  }
  </code></pre>
  
  <p>It is pretty basic, I get this error when I run it on the server:</p>
  
  <pre><code>org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'homeController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.metmi.mmasgis.dao.DbImpl com.metmi.mmasgis.HomeController.dbs; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No unique bean of type [com.metmi.mmasgis.dao.DbImpl] is defined: expected single matching bean but found 2: [dbImpl, DbImpl]
  </code></pre>