由於看到一大堆xml檔案就蛋疼,所以本人傾向於用註解來配置spring,經過對比確實也要簡單方便一些,增加功能也可以通過重寫方法來實現,不過這種好像只能在servlet3.0和spring3以上才能用.
首先在config包下一個類,繼承AbstractAnnotationConfigDispatcherServletInitializer類…由於一系列的繼承關係,總之Spring在啟動時就會檢查到我們繼承了這個抽象類的類從而用來配置ServletContext.

 package cn.paul.config;

import org.springframework.context.annotation.Bean;
import
 
 org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;

import javax.servlet.MultipartConfigElement;
import javax.servlet.ServletRegistration;


/**
 * Created by paul on 2017-06-14.
 * 此乃系統入口
 */
 public
 
 class SpringInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {


    @Override
    protected Class<?>[] getRootConfigClasses() {
        return new Class<?>[]{RootConfig.class};
    }


    @Override
    protected Class<?>[] getServletConfigClasses() {
        return
 
 new Class<?>[]{WebMVCConfig.class};
    }

    @Override
    protected String[] getServletMappings() {
        //將DispatcherServlet對映到"/"
        return new String[]{"/"};
    }

    @Override
    protected void customizeRegistration(ServletRegistration.Dynamic registration) {
        registration.setMultipartConfig(new MultipartConfigElement(""));
    }
}

接下來需要寫WebMVCConfig,由於功能簡單隻配置了jsp的處理

package cn.paul.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.web.multipart.MultipartResolver;
import org.springframework.web.multipart.support.StandardServletMultipartResolver;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;

/**
 * Created by paul on 2017-06-14.
 * 該檔案用於配置Spring的檢視解析器,為了解析jsp採用ViewResolver物件
 */
 //該註解表示這是一個配置類
@Configuration
//表示啟用SpringMVC
@EnableWebMvc
//指定掃描的包,我們這裡讓他控制web下的控制器即可
@ComponentScan(basePackages = {"cn.paul.web"})
public class WebMVCConfig extends WebMvcConfigurerAdapter {
    @Bean
    public ViewResolver viewResolver() {
        //配置jsp檢視解析器
        InternalResourceViewResolver resolver =
                new InternalResourceViewResolver();
        //這裡是jsp檔案的路徑對映,我們把jsp檔案放在WEB-INF下的views資料夾中
        resolver.setPrefix("/WEB-INF/views/");
        resolver.setSuffix(".jsp");
        resolver.setViewClass(JstlView.class);
        resolver.setExposeContextBeansAsAttributes(true);
        return resolver;
    }



    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        //配置靜態資源處理
        configurer.enable();
    } 
}

而RootConfig我打算用來配置一些其他的bean,比如mybatis相關的東西.

package cn.paul.config;

import cn.paul.dao.UserDao;
import cn.paul.dao.impl.UserDaoImpl;
import cn.paul.mapper.UserMapper;
import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.annotation.MapperScan;
import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.FilterType;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;

import javax.sql.DataSource;

/**
 * Created by paul on 2017-06-14.
 */
@EnableTransactionManagement
@Configuration
@MapperScan("cn.paul.mapper")
@ComponentScan(basePackages = { "cn.paul" },
        excludeFilters = { @ComponentScan.Filter(type = FilterType.ANNOTATION,
                value = EnableWebMvc.class) })
public class RootConfig {
    @Bean
    public DataSource dataSource() {
        return new ComboPooledDataSource();
    }

    @Bean
    public SqlSessionFactoryBean sqlSessionFactory() throws Exception {
        SqlSessionFactoryBean sqlSessionFactory = new SqlSessionFactoryBean();
        sqlSessionFactory.setDataSource(dataSource());
        sqlSessionFactory.setTypeAliasesPackage("cn.paul.domain");
        return sqlSessionFactory;
    }
 @Bean
    public DataSourceTransactionManager dataSourceTransactionManager() {
        return new DataSourceTransactionManager(dataSource());
    }



}

這裡有一個坑就是@componentScan中設定掃描的包可以是根目錄下所有的包,但是必須要排除有@enableMVC註解的類,不然一會兒Junit會報錯.

一個簡單的mapper類,用來做登入功能,那個@param必須要寫不然會提示找不到引數…還有@repository也要寫上不然 會報紅,但好像不寫也能通過…

package cn.paul.mapper;

import cn.paul.domain.User;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Repository;

/**
 * Created by dell1 on 2017-06-25.
 */
@Repository
public interface UserMapper {
    /**
     * 根據使用者名稱密碼查詢,即登陸功能
     * @param  username
     * @param  password
     * @return 返回user物件
     * */
    @Select("select * from tb_user4 where username=#{username} and password=#{password}")
    User findUser( @Param("username")String username,@Param("password") String password);
}