(转)Spring集成MyBatis进行项目开发（二）

原文出处：http://wangjie2013.iteye.com/blog/1996151

上一章Spring集成MyBatis进行项目开发（一）已经介绍了spring和mybatis整合的配置，接下来是一个项目里面的部分代码：

    Application.java是下面会用到的一个实体bean：

 

public class Application {

    public static final int APP_DISABLE = 0;
    public static final int APP_ENABLE = 1;
    private Integer id;
    private String appAccount;//每个app对应一个账户标识；对应生成的数据表
    private String appName;
    private String appICON;
    private String appDesc;
    private String appURL;
    private Date createTime;
    private int isDisable;//'是否前台显示：0显示，1不显示'
}

    getter 和setter略。

 

 

    首先我们要编写一个与mapper.xml文件映射的接口文件，mybatis会将这个接口文件和对应的mapper文件中的sql语句关联，自动实现这个接口文件。在之后的开发中我们直接调用这个接口文件就可以了，因为内存中已经有接口相对应的实例了。

ApplicationsMapper.xml文件：

 

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
    "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.pinche.statistic.mapper.ApplicationsMapper">

    <insert id="add" parameterType="Application" useGeneratedKeys="true"
        keyProperty="id">
        INSERT INTO applications
        (appName,appAccount,appICON,appDesc,appURL,createTime)
        VALUES
        (#{appName},#{appAccount},#{appICON},#{appDesc},#{appURL},#{createTime})
    </insert>

    <delete id="delete" parameterType="String">
        DELETE FROM applications WHERE
        appAccount = #{appAccount}
    </delete>

    <update id="update" parameterType="Application">
        UPDATE applications
        <set>
            <if test=" appName != '' and appName != null ">
                appName = #{appName},
            </if>
            <if test=" appICON != '' and appICON != null ">
                appICON = #{appICON},
            </if>
            <if test=" appDesc != '' and appDesc != null ">
                appDesc = #{appDesc},
            </if>
            <if test=" appURL != '' and appURL != null ">
                appURL = #{appURL},
            </if>
            <if test=" isDisable != -1 ">
                isDisable = #{isDisable}
            </if>
        </set>
        WHERE appAccount = #{appAccount}
    </update>

    <select id="findByAppAccount" resultType="Application"
        parameterType="String">
        select * from applications where appAccount =
        #{appAccount}
    </select>

    <select id="findAll" resultType="Application">
        select * from applications
    </select>
</mapper>

    对ApplicationsMapper.xml文件的配置必须要注意的是它的命名空间是必须的，而且是对应接口文件的全名！并且每个sql语句的id属性和接口文件中的方法名一致！！

 

 

    下面是ApplicationsMapper.java文件，也就是对应的接口文件：

 

package com.pinche.statistic.mapper;

import java.util.List;

import com.pinche.statistic.domain.Application;

public interface ApplicationsMapper {

    void add(Application app);

    void delete(String appAccount);

    void update(Application app);

    Application findByAppAccount(String appAccount);

    List<Application> findAll();
}

 

 

    通过以上的的配置，大家可以在test中测试一下自己的代码了：

@Test
public void testCreateTable() {
    ApplicationContext aContext = new FileSystemXmlApplicationContext("src/main/webapp/WEB-INF/applicationContext.xml");
    ApplicationsMapper mapper = (ApplicationsMapper) aContext.getBean(ApplicationsMapper.class);

    Application app = new Application();
    app.setAppAccount("androidApp");

    mapper.add(app);
}

 

    以上测试了add方法，其他的测试方法大家可以照着写一写。如果插入成功恭喜，你的环境已经搭好了。

 

 

    接下来是将继续这个样例系统的Dao层，service层和controller层。

    AppDao.java

 

package com.pinche.statistic.dao;

import java.util.List;

import com.pinche.statistic.domain.Application;

public interface AppDao {
    boolean add(Application app);

    boolean delete(String appAccount);

    boolean update(Application app);

    Application findByAppAccount(String appAccount);

    List<Application> findAll();
}

 

     AppDaoImpl.java

 

 

package com.pinche.statistic.dao.impl;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.dao.DataAccessException;
import org.springframework.stereotype.Repository;

import com.pinche.statistic.dao.AppDao;
import com.pinche.statistic.domain.Application;
import com.pinche.statistic.mapper.ApplicationsMapper;

@Repository
public class AppDaoImpl implements AppDao {

    @Autowired
    private ApplicationsMapper mapper;

    @Override
    public boolean add(Application app) {
        try {
            mapper.add(app);
            return true;
        } catch (DataAccessException e) {
            e.printStackTrace();
        }
        return false;
    }

    @Override
    public boolean delete(String appAccount) {
        try {
            mapper.delete(appAccount);
            return true;
        } catch (DataAccessException e) {
            e.printStackTrace();
        }
        return false;
    }

    @Override
    public boolean update(Application app) {
        try {
            mapper.update(app);
            return true;
        } catch (DataAccessException e) {
            e.printStackTrace();
        }
        return false;
    }

    @Override
    public Application findByAppAccount(String appAccount) {
        try {
            Application findByAppAccount = mapper.findByAppAccount(appAccount);
            return findByAppAccount;
        } catch (DataAccessException e) {
            e.printStackTrace();
        }
        return null;
    }

    @Override
    public List<Application> findAll() {
        try {
            return mapper.findAll();
        } catch (DataAccessException e) {
            e.printStackTrace();
        }
        return null;
    }
}

 

 

    自行设计的DAO层对象容器（在DAO对象很多时，如果在service层要调用对应的DAO还得手动注入，通过引用这个DAO层对象容器，可以实现在需要使用DAO时迅速找需要的DAO，省去了繁杂的手动注入，而且spring默认的bean都是单例的，无论在何处注入一个实体bean其实都是同一个。这样做更方便）：

 

package com.pinche.statistic.dao;

import java.lang.reflect.Field;

import javax.annotation.PostConstruct;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

@Repository
public class BaseDAL {

    private static final Logger logger = LoggerFactory.getLogger(BaseDAL.class);

    @Autowired
    private AppDao _appDao;
    public static AppDao appDao;

    @Autowired
    private MetaDataDao _metaDataDao;
    public static MetaDataDao metaDataDao;

    @Autowired
    private DDLManager _DDLManager;
    public static DDLManager DDLManager;

    @Autowired
    private AnalyzeDao _analyzeDao;
    public static AnalyzeDao analyzeDao;

    @Autowired
    private DialstatisticsDao _dialstatisticsDao;
    public static DialstatisticsDao dialstatisticsDao;

    @PostConstruct
    public void init() {
        long start = System.currentTimeMillis();
        logger.debug("start init BaseDAL ...");
        try {

            Field[] fields = this.getClass().getDeclaredFields();

            for (int i = 0; i < fields.length; i++) {
                String fieldname = fields[i].getName();
                if (fieldname.startsWith("_")) {
                    String sfieldname = fieldname.substring(1);
                    Field sfield = this.getClass().getDeclaredField(sfieldname);
                    sfield.setAccessible(true);
                    sfield.set(this, fields[i].get(this));
                }
            }
            logger.debug("init BaseDAL OVER, consume = {}ms",
                    System.currentTimeMillis() - start);
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }
}

 

 

    如果使用了以上的层管理容器，如果要在容器中添加一个DAO（例如：DemoDao），只需在这个容器中添加一个这样的声明：

 

@Autowired
private DemoDao _demoDao;
public static DemoDao demoDao;

 

 

    好了下面是Service层定义的接口：

    AppService.java

 

package com.pinche.statistic.service;

import java.util.List;

import com.pinche.statistic.domain.Application;

/**
 * @author JACKWANG
 * @since Dec 23, 2013
 */
public interface AppService {

    Application find(String appAccount);

    boolean update(Application app);

    boolean setDisable(String appAccount);

    boolean setEnable(String appAccount);

    List<Application> findAll();

}

 

 

    AppServiceImpl.java : AppService的实现类：

 

package com.pinche.statistic.service.impl;

import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;

import com.pinche.statistic.dao.BaseDAL;
import com.pinche.statistic.domain.Application;
import com.pinche.statistic.service.AppService;
import com.pinche.statistic.utils.SystemUtils;

/**
 * @author JACKWANG
 * @since Dec 23, 2013
 */
@Service
public class AppServiceImpl implements AppService {

    private static final Logger logger = LoggerFactory
            .getLogger(AppServiceImpl.class);

    @Override
    public Application find(String appAccount) {
        return BaseDAL.appDao.findByAppAccount(appAccount);
    }


    @Override
    public boolean update(Application app) {
        String appAccount = app.getAppAccount();
        if (appAccount == null && "".equals(appAccount)) {
            return true;
        }
        return BaseDAL.appDao.update(app);
    }

    @Override
    public boolean setDisable(String appAccount) {
        Application app = new Application();
        app.setAppAccount(appAccount);
        app.setIsDisable(Application.APP_DISABLE);
        return BaseDAL.appDao.update(app);
    }

    @Override
    public boolean setEnable(String appAccount) {
        Application app = new Application();
        app.setAppAccount(appAccount);
        app.setIsDisable(Application.APP_ENABLE);
        return BaseDAL.appDao.update(app);
    }

    @Override
    public List<Application> findAll() {
        return BaseDAL.appDao.findAll();
    }
}

   

     哈哈，使用层对象管理容器是不是很方便。通过一个引用就能获得所有的DAO支持。所以我在service层也构建了一个service层对象管理容器BaseBLL:

 

 

    BaseBLL.java:

 

package com.pinche.statistic.service;

import java.lang.reflect.Field;

import javax.annotation.PostConstruct;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

/**
 * @author JACKWANG
 * @since Dec 23, 2013
 */
@Service
public class BaseBLL {

    private static final Logger logger = LoggerFactory.getLogger(BaseBLL.class);

    @Autowired
    private AnalyzeService _analyzeService;
    public static AnalyzeService analyzeService;

    @Autowired
    private AppService _appService;
    public static AppService appService;

    @Autowired
    private MetaDataService _metaDataService;
    public static MetaDataService metaDataService;

    @PostConstruct
    public void init() {
        long start = System.currentTimeMillis();
        logger.debug("start init BaseBLL ...");
        try {

            Field[] fields = this.getClass().getDeclaredFields();

            for (int i = 0; i < fields.length; i++) {
                String fieldname = fields[i].getName();
                if (fieldname.startsWith("_")) {
                    String sfieldname = fieldname.substring(1);
                    Field sfield = this.getClass().getDeclaredField(sfieldname);
                    sfield.setAccessible(true);
                    sfield.set(this, fields[i].get(this));
                }
            }
            logger.debug("init BaseBLL OVER, consume = {}ms",
                    System.currentTimeMillis() - start);
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }

}

   

 

 

    好了下面应该是controller层的编写了，但是由于笔者以上的代码只是摘录了系统中的部分，而在controller中涉及到其他的内容，如果直接摘录可能和以上的代码衔接不上。所以这里就不进行了controller层的具体介绍了。本系统controller层使用的是SpringMVC，开发效率一级赞。