Spring集成MyBatis进行项目开发（二）

 

    上一章Spring集成MyBatis进行项目开发（一）已经介绍了spring3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。

    这个dao层吧，项目中就是这么用的，不过现在通过大家的指正，mybatis提供了@param来解决多参数问题，ok，这么看来这个Dao层的确不需要了。

 

    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();
}

 

     对应的实现类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。

 

 

评论

1 楼 Inmethetiger 2013-12-30  

DaoImpl 还需要写吗？