mybatis + spring 全注解

公司最近起了一个新项目，之前一直使用的是Strut  + Spring + hibernate；由于新项目比较小，使用ssh有点杀鸡用牛刀的意思，经过评估后，感觉mybatis比Hibernate要简单的很多。

 

通过注解的方式开发，可以减少spring和mybatis的很多xml配置，当然spring还是得有部分的xml配置，除非使用spring官网提倡的REST风格；对于REST风格 俺不太熟悉，这里就不献丑啦。

 

咱们使用Maven进行项目开发，在jar管理方面要省心很多。

第一步 加载所需要的jar包，pom.xml的配置如下：

 

         <properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<spring-framework.version>3.2.5.RELEASE</spring-framework.version>
		<mysql.driver.version>5.1.27</mysql.driver.version>
		<c3p0.version>0.9.1.2</c3p0.version>
		<javassist.version>3.17.1-GA</javassist.version>
		<log.slf4j.version>1.7.5</log.slf4j.version>
		<log4j.version>1.2.17</log4j.version>
		<commons.lang.version>2.6</commons.lang.version>
		<servlet.version>2.5</servlet.version>
		<jstl.version>1.2</jstl.version>
		<jsp.version>2.2</jsp.version>
		<tomcat.plugin.version>2.2</tomcat.plugin.version>
		<junit.version>4.11</junit.version>
		<javax.mail.version>1.5.1</javax.mail.version>
		<mybatis-spring.version>1.2.2</mybatis-spring.version>
		<mybatis.version>3.2.7</mybatis.version>
	</properties>

         <dependencies>
			<dependency>
				<groupId>org.springframework</groupId>
				<artifactId>spring-context</artifactId>
				<version>${spring-framework.version}</version>
			</dependency>
			
			<dependency>
			    <groupId>org.springframework</groupId>
			    <artifactId>spring-context-support</artifactId>
			    <version>${spring-framework.version}</version>
			</dependency>

			<dependency>
				<groupId>org.springframework</groupId>
				<artifactId>spring-orm</artifactId>
				<version>${spring-framework.version}</version>
			</dependency>

			<dependency>
				<groupId>c3p0</groupId>
				<artifactId>c3p0</artifactId>
				<version>${c3p0.version}</version>
			</dependency>
			<dependency>
				<groupId>mysql</groupId>
				<artifactId>mysql-connector-java</artifactId>
				<version>${mysql.driver.version}</version>
			</dependency>

			<dependency>
				<groupId>org.slf4j</groupId>
				<artifactId>slf4j-log4j12</artifactId>
				<version>${log.slf4j.version}</version>
			</dependency>

			<dependency>
				<groupId>commons-lang</groupId>
				<artifactId>commons-lang</artifactId>
				<version>${commons.lang.version}</version>
			</dependency>

			<dependency>
				<groupId>junit</groupId>
				<artifactId>junit</artifactId>
				<version>${junit.version}</version>
			</dependency>

			<dependency>
				<groupId>com.sun.mail</groupId>
				<artifactId>javax.mail</artifactId>
				<version>${javax.mail.version}</version>
			</dependency>

			<dependency>
			    <groupId>org.mybatis</groupId>
			    <artifactId>mybatis-spring</artifactId>
			    <version>${mybatis-spring.version}</version>
			</dependency>
			
			<dependency>
			    <groupId>org.mybatis</groupId>
			    <artifactId>mybatis</artifactId>
			    <version>${mybatis.version}</version>
			</dependency>

			<dependency>
			    <groupId>org.springframework</groupId>
			    <artifactId>spring-test</artifactId>
			    <version>${spring-framework.version}</version>
			</dependency>
			
			<dependency>
				<groupId>junit</groupId>
				<artifactId>junit</artifactId>
				<version>${junit.version}</version>
				<scope>test</scope>
			</dependency>
		</dependencies>

   这里主要是加载mybatis-spring和mybatis。

 

第二步 设置mybatis需要的sqlSessionFactory，并且让mybatis自动加载Mapper接口(该接口在下面会说)

 

	<context:property-placeholder location="classpath:spring/jdbc.properties" />

	<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
		destroy-method="close">

		<!-- 解决初次链接 链接已被释放 start -->
		<property name="acquireRetryAttempts" value="30" />
		<property name="acquireRetryDelay" value="1000" />
		<property name="testConnectionOnCheckin" value="true" />
		<property name="automaticTestTable" value="C3P0TestTable" />
		<property name="idleConnectionTestPeriod" value="14400" />
		<property name="checkoutTimeout" value="3000" />
		<!-- 解决初次链接 链接已被释放 end -->

		<property name="driverClass" value="${jdbc.driver}" />
		<property name="jdbcUrl" value="${jdbc.url}" />
		<property name="user" value="${jdbc.username}" />
		<property name="password" value="${jdbc.password}" />
		<property name="initialPoolSize" value="${jdbc.initialPoolSize}" />
		<property name="minPoolSize" value="${jdbc.minPoolSize}" />
		<property name="maxPoolSize" value="${jdbc.maxPoolSize}" />
	</bean>

	<!-- sql session factory to create sql session -->
	<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
		<property name="dataSource" ref="dataSource" />
	</bean>

	<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
		<property name="basePackage" value="com.wangjin.admin.mapper" />
	</bean>

	<!-- configuration for transaction -->
	<bean id="transactionManager"
		class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
		<property name="dataSource" ref="dataSource" />
	</bean>

 

 

 

第三步 书写Mapper 接口，该接口相当于普通项目的Dao类，但是该Mapper是接口的形式并且通过注解的方式进行sql声明，mybatis会通过代理的方式执行相应的sql，在第二步中已经设置了让mybatis来加载Mapper接口。

 

public interface AdminUserMapper {
	
	@Insert("insert into admin_user(username, password) values(#{username}, #{password})")
	@SelectKey(statement="SELECT last_insert_id() as id", keyProperty="id", before=false, resultType=int.class)
	public int add(AdminUser adminUser);
	
	@Delete("delete from admin_user where id=#{id}")
	public void delete(@Param("id")int id);
	
	@Update("update admin_user set username=#{username}, password=#{password} where id=#{id}")
	public void update(AdminUser adminUser);
	
	@Select("select * from admin_user")
	public List<AdminUser> loadAll();
	
	@Select("select * from admin_user limit #{start}, #{size}")
	public List<AdminUser> loadAllLimit(@Param("start")int start, @Param("size")int size);
	
	@Select("select * from admin_user where id=#{id}")
	public AdminUser getById(@Param("id")int id);
	
	@Select("select * from admin_user where username=#{username}")
	public AdminUser getByUsername(@Param("username")String username);

}

这里要注意在Mapper中一定不要有相同名称的方法，要不然会出错。 

 

@SelectKey(statement="SELECT last_insert_id() as id", keyProperty="id", before=false, resultType=int.class)

这句注解表示插入成功后，将主键设置到adminUser中, 当然AdminUser一定要有id的set方法， AdminUser的详情如下

 

public class AdminUser {
	private int id;
	private String username;
	private String password;
	
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}

}

 

 

第四步 在service中使用Mapper接口（相当于在service中使用Dao），你会发现以前需要进行Dao的接口设计以及Dao接口的实现，很麻烦，现在这些都不需要啦，只需要定义Mapper接口，然后定义相关的接口方法，在相关的方法上声明sql语句，然后在service中就可以使用该接口啦。

 

public interface AdminUserService {
	
	public int addAdminUser(AdminUser adminUser);
	
	public void deleteAdminUserById(int id);
	
	public void updateAdminUser(AdminUser adminUser);
	
	public AdminUser getByUsername(String username);
	
	public List<AdminUser> loadAllAdminUsers();
	
	public List<AdminUser> loadAllAdminUsers(int start, int size);

}

/**
 * service for admin user
 * @author kinfer
 *
 */
@Service
public class AdminUserServiceImpl implements AdminUserService {
	@Autowired
	private AdminUserMapper adminUserMapper;

	@Override
	@Transactional
	public int addAdminUser(AdminUser adminUser) {
		
		return adminUserMapper.add(adminUser);
	}

	@Override
	@Transactional
	public void deleteAdminUserById(int id) {
		
		adminUserMapper.delete(id);
	}

	@Override
	@Transactional
	public void updateAdminUser(AdminUser adminUser) {
		
		adminUserMapper.update(adminUser);
	}

	@Override
	@Transactional(readOnly=true)
	public AdminUser getByUsername(String username) {
		
		return adminUserMapper.getByUsername(username);
	}

	@Override
	@Transactional(readOnly=true)
	public List<AdminUser> loadAllAdminUsers() {
		
		return adminUserMapper.loadAll();
	}

	@Override
	@Transactional(readOnly=true)
	public List<AdminUser> loadAllAdminUsers(int start, int size) {
		
		return adminUserMapper.loadAllLimit(start, size);
	}

}

 

第五步 测试，我使用的是springjunit

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations="classpath:spring/business-config.xml")
public class AdminUserServiceTester {
	@Autowired
	private AdminUserService service;
	
	@Test
	public void addTest(){
		
		AdminUser adminUser = service.getByUsername("kinfer");
		if(adminUser != null){
			
			service.deleteAdminUserById(adminUser.getId());
		} else{
			adminUser = new AdminUser();
			adminUser.setUsername("kinfer");
			adminUser.setPassword("0000");
			
		}
		
		int result = service.addAdminUser(adminUser);
		Assert.assertTrue(result > 0);
		Assert.assertTrue(adminUser.getId() > 0);
		
		adminUser = service.getByUsername("kinfer");
		Assert.assertTrue(adminUser != null);
		Assert.assertEquals("kinfer", adminUser.getUsername());
		
		adminUser.setUsername("kinfer1");
		service.updateAdminUser(adminUser);
		adminUser = service.getByUsername("kinfer1");
		Assert.assertTrue(adminUser != null);
		Assert.assertEquals("kinfer1", adminUser.getUsername());
		
		adminUser.setUsername("kinfer");
		service.updateAdminUser(adminUser);
	}
}

  

完成spring+mybatis配置，是不是很easy.