- xml配置
Mybatis的所有操作都是基于一個SqlSession的旨椒，而SqlSession是由SqlSessionFactory來產(chǎn)生的综慎，SqlSessionFactory又是由SqlSessionFactoryBuilder來生成的示惊。但是Mybatis-Spring是基于SqlSessionFactoryBean的愉镰。在使用Mybatis-Spring的時候，我們也需要SqlSession阔拳，而且這個SqlSession是內(nèi)嵌在程序中的类嗤，一般不需要我們直接訪問。SqlSession也是由SqlSessionFactory來產(chǎn)生的货裹，但是Mybatis-Spring給我們封裝了一個SqlSessionFactoryBean精偿，在這個bean里面還是通過SqlSessionFactoryBuilder來建立對應(yīng)的SqlSessionFactory，進(jìn)而獲取到對應(yīng)的SqlSession搔预。通過SqlSessionFactoryBean我們可以通過對其指定一些屬性來提供Mybatis的一些配置信息
通過MapperFactoryBean可以獲取到我們想要的Mapper對象拯田。MapperFactoryBean實現(xiàn)了Spring的FactoryBean接口甩十，所以MapperFactoryBean是通過FactoryBean接口中定義的getObject方法來獲取對應(yīng)的Mapper對象的吭产。在定義一個MapperFactoryBean的時候有兩個屬性需要我們注入臣淤，一個是Mybatis-Spring用來生成實現(xiàn)了SqlSession接口的SqlSessionTemplate對象的sqlSessionFactory窃爷；另一個就是我們所要返回的對應(yīng)的Mapper接口了。
定義好相應(yīng)Mapper接口對應(yīng)的MapperFactoryBean之后寺董，我們就可以把我們對應(yīng)的Mapper接口注入到由Spring管理的bean對象中了刻剥，比如Service bean對象。這樣當(dāng)我們需要使用到相應(yīng)的Mapper接口時御吞，MapperFactoryBean會從它的getObject方法中獲取對應(yīng)的Mapper接口陶珠，而getObject內(nèi)部還是通過我們注入的屬性調(diào)用SqlSession接口的getMapper(Mapper接口)方法來返回對應(yīng)的Mapper接口的享钞。這樣就通過把SqlSessionFactory和相應(yīng)的Mapper接口交給Spring管理實現(xiàn)了Mybatis跟Spring的整合
<bean id="sqlSessionFactory"
class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="datasource"></property>
<property name="configLocation" value="classpath:context/mybatis-config.xml"></property>
<!--
mapperLocations：通過正則表達(dá)式，支持mybatis動態(tài)掃描添加mapper不用像ibatis暑脆，用一個還要蛋疼滴添加一個include
-->
<property name="mapperLocations" value="classpath*:/com/tx/demo/**/*SqlMap.xml" />
<!--
typeHandlersPackage: 由于mybatis默認(rèn)入?yún)⑷绻麨榭仗砺穑譀]有指定jdbcType時會拋出異常份名，在這里通過配置一些默認(rèn)的類型空值插入的handle，以便處理mybatis的默認(rèn)類型為空的情況鲤孵。
例如NullAbleStringTypeHandle通過實現(xiàn)當(dāng)String字符串中為null是調(diào)用ps.setString(i,null)其他常用類型雷同辰如。
-->
<property name="typeHandlersPackage" value="com.tx.core.mybatis.handler"></property>
<!--
failFast：開啟后將在啟動時檢查設(shè)定的parameterMap,resultMap是否存在，是否合法鹰椒。個人建議設(shè)置為true,這樣可以盡快定位解決問題漆际。不然在調(diào)用過程中發(fā)現(xiàn)錯誤夺饲，會影響問題定位。
-->
<property name="failFast" value="true"></property>
<property name="plugins">
<array>
<bean class="com.tx.core.mybatis.interceptor.PagedDiclectStatementHandlerInterceptor">
<property name="dialect">
<bean class="org.hibernate.dialect.PostgreSQLDialect"></bean>
</property>
</bean>
</array>
</property>
</bean>
<!--
myBatisExceptionTranslator：用以支持spring的異常轉(zhuǎn)換擂找，通過配置該translator可以將mybatis異常轉(zhuǎn)換為spring中定義的DataAccessException贯涎。
-->
<bean id="myBatisExceptionTranslator" class="org.mybatis.spring.MyBatisExceptionTranslator">
<property name="dataSource">
<ref bean="datasource"></ref>
</property>
</bean>
<bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
<constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory"></constructor-arg>
<constructor-arg name="executorType" ref="SIMPLE"></constructor-arg>
<constructor-arg name="exceptionTranslator" ref="myBatisExceptionTranslator"></constructor-arg>
</bean>
<bean id="myBatisDaoSupport" class="com.tx.core.mybatis.support.MyBatisDaoSupport">
<property name="sqlSessionTemplate">
<ref bean="sqlSessionTemplate"/>
</property>
</bean>
- 自動掃描配置
<!-- 采用自動掃描方式創(chuàng)建mapper bean(單個更新模式) -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.xxx.dao" />
<property name="sqlSessionTemplateBeanName" value="sqlSessionTemplateSimple" />
<property name="markerInterface" value="com.xxx.dao.SimpleDao" />
</bean>
<!-- 采用自動掃描方式創(chuàng)建mapper bean(批量更新模式) -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.xxx.dao" />
<property name="sqlSessionTemplateBeanName" value="sqlSessionTemplateBatch" />
<property name="markerInterface" value="com.xxx.dao.BatchDao" />
</bean>
- mapperScannerConfigurer解析
- 實現(xiàn)BeanDefinitionRegistryPostProcessor接口塘雳，實現(xiàn)
MapperScannerConfigurer implements BeanDefinitionRegistryPostProcessor, InitializingBean, ApplicationContextAware, BeanNameAware
- 重寫postProcessBeanDefinitionRegistry方法 通過ClassPathMapperScanner掃描包
@Override
public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) {
if (this.processPropertyPlaceHolders) {
processPropertyPlaceHolders();
}
ClassPathMapperScanner scanner = new ClassPathMapperScanner(registry);
scanner.setAddToConfig(this.addToConfig);
scanner.setAnnotationClass(this.annotationClass);
scanner.setMarkerInterface(this.markerInterface);
scanner.setSqlSessionFactory(this.sqlSessionFactory);
scanner.setSqlSessionTemplate(this.sqlSessionTemplate);
scanner.setSqlSessionFactoryBeanName(this.sqlSessionFactoryBeanName);
scanner.setSqlSessionTemplateBeanName(this.sqlSessionTemplateBeanName);
scanner.setResourceLoader(this.applicationContext);
scanner.setBeanNameGenerator(this.nameGenerator);
//過濾 可以通過接口過濾 或者注解過濾
scanner.registerFilters();
scanner.scan(StringUtils.tokenizeToStringArray(this.basePackage, ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS));
}
@Override
public Set<BeanDefinitionHolder> doScan(String... basePackages) {
//掃描包败明，注冊beandefinition
Set<BeanDefinitionHolder> beanDefinitions = super.doScan(basePackages);
if (beanDefinitions.isEmpty()) {
logger.warn("No MyBatis mapper was found in '" + Arrays.toString(basePackages) + "' package. Please check your configuration.");
} else {
processBeanDefinitions(beanDefinitions);
}
return beanDefinitions;
}
private void processBeanDefinitions(Set<BeanDefinitionHolder> beanDefinitions) {
GenericBeanDefinition definition;
for (BeanDefinitionHolder holder : beanDefinitions) {
definition = (GenericBeanDefinition) holder.getBeanDefinition();
if (logger.isDebugEnabled()) {
logger.debug("Creating MapperFactoryBean with name '" + holder.getBeanName()
+ "' and '" + definition.getBeanClassName() + "' mapperInterface");
}
// MapperFactoryBean 實現(xiàn)factoryBean接口
definition.getPropertyValues().add("mapperInterface", definition.getBeanClassName());
//設(shè)置bean的class類型
definition.setBeanClass(this.mapperFactoryBean.getClass());
definition.getPropertyValues().add("addToConfig", this.addToConfig);
boolean explicitFactoryUsed = false;
if (StringUtils.hasText(this.sqlSessionFactoryBeanName)) {
definition.getPropertyValues().add("sqlSessionFactory", new RuntimeBeanReference(this.sqlSessionFactoryBeanName));
explicitFactoryUsed = true;
} else if (this.sqlSessionFactory != null) {
definition.getPropertyValues().add("sqlSessionFactory", this.sqlSessionFactory);
explicitFactoryUsed = true;
}
if (StringUtils.hasText(this.sqlSessionTemplateBeanName)) {
if (explicitFactoryUsed) {
logger.warn("Cannot use both: sqlSessionTemplate and sqlSessionFactory together. sqlSessionFactory is ignored.");
}
definition.getPropertyValues().add("sqlSessionTemplate", new RuntimeBeanReference(this.sqlSessionTemplateBeanName));
explicitFactoryUsed = true;
} else if (this.sqlSessionTemplate != null) {
if (explicitFactoryUsed) {
logger.warn("Cannot use both: sqlSessionTemplate and sqlSessionFactory together. sqlSessionFactory is ignored.");
}
definition.getPropertyValues().add("sqlSessionTemplate", this.sqlSessionTemplate);
explicitFactoryUsed = true;
}
if (!explicitFactoryUsed) {
if (logger.isDebugEnabled()) {
logger.debug("Enabling autowire by type for MapperFactoryBean with name '" + holder.getBeanName() + "'.");
}
definition.setAutowireMode(AbstractBeanDefinition.AUTOWIRE_BY_TYPE);
}
}
}
//通過spring調(diào)用此方法，注冊mapper實例
public T getObject() throws Exception {
return this.getSqlSession().getMapper(this.mapperInterface);
}
