Spring、iBatis配置

   在Spring 中集成iBatis的配置是很简单了，下面是一个简单的配置示例：

 

Spring 的配置文件

 

 

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:p="http://www.springframework.org/schema/p" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:aop="http://www.springframework.org/schema/aop" xmlns:jee="http://www.springframework.org/schema/jee"
	xmlns:task="http://www.springframework.org/schema/task"
	xsi:schemaLocation="
		http://www.springframework.org/schema/beans
		http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
		http://www.springframework.org/schema/context
		http://www.springframework.org/schema/context/spring-context-3.0.xsd
		http://www.springframework.org/schema/aop 
		http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
		http://www.springframework.org/schema/tx
		http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
		http://www.springframework.org/schema/jee 
		http://www.springframework.org/schema/jee/spring-jee-3.0.xsd
		http://www.springframework.org/schema/task  
        http://www.springframework.org/schema/task/spring-task-3.1.xsd  
		">
	<context:component-scan base-package="com.david.demo.common.*" />
	<context:property-placeholder location="classpath:META-INF/config.properties" />
	<!-- 定义数据源 -->
	<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
		destroy-method="close">
		<property name="driverClass" value="${jdbc.ams.driver}" />
		<property name="jdbcUrl" value="${jdbc.ams.url}" />
		<property name="user" value="${jdbc.ams.username}" />
		<property name="password" value="${jdbc.ams.password}" />
		<property name="initialPoolSize" value="${initialSize}" />
		<property name="minPoolSize" value="${minPoolSize}" />
		<property name="maxPoolSize" value="${maxActive}" />
		<property name="acquireIncrement" value="${acquireIncrement}" />
		<property name="maxIdleTime" value="${maxIdleTime}" />
	</bean>

	<bean id="sqlMapClient" class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">
		<property name="dataSource" ref="dataSource" />
		<property name="configLocation" value="classpath:META-INF/sqlmap/sqlmap.xml" />
	</bean>

</beans>

 config.properties

jdbc.ams.driver=com.mysql.jdbc.Driver
jdbc.ams.url=jdbc:mysql://localhost:3306/test
jdbc.ams.username=root
jdbc.ams.password=root
initialSize=3
minPoolSize=5
maxActive=100
acquireIncrement=3
maxIdleTime=10

 sqlMap.xml

<?xml version="1.0" encoding="UTF-8"?>  
<!DOCTYPE sqlMapConfig        
    PUBLIC "-//ibatis.apache.org//DTD SQL Map Config 2.0//EN"        
    "http://ibatis.apache.org/dtd/sql-map-config-2.dtd">
<sqlMapConfig>
<!-- 
		cacheModelsEnable  是否启用sqlMapClient上的缓存机制，　
		enhancementEnabled 是否省队POJO启用字节码增强，提升getter/setter效率  
		lazyLoadingEnabled 是否启用延迟加载机制
		errorTracingEnable 是否启用错误日志
		maxRequest 最大并发请求数(Statement 并发数)
		maxSession 最大Session数(SqlMapClient 并发数) maxTransaction=<maxSession=<maxRequest
		maxTransactions 最大并发事务
		useStatemnetNamespaces 是否启用命名空间
	
 -->
	<settings cacheModelsEnabled="false" enhancementEnabled="true"
		lazyLoadingEnabled="true" errorTracingEnabled="true" useStatementNamespaces="true" maxRequests="3000"
		maxSessions="3000" maxTransactions="3000" />
	<sqlMap resource="META-INF/sqlmap/sqlmap-Book.xml" />
</sqlMapConfig> 

 sqlmap-Book.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE sqlMap        
    PUBLIC "-//ibatis.apache.org//DTD SQL Map 2.0//EN"        
    "http://ibatis.apache.org/dtd/sql-map-2.dtd">
<sqlMap namespace="demo">

	<resultMap class="com.david.common.domain.Book" id="BooKMap">
		<result property="id" column="id" javaType="int" />
		<result property="name" column="name" javaType="java.lang.String" />
		<result property="price" column="price" javaType="int" nullValue="0" />
		<result property="extend" column="extend" typeHandler="com.david.demo.common.handler.ExtendTypeHandler"/>
	</resultMap>
	
	<typeAlias alias="Book" type="com.david.common.domain.Book" />
	<parameterMap class="Book" id="book">   
        <parameter property="name" javaType="java.lang.String" nullValue="test"/>
        <parameter property="price" javaType="int" nullValue="0"/>
        <parameter property="extend" typeHandler="com.david.demo.common.handler.ExtendTypeHandler" />  
    </parameterMap> 
	
	<insert id="insert" parameterMap="book">
		insert into t_book (name,price,extend) values (?,?,?)
		<selectKey keyProperty="id" resultClass="Integer">
			select
			LAST_INSERT_ID()
		</selectKey>
	</insert>
	<select id="select-all" resultMap="BooKMap">
		select id,name,price,extend,gmt_create,gmt_modify from t_book
	</select>

	<delete id="delete-by-id">
		delete from t_book where id=#id#
	</delete>

</sqlMap>

 

 iBatis执行SQL的关键入口是SqlMapClientImpl。通过该类的源码可以发现，在构造方法中注入了一个SqlMapExecutorDelegate 实例，但该类并不真正执行Sql 而是通过SqlMapSession去执行的。

/**
 * Implementation of ExtendedSqlMapClient
 */
public class SqlMapClientImpl implements SqlMapClient, ExtendedSqlMapClient {

  private static final Log log = LogFactory.getLog(SqlMapClientImpl.class);

  /**
   * 执行SQL的代理
   */
  public SqlMapExecutorDelegate delegate;

  protected ThreadLocal localSqlMapSession = new ThreadLocal();

  /**
   * Constructor to supply a delegate
   *
   * @param delegate - the delegate
   */
  public SqlMapClientImpl(SqlMapExecutorDelegate delegate) {
    this.delegate = delegate;
  }

  public Object insert(String id, Object param) throws SQLException {
    return getLocalSqlMapSession().insert(id, param);
  }

...
/**
	获取当前线程的SqlMapSession,如果当前线程中没有SqlMapSession或SqlMapSession已经关闭，则创建一个新的SqlMapSession 并存入到当前线程中。
*/
  protected SqlMapSessionImpl getLocalSqlMapSession() {
    SqlMapSessionImpl sqlMapSession = (SqlMapSessionImpl) localSqlMapSession.get();
    if (sqlMapSession == null || sqlMapSession.isClosed()) {
	 // 使用当前SqlMapClientImpl 作为构造参数构造一个新的SqlMapSession实例
      sqlMapSession = new SqlMapSessionImpl(this);
	  // 将实例放入ThreadLocal中
      localSqlMapSession.set(sqlMapSession);
    }
    return sqlMapSession;
  }
...
}

 通过SqlMapSessionImpl 的源码可以发现，在构造函数中，将SqlMapClientImpl中的属性delegate赋值给了SqlMapSessionImpl的属性delegate,同时可以发现SqlMapExecutorDelegate是真正执行Sql的地方

**
 * Implementation of SqlMapSession
 */
public class SqlMapSessionImpl implements SqlMapSession {

  protected SqlMapExecutorDelegate delegate;
  protected SessionScope sessionScope;
  protected boolean closed;

  /**
   * Constructor
   *
   * @param client - the client that will use the session
   */
  public SqlMapSessionImpl(SqlMapClientImpl client) {
    this.delegate = client.getDelegate();
    this.sessionScope = this.delegate.beginSessionScope();
    this.sessionScope.setSqlMapClient(client);
    this.sessionScope.setSqlMapExecutor(client);
    this.sessionScope.setSqlMapTxMgr(client);
    this.closed = false;
  }

  /**
   * Start the session
   */
  public void open() {
    sessionScope.setSqlMapTxMgr(this);
  }

  /**
   * Getter to tell if the session is still open
   *
   * @return - the status of the session
   */
  public boolean isClosed() {
    return closed;
  }

  public void close() {
    if (delegate != null && sessionScope != null) delegate.endSessionScope(sessionScope);
    if (sessionScope != null) sessionScope = null;
    if (delegate != null) delegate = null;
    if (!closed) closed = true;
  }
// 使用SqlMapExecutorDelegate去执行SQL
  public Object insert(String id, Object param) throws SQLException {
    return delegate.insert(sessionScope, id, param);
  }
  ...

 

评论

2 楼 zhangwei_david 2015-02-27  

x_root 写道

现在都用mybatis了哦。

我们项目还是在使用iBatis

1 楼 x_root 2015-02-27  

现在都用mybatis了哦。