MyBatis批量插入数据过程解析

public class TrainRecord implements Serializable { 
   private static final long serialVersionUID = -1206960462117924923L;  
  private long id;  
  private long activityId; 
  private long empId; 
  private int flag;  
  private String addTime;      
  //setter and getter   
} 

<resultMap type="TrainRecord" id="trainRecordResultMap"> 
  <id column="id" property="id" jdbcType="BIGINT" /> 
  <result column="add_time" property="addTime" jdbcType="VARCHAR" /> 
  <result column="emp_id" property="empId" jdbcType="BIGINT" /> 
  <result column="activity_id" property="activityId" jdbcType="BIGINT" /> 
  <result column="flag" property="status" jdbcType="VARCHAR" /> 
</resultMap> 

<insert id="addTrainRecordBatch" useGeneratedKeys="true" parameterType="java.util.List"> 
  <selectKey resultType="long" keyProperty="id" order="AFTER"> 
    SELECT 
    LAST_INSERT_ID() 
  </selectKey> 
  insert into t_train_record (add_time,emp_id,activity_id,flag)  
  values 
  <foreach collection="list" item="item" index="index" separator="," > 
    (#{item.addTime},#{item.empId},#{item.activityId},#{item.flag}) 
  </foreach> 
</insert> 

public class MySqlBaseDAO extends SqlSessionDaoSupport { 
  /** 
   * insert:插入操作. <br/> 
   * 
   * @author chenzhou 
   * @param method 插入操作的方法名 
   * @param entity 查询参数或实体类 
   * @return 返回影响的行数 
   * @since JDK 1.6 
   */ 
  public int insert(String method,Object entity){ 
    return this.getSqlSession().insert(method, entity); 
  }      
  //其余方法省略 
} 

public class TrainRecordDAO extends MySqlBaseDAO { 
  /** 
   * addTrainRecordBatch:批量插入培训记录. <br/> 
   * 
   * @author chenzhou 
   * @param trainRecordList 培训记录list集合 
   * @return 影响的行数 
   * @since JDK 1.6 
   */ 
  public int addTrainRecordBatch(List<TrainRecord> trainRecordList){ 
    return this.insert("addTrainRecordBatch", trainRecordList); 
  }    
  //省略其余的方法 
} 

<![CDATA[ 
  select * from t_train_record t where t.activity_id=#{activityId} 
]]> 

<![CDATA[ 
  insert into t_train_record (add_time,emp_id,activity_id,flag) 
  values 
  <foreach collection="list" item="item" index="index" separator="," > 
    (#{item.addTime},#{item.empId},#{item.activityId},#{item.flag}) 
  </foreach> 
]]>