ibatis 动态查询

http://www.iteye.com/topic/393042最近做了很多动态的查询,尤其是排序,以及一些状态字段,所以就做了一个总的动态查询,以不变应万变,呵呵

ibatis 里面的sql代码:

Xml代码
        <select id="getTopics" resultClass="topic" parameterClass="map">
                        <![CDATA[
                                select * from p_Topic
                        ]]>
                <dynamic prepend=" WHERE ">
                        <isPropertyAvailable property="authorId">
                                <isNotNull property="authorId" prepend=" and ">
                                        authorId=#authorId#
                </isNotNull>
                        </isPropertyAvailable>
                        <isPropertyAvailable property="marketId">
                                <isNotNull property="marketId" prepend=" and ">
                                        marketId=#marketId#
                </isNotNull>
                        </isPropertyAvailable>

                        <isPropertyAvailable property="isDelete">
                                <isNotNull property="isDelete" prepend=" and ">
                                        isDelete=#isDelete#
                </isNotNull>
                        </isPropertyAvailable>

                        <isPropertyAvailable property="isBest">
                                <isNotNull property="isBest" prepend=" and ">
                                        isBest=#isBest#
                                </isNotNull>
                        </isPropertyAvailable>

                        <isPropertyAvailable property="statusStr">
                                <isNotNull property="statusStr" prepend=" and ">
                                        $statusStr$
                                </isNotNull>
                        </isPropertyAvailable>
                        <isPropertyAvailable property="marketIdList">
                                <isNotNull property="marketIdList" prepend=" and marketId in ">
                                        <iterate property="marketIdList" conjunction="," close=")" open="(">
                                                #marketIdList[]#
                                        </iterate>
                                </isNotNull>
                        </isPropertyAvailable>
                </dynamic>

                <dynamic prepend=" order by ">
                        <isPropertyAvailable property="orderStr">
                                <isNotNull property="orderStr">
                                        $orderStr$
                </isNotNull>
                        </isPropertyAvailable>
                </dynamic>

                <dynamic>
                        <isPropertyAvailable property="begin">
                                <isNotNull property="begin">
                                        limit #begin#
                </isNotNull>
                        </isPropertyAvailable>
                        <isPropertyAvailable property="max" prepend=" , ">
                                <isNotNull property="max">
                                        #max#
                </isNotNull>
                        </isPropertyAvailable>
                </dynamic>
        </select>



        <select id="getTopicCount" resultClass="java.lang.Long"
                parameterClass="map">
                        <![CDATA[
                                select count(id) from p_Topic
                        ]]>
                <dynamic prepend=" WHERE ">
                        <isPropertyAvailable property="authorId">
                                <isNotNull property="authorId" prepend=" and ">
                                        authorId=#authorId#
                </isNotNull>
                        </isPropertyAvailable>
                        <isPropertyAvailable property="marketId">
                                <isNotNull property="marketId" prepend=" and ">
                                        marketId=#marketId#
                </isNotNull>
                        </isPropertyAvailable>

                        <isPropertyAvailable property="isDelete">
                                <isNotNull property="isDelete" prepend=" and ">
                                        isDelete=#isDelete#
                </isNotNull>
                        </isPropertyAvailable>

                        <isPropertyAvailable property="isBest">
                                <isNotNull property="isBest" prepend=" and ">
                                        isBest=#isBest#
                                </isNotNull>
                        </isPropertyAvailable>

                        <isPropertyAvailable property="statusStr">
                                <isNotNull property="statusStr" prepend=" and ">
                                        $statusStr$
                                </isNotNull>
                        </isPropertyAvailable>
                        <isPropertyAvailable property="marketIdList">
                                <isNotNull property="marketIdList" prepend=" and ">
                                        <iterate property="marketIdList" conjunction="," close=")" open=" marketId in (">
 
                                                #marketIdList[]#
                                        </iterate>
                                </isNotNull>
                        </isPropertyAvailable>
                </dynamic>
        </select>

这里需要注意的是:

①#xxx#  代表xxx是属性值,map里面的key或者是你的pojo对象里面的属性,ibatis会自动在它的外面加上引号,表现在sql语句是这样的 where xxx = 'xxx' ;

   而$xxxx$ 则是把xxxx作为字符串拼接到你的sql语句中,比如 order by  topicId , 如果你不用$来拼接而用#的话,外面就会被加上引号的哦    比如你的语句这样写  ... order by #xxx# (xxx就是你传进来的字符串topicId),ibatis 就会把他翻译成  order by 'topicId' 这样就报错了 ,用$的结果就是这样  order by topicId

②这里的iterate

Java代码
 
         <isPropertyAvailable property="marketIdList">  
            <isNotNull property="marketIdList" prepend="and">  
                <iterate property="marketIdList" conjunction="," open=" marketId in (" close=")">  
                    #marketIdList[]#  
                </iterate>  
            </isNotNull>  
        </isPropertyAvailable>
 
 
注意 iterate 的property属性 ,虽然你上面的isNotNull什么的都有这句,但这里一定要写清楚,否则ibatis会找不到你的list的
 
数据访问层代码:
 
Java代码
               public List<Topic> getTopics(Map<String, Object> map) {

                return getSqlMapClientTemplate().queryForList("getTopics", map);
        }
 
 
 服务层代码:
 
Java代码
        public List<Topic> getTopicsByMarketIdList(Long authorId,List<Long> marketIdList,
                        Integer orderby, Integer status, Pagination pagination) {
                Map<String, Object> map = new HashMap<String, Object>();
                map.put("authorId", authorId);
                map.put("isDelete", false);
                map.put("marketIdList", marketIdList);
                map.put("orderStr", "这里你组装你的order字符串");
                map.put("statusStr","这里你组装你的status字符串");
                map.put("begin", pagination.getOffset());
                map.put("max", pagination.getPageSize());
               //这个getTopicCount()方法和getTopics()大体是一致的,所以我的dao里面省略了它
                Long total = topicDao.getTopicCount(map);
                if (total == 0) {
                        return new ArrayList<Topic>();
                } else {
                        pagination.setTotal(total);
                        List<Topic> res = topicDao.getTopics(map);
                        return res;
                }
        }
 
Java代码
 
public class Topic extends BaseObject implements Serializable {
        /**
         *
         */
        private static final long serialVersionUID = -851973667810710701L;

        private Long id;
        private Long authorId;
        private String authorName;
        private Long marketId;
        private String title;
        private String tags;
        private String content;
        private Date pubdate;
        private Integer isBest;
        private Integer status;
        private Integer isDelete;
        private Integer clickCount;
        private Integer replyCount;
        private Date lastReplyTime;
       //getter and setter 省略...
}
 
Pagination代码:
 
Java代码
public class Pagination {

        /**
         * 要查看的页码
         */
        private int page;

        /**
         * 每页显示数
         */
        private int pageSize;

        /**
         * 一共有多少页
         */
        private int totalPage;

        /**
         * 一共有多少条记录
         */
        private long total;

        /**
         * 当前页的记录数
         */
        private int size;

        /**
         * 只需要topxx,不需要页数信息了
         */
        private boolean topOnly;

      /**
       *从第几条记录开始        
       */
        private int offset;
        
        public void setOffset(int offset) {
                this.offset = offset;
        }

        public Pagination(int page, int pageSize) {
                this.page = page;
                this.pageSize = pageSize;
        }

        public Pagination() {
        }

        public boolean require() {
                return pageSize > 0 ? true : false;
        }

        public int from() {
                return page * pageSize;
        }

        public int to() {
                return from() + size;
        }

        public int getPage() {
                return page;
        }

        public void setPage(int page) {
                this.page = page;
        }

        public int getPageSize() {
                return pageSize;
        }

        public void setPageSize(int pageSize) {
                this.pageSize = pageSize;
        }

        public int getTotalPage() {
                return totalPage;
        }

        public void setTotalPage(int totalPage) {
                this.totalPage = totalPage;
        }

        public long getTotal() {
                return total;
        }

        public void setTotal(long total) {
                this.total = total;
                if (pageSize > 0) {
                        this.totalPage = (int) Math.ceil(total / (double) pageSize);
                } else {
                        this.totalPage = 1;
                }
                if (page >= totalPage) {
                        page = totalPage - 1;
                }
                if (page < 0)
                        page = 0;
                if (pageSize > 0) {
                        if (page < totalPage - 1)
                                this.size = pageSize;
                        else
                                this.size = (int) (total % pageSize);
                } else {
                        this.size = (int) total;
                }
                offset=page * pageSize;
        }

        public int getOffset() {
                return offset;
        }

        public int getSize() {
                return size;
        }

        public void setSize(int size) {
                this.size = size;
        }

        public boolean isTopOnly() {
                return topOnly;
        }

        public void setTopOnly(boolean topOnly) {
                this.topOnly = topOnly;
        }

}
原文地址:https://www.cnblogs.com/svennee/p/4078812.html