hibernate操作大文本字段Blob和Clob

Posted 2020-09-19 panzer

hibernate操作大文本字段Blob和Clob解决方案：

1.大文本字段Blob和Clob(流);

2.截串存取

第一步： 创建新表：Elec_CommonMsg_Content

create table Elec_CommonMsg_Content(
    comID varchar(50) not null primary key comment \'主键ID\',
    type char(2) null comment \'判断站点运行和设备运行的标示\',
    content varchar(5000) null comment \'数据内容\',
    orderby int null comment \'数据显示排序\' 
)

 第二步：在elec.domain中创建ElecCommonMsgContent的javabean和映射文件

package com.elec.domain;

import java.io.Serializable;

@SuppressWarnings("serial")
public class ElecCommonMsgContent implements Serializable{

    private String comID;//主键ID
    private String type;//判断站点和设备运行的标示
    private String content;//数据内容
    private Integer orderby;//数据显示排序
    public String getComID() {
        return comID;
    }
    public void setComID(String comID) {
        this.comID = comID;
    }
    public String getType() {
        return type;
    }
    public void setType(String type) {
        this.type = type;
    }
    public String getContent() {
        return content;
    }
    public void setContent(String content) {
        this.content = content;
    }
    public Integer getOrderby() {
        return orderby;
    }
    public void setOrderby(Integer orderby) {
        this.orderby = orderby;
    }
    
    
    
}

 

 映射文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="com.elec.domain.ElecCommonMsgContent" table="elec_commonmsg_content">
        <id name="comID" type="string" column="comID">
                <generator class="uuid"></generator>            
        </id>
        <property name="type" type="string" column="type"></property>
        <property name="content" type="string" column="content"></property>
        <property name="orderby" type="integer" column="orderby"></property>
    </class>
</hibernate-mapping>

 

在hibernate中添加该映射文件：

    <!-- 添加映射 -->
        <mapping resource="com/elec/domain/ElecText.hbm.xml"/>
        <mapping resource="com/elec/domain/ElecCommonMsg.hbm.xml"/>
        <mapping resource="com/elec/domain/ElecCommonMsgContent.hbm.xml"/>

 

第三步：创建两个Dao

IElecCommonMsgContentDao.java

package com.elec.dao;

import com.elec.domain.ElecCommonMsgContent;

public interface IElecCommonMsgContentDao extends ICommonDao<ElecCommonMsgContent>{

    public static final String SERVICE_NAME = "com.elec.dao.impl.ElecCommonMsgContentDaoImpl";

}

 

ElecCommonMsgContentDaoImpl.java

package com.elec.dao.impl;

import org.springframework.stereotype.Repository;

import com.elec.dao.IElecCommonMsgContentDao;
import com.elec.dao.IElecCommonMsgDao;
import com.elec.domain.ElecCommonMsg;
import com.elec.domain.ElecCommonMsgContent;
/**
 * @Repository() == <bean id="" class="">
 * @author kj
 *
 */
@Repository(IElecCommonMsgContentDao.SERVICE_NAME)
public class ElecCommonMsgContentDaoImpl extends CommonDaoImpl<ElecCommonMsgContent> implements IElecCommonMsgContentDao{

}

 第四步：创建分割文本字符串的方法：StringUtil.java

 

package com.elec.web.utils;

import java.util.ArrayList;
import java.util.List;

public class StringUtil {
/**
 * 
 * @param wholecontent:传递文本字符串
 * @param count :需要分隔符的字符串的长度
 * @return 分割后的List集合，    存放结果集
 */
    public static List<String> getContentByList(String wholeContent, int cutCount){
        List<String> list = new ArrayList<>();
        //获取完整内容字符串的总长度
        int contentlen = wholeContent.length();
        //内容截取，用内容总长度和截取长度进行比较，无需截取的话就直接插入
        if(contentlen < cutCount){
            list.add(wholeContent);
        }else{
            //定义并初始化内容
            String contentPart = "";
            //定义并初始化被截取的段落数量
            int contentRound = 0;
            //开始位置
            int beginCount = 0;
            //判断截取的段落数
            int contentCutPart = contentlen/cutCount;
            int contentCutParts = contentlen%cutCount;//求余数
            //如果余数为零，说明被整除，内容的长度正好是截取长度的倍数
            if(contentCutParts == 0){
                contentRound = contentCutPart;
            }else{
                contentRound = contentCutPart + 1;
            }
            //循环截取内容
            for(int i = 1; i <= contentRound; i++){
                //如果不是最后一个截取内容
                if(i != contentRound){
                    //按照截断长度截取内容
                    contentPart = wholeContent.substring(beginCount, cutCount*i    );
                }else{
                    //截取最后一部分内容
                    contentPart =     wholeContent.substring(beginCount,contentlen);
                }
                //赋值下一个截取部分的起点位置
                beginCount = cutCount * i;
                list.add(contentPart);
            }
        }
        return list;
    }
}

 

第四步：修改对应的service文件：

ElecCommonMsgServiceImpl.java

 

package com.elec.service.impl;

import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import javax.annotation.Resource;

import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

import com.elec.dao.IElecCommonMsgContentDao;
import com.elec.dao.IElecCommonMsgDao;
import com.elec.domain.ElecCommonMsg;
import com.elec.domain.ElecCommonMsgContent;
import com.elec.service.IElecCommonMsgService;
import com.elec.web.utils.StringUtil;

/**
 * Service 
 *相当于在spring容器中定义：
 *<bean id > </bean>
 * @author kj
 *
 */
@Service(IElecCommonMsgService.SERVICE_NAME)
@Transactional(readOnly=true)
public class ElecCommonMsgServiceImpl implements IElecCommonMsgService {
//运行监控表Dao
    @Resource(name=IElecCommonMsgDao.SERVICE_NAME)
    IElecCommonMsgDao elecCommonMsgDao;
    //运行监控数据表Dao
    @Resource(name=IElecCommonMsgContentDao.SERVICE_NAME)
    IElecCommonMsgContentDao elecCommonMsgContentDao;
    
    
    @Override
    @Transactional(isolation=Isolation.DEFAULT,propagation=Propagation.REQUIRED,readOnly=false)
    public void saveElecCommonMsg(ElecCommonMsg elecCommonMsg) {
        List<ElecCommonMsgContent> contentList = elecCommonMsgContentDao.findCollectionByConditionNoPage("", null, null);
        elecCommonMsgContentDao.deleteObjectByCollection(contentList);
        //从页面获取站点运行情况
        String stationRun = elecCommonMsg.getStationRun();
        String devRun = elecCommonMsg.getDevRun();
        //调用StringUtil方法，分割字符串
        List<String>  stationList = StringUtil.getContentByList(stationRun, 50);
        if(stationList != null && stationList.size() > 0){
            for(int i=0;i<stationList.size();i++){
                ElecCommonMsgContent elecCommonMsgContent = new ElecCommonMsgContent();
                elecCommonMsgContent.setType("1");
                elecCommonMsgContent.setContent(stationList.get(i));
                elecCommonMsgContent.setOrderby(i + 1);
                elecCommonMsgContentDao.save(elecCommonMsgContent);
            }
        }
        List<String> devList = StringUtil.getContentByList(devRun, 50);
        if(devList != null && devList.size() > 0){
            for(int i = 0;i<devList.size();i++){
                ElecCommonMsgContent elecCommonMsgContent = new ElecCommonMsgContent();
                elecCommonMsgContent.setType("2");
                elecCommonMsgContent.setContent(devList.get(i));
                elecCommonMsgContent.setOrderby(i + 1);
                elecCommonMsgContentDao.save(elecCommonMsgContent);
            }
        }
    }
    @Override
    public void updateElecCommonMsg(ElecCommonMsg elecCommonMsg) {
        // TODO Auto-generated method stub
        
    }
    @Override
    public ElecCommonMsg findCommonMsg() {
        List<ElecCommonMsg> list = elecCommonMsgDao.findCollectionByConditionNoPage("", null, null);
        ElecCommonMsg commonMsg = null;
        if(list != null && list.size() > 0){
            commonMsg = list.get(0);
            //获取数据内容，以类型为条件，按照显示顺序升序排列，查询站点运行情况
            String stationCondition = " and o.type=? ";
            Object [] stationParams = {"1"};
            Map<String,String> stationOrderBy = new LinkedHashMap<String,String>();
            stationOrderBy.put("o.orderby", "asc");
            List<ElecCommonMsgContent> stationList = elecCommonMsgContentDao.findCollectionByConditionNoPage(stationCondition, stationParams, stationOrderBy);
            //获取返回的数据
            String stationContent = "";
            if(stationList != null && stationList.size() > 0){
                for(ElecCommonMsgContent elecCommonMsgContent:stationList){
                    String content = elecCommonMsgContent.getContent();
                    stationContent += content;
                }
            }
            //    将数据赋值给页面的属性
            commonMsg.setStationRun(stationContent);
            
            String devCondition = " and o.type=? ";
            Object [] devParams = {"2"};
            Map<String,String> devOrderBy = new LinkedHashMap<String,String>();
            stationOrderBy.put("o.orderby", "asc");
            List<ElecCommonMsgContent> devList = elecCommonMsgContentDao.findCollectionByConditionNoPage(devCondition, devParams, devOrderBy);
            //获取返回的数据
            String devContent = "";
            if(devList != null && devList.size() > 0){
                for(ElecCommonMsgContent elecCommonMsgContent:devList){
                    String content = elecCommonMsgContent.getContent();
                    devContent += content;
                }
            }
            //    将数据赋值给页面的属性
            commonMsg.setDevRun(devContent);
        }
        return commonMsg;
    }
}