jpa 多对多关系的实现注解形式
1, 表结构
1)设备表 VTM_DEVICE_INFO
create table VTM_DEVICE_INFO ( ID INTEGER not null, SN VARCHAR2(32) not null, STATUS INTEGER, MEMO VARCHAR2(256), DEVICE_NO INTEGER, START_TIME TIMESTAMP(6), END_TIME TIMESTAMP(6), FACTORY INTEGER, DEVICE_IN_DATE TIMESTAMP(6), ISAFEDOOR_POSITION INTEGER, AUDIT_FLAG VARCHAR2(1) ); alter table VTM_DEVICE_INFO add constraint PK_VTM_DEVICE_INFO primary key (ID);
2)模块表 VTM_MODULE_DEFINE
create table VTM_MODULE_DEFINE ( ID INTEGER not null, MODULE_NAME VARCHAR2(50) not null ); alter table VTM_MODULE_DEFINE add constraint PK_VTM_MODULE_DEFINE primary key (ID);
3)设备模块关系表 VTM_DEVICE_MODULE
create table VTM_DEVICE_MODULE ( DEVICE_ID INTEGER not null, MODULE_ID INTEGER not null ) ; alter table VTM_DEVICE_MODULE add constraint FK_VTM_DEVI_REF_DEVIC_VTM_DEVI foreign key (DEVICE_ID) references VTM_DEVICE_INFO (ID); alter table VTM_DEVICE_MODULE add constraint FK_VTM_DEVI_REF_DEVIC_VTM_MODU foreign key (MODULE_ID) references VTM_MODULE_DEFINE (ID);
4)初始化模块表数据
insert into VTM_MODULE_DEFINE (ID, MODULE_NAME) values (1, '读卡器'); insert into VTM_MODULE_DEFINE (ID, MODULE_NAME) values (2, '密码键盘'); insert into VTM_MODULE_DEFINE (ID, MODULE_NAME) values (3, '取款模块'); insert into VTM_MODULE_DEFINE (ID, MODULE_NAME) values (4, '存款模块');
5)数据库中要到的序列
create sequence DEVICE_INFO_SEQ minvalue 1 maxvalue 9999999999 start with 101 increment by 1 cache 20; create sequence DEVICE_MODULE_SEQ minvalue 1 maxvalue 9999999999 start with 1 increment by 1 cache 20;
设备表 与 模块表 之间是多对多的关系,关系表为 设备模块表
2,实体类采用注解的形式,体现他们之间的关系
package opstools.vtm.device.entity; import java.io.Serializable; import java.util.Date; import java.util.Set; import javax.persistence.CascadeType; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persistence.JoinColumn; import javax.persistence.JoinTable; import javax.persistence.ManyToMany; import javax.persistence.ManyToOne; import javax.persistence.SequenceGenerator; import javax.persistence.Table; import javax.persistence.Temporal; import javax.persistence.TemporalType;/** * 设备实体类 * @author yangw */ @Entity @Table(name = "VTM_DEVICE_INFO") @SequenceGenerator(name = "deviceInfoSeq", sequenceName = "DEVICE_INFO_SEQ") public class DeviceInfo implements Serializable { private static final long serialVersionUID = -6964820074623402896L; @Id @Column(name="ID") @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "deviceInfoSeq") private Integer deviceId; //设备Id @Column private String sn; //序号 @Column private Integer status; //设备使用状态 @Column private Integer branchId; @Column private String memo; //备注信息 @Column private Integer deviceNo; //设备型号 @Temporal(TemporalType.TIMESTAMP) @Column private Date startTime; //开始使用时间 @Temporal(TemporalType.TIMESTAMP) @Column private Date endTime; //设备终止时间 @Column private Integer factory; //设备厂商 @Temporal(TemporalType.TIMESTAMP) @Column private Date deviceInDate; //设备增加时间 @Column private Integer isafedoorPosition; //开门方向 @Column private Integer auditFlag; //审核标志 @ManyToMany(cascade=CascadeType.PERSIST) @JoinTable(name = "VTM_DEVICE_MODULE", joinColumns = {@JoinColumn(name = "deviceId")},inverseJoinColumns=@JoinColumn(name="MODULE_ID")) private Set<ModuleDefine> moduleDefine; //get set 省略 }
package opstools.vtm.device.entity; import java.io.Serializable; import java.util.Set; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persistence.JoinColumn; import javax.persistence.JoinTable; import javax.persistence.ManyToMany; import javax.persistence.SequenceGenerator; import javax.persistence.Table; /** * 设备模块表 * @author yangw */ @Entity @Table(name = "VTM_MODULE_DEFINE") @SequenceGenerator(name = "moduleDefineSeq", sequenceName = "MODULE_DEFINE_SEQ") public class ModuleDefine implements Serializable { private static final long serialVersionUID = 1L; @Id @Column(name="ID") @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "moduleDefineSeq") private Integer moduleId; //模块Id @Column private String moduleName; //模块名称 @ManyToMany(mappedBy = "moduleDefine") private Set<DeviceInfo> deviceInfo; //省略 get set 这个类可能不需要再写@ManyToMany来维护关系,因为这个表的数据是初始化好的,不需要修改, 具体没有测试. }
3, dao层的实现,就是将 设备添加到数据库
@Override public void createDeviceInfo(DeviceInfo deviceInfo) { super.create(deviceInfo); }
4,service层的实现,将模块信息设置到设备类的属性中.
@Override public void createDeviceInfo(DeviceInfo deviceInfo, Integer[] moduleIds) { if(moduleIds!=null){ Set<ModuleDefine> defineSet=deviceInfo.getModuleDefine(); if(defineSet==null){ defineSet=new HashSet<ModuleDefine>(); } for(int i=0;i<moduleIds.length;i++){ ModuleDefine define=new ModuleDefine(); define.setModuleId(moduleIds[i]); defineSet.add(define); } deviceInfo.setModuleDefine(defineSet); } deviceInfoDao.createDeviceInfo(deviceInfo); }
5,action层的简单实现
@Override public void submitPage(String pageName) throws Exception { deviceInfo.setStartTime(DateSupportUtils.str2second(startTime)); deviceInfo.setEndTime(DateSupportUtils.str2second(endTime)); if(pageName.equals(PAGE_CREATE)){ deviceInfo.setDeviceInDate(new Date()); deviceInfoService.createDeviceInfo(deviceInfo,moduleIds); } else if(pageName.equals(PAGE_UPDATE)){ deviceInfoService.updateDeviceInfo(deviceInfo); } }
6,界面jsp页面,简单给大家看看.
<%@ page language="java" pageEncoding="UTF-8"%> <%@ taglib prefix="s" uri="/struts-tags" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <title>${pageTitle}</title> <s:include value="../../../include/page.jsp"/> <style type="shett"></style> <script type="text/javascript" >
//这里的代码是级联获取下拉框数据,省略掉,可以参考上一篇处理json的代码</script> </head> <body onload="Page.init('${pageError}','${pageMessage}',${isSubmit})"> <div id="title">${pageTitle}</div> <s:form id="MYFORM" action="%{pageAction}" method="post" theme="simple"> <input type="hidden" value="0" name="deviceInfo.status"/> <input type="hidden" value="0" name="deviceInfo.auditFlag"/> <div id="content"> <table> //下面一种标签只列出来了一个 <tr> <th width="13%">开始使用时间:</th> <td width="35%"><div> <input name="startTime" value="<s:date name="deviceInfo.startTime" format="yyyy-MM-dd HH:mm:ss"/>" class="Wdate" onfocus="WdatePicker({isShowClear:false,dateFmt:'yyyy-MM-dd HH:mm:ss',readOnly:true})"/> </div></td> </tr> <tr> <th width="17%">设备厂商:</th> <td width="35%"><s:select name="deviceInfo.factory" id="deviceFactory" list="deviceFactoryList" listKey="realValue" listValue="displayValue" headerKey="" headerValue="请选择"/> </td> </tr> <tr> <th width="17%">模块:</th> <td width="35%" > <div> <s:checkboxlist name="moduleIds" cssClass="checkbox" list="moduleList" listKey="realValue" listValue="displayValue" > </s:checkboxlist> </div> </td> </tr> <tr> <th width="13%">备注信息:</th> <td width="35%" colspan="3" ><div> <s:textarea name="deviceInfo.memo" onblur="Check.checkLength(this,256)"/> </div></td> </tr> </table> </div> <div id="operator"> <div class="left"></div> <div class="middle" onclick="Page.submit()">提交</div> <div class="right"></div> <div class="left"></div> <div class="middle" onclick="Page.close()">关闭</div> <div class="right"></div> </div> </s:form> </body> </html>
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